Method and apparatus for massive random access and enhanced coverage in a wireless network

Abstract

This invention describes a method and apparatus for massive random access with enhanced coverage comprising: - a transceiver, - a processor, and - a memory storing instructions which, when executed, cause the apparatus to - determine a first configuration or first random-access codebook, wherein the first random-access codebook comprises M codewords of length T, wherein a codeword is used by the apparatus to transmit one or more second message, - determine a first codeword from the first random-access codebook; and - transmit one or more second messages according to the first codeword.

Description

[0001] 2025PF00195

[0002] 1 23.03.2026

[0003] METHOD AND APPARATUS FOR MASSIVE RANDOM ACCESS AND ENHANCED COVERAGE IN A WIRELESS NETWORK

[0004] FIELD OF THE INVENTION

[0005] This invention relates to a method, apparatus, and system for operating a wireless device such as a user equipment to enable massive random access enhance coverage in a wireless system such as a cellular system, a Wi-Fi network or the like.

[0006] BACKGROUND OF THE INVENTION

[0007] In conventional cellular networks, a primary station serves a plurality of secondary stations located within a cell served by this primary station. Wireless communication from the primary station towards each secondary station is done on downlink channels. Conversely, wireless communication from each secondary towards the primary station is done on uplink channels. The wireless communication can include data traffic (sometimes referred to User Data), and control information (also referred sometimes as signalling). This control information typically comprises information to assist the primary station and / or the secondary station to exchange data traffic (e.g. resource allocation / requests, physical transmission parameters, information on the state of the respective stations).

[0008] In the context of cellular networks as standardized by 3GPP, the primary station is referred to a base station, or a gNodeB (or gNB) in 5G (NR) or an eNodeB (or eNB) in 4G (LTE). The eNB / gNB is part of the Radio Access Network RAN, which interfaces to functions in the Core Network (CN). In the same context, the secondary station corresponds to a mobile station, or a User Equipment (or a UE) in 4G / 5G, which is a wireless client device or a specific role played by such device. The term “node” is also used to denote either a UE or a gNB / eNB.

[0009] Additionally, for example, in the case of PC5 interface or Sidelink communication, it is possible to have Direct communication between secondary stations, here UEs. It is then also possible for UEs to operate as Relays to allow for example out of coverage UEs to get an inter-mediate (or indirect) connection to the eNB or gNB. To be able to work as a relay, a UE may use discovery messages to establish new connections with other UEs.

[0010] Current wireless systems have increased requirements in reliability and coverage. For instance, to enable resilient communication in non-terrestrial networks or ensure that low power devices are capable of exchanging data. Furthermore, the number of wireless devices that may attempt to gain access to the network may increase in future wireless networks, thus, solutions for massive access are required.2025PF00195

[0011] 2 23.03.2026

[0012] SUMMARY OF THE INVENTION

[0013] An aim of the invention is to address above requirements and achieve increased coverage, reliability, and massive access by transmitting and receiving one or more repetitive signals in one or more beams.

[0014] To this end, it is proposed methods, and apparatuses, and computer program as defined in the appended claims.

[0015] The invention proposes the use of a codebook to determine codewords that can facilitate both massive random access and coverage enhancements, e.g., when transmitting uplink data. Massive random access is facilitated by (1) increasing the chances at least one of the transmissions (of a second message, e.g., preamble) can go through and (2) supporting the usage of several second messages, e.g., one or more preambles and / or a longer preamble. Coverage is enhanced by (3) using codewords that facilitate repetition and / or multiple transmission of second messages, e.g., preambles and / or parts of a long of a preamble and / or uplink data. A key feature of the invention is that the codewords that may represent transmission opportunities may share some common transmission opportunities. When codewords selected by wireless devices do not overlap (e.g. because there are only a few wireless devices), the coverage enhancement effect is stronger. When codewords selected by wireless devices do overlap (e.g. because there are many wireless devices), coverage enhancement because the proposed constructions ensure that codewords have at least a minimum of non-overlapping transmission occasions. Finally, the usage of a codebook to identify the codewords facilitates determining which transmission occasions are used by a wireless device, improving massive access.

[0016] To this end, it is proposed in a first aspect of the invention, a method for massive random access with enhanced coverage, comprising:

[0017] - determining, by a wireless device, a first codeword, wherein the first codeword is one entry of a first random-access codebook; wherein each entry of the first random-access codebook is a codeword to be used by a wireless device to transmit one or more second messages,

[0018] - transmitting, by the wireless device, one or more second message according to the first codeword.

[0019] In accordance with a second aspect of the invention, it is proposed an apparatus for massive random access with enhanced coverage comprising:

[0020] - a transceiver,

[0021] - a processor, and

[0022] - a memory storing instructions which, when executed, cause the apparatus to

[0023] - determining a first codeword, wherein the first codeword is one entry of a first randomaccess codebook; wherein each entry of the first random-access codebook is a codeword to be used by a wireless device to transmit one or more second messages,

[0024] - transmitting one or more second message according to the first codeword.

[0025] In a variant of the first and second aspects, the method comprises2025PF00195

[0026] 3 23.03.2026

[0027] determining, by the wireless device, the first random-access codebook. Optionally, the determining the first random-access codebook comprises the wireless device receiving an indication of the first codebook in a first configuration.

[0028] In another variant, the first codeword identifies N transmit occasions out of T possible transmit occasions. Optionally, at least two codewords share a common transmit occasion.

[0029] In another option, the first codeword shares a common transmit occasion with another codeword.

[0030] In another variant, the first codeword has Hamming weight N.

[0031] Furthermore, at least two codewords of Hamming weight N may have Hamming distance k = N-l.

[0032] In another option, the first codeword and another codeword have Hamming weight N, and the first codeword and the another codeword have Hamming distance K=N-1.

[0033] In another variant, any two sequences of transmit occasions from the first random-access codebook have at least K non-overlapping transmit occasions.

[0034] In another variant, the Hamming distance between any two distinct codewords in the first random-access codebook is at least K.

[0035] In another variant, the method further comprises:

[0036] - receiving, by the wireless device, a first message including an indication of N and / or T and / or K from a first access device; and

[0037] - using, by the wireless device, the indication to determine the first random-access codebook.

[0038] In a variant, the method further comprises:

[0039] - receiving, by the wireless device, a fourth message from a second access device, - determining, by the wireless device, one or more features of the fourth message, and - determining, by the wireless device, the first random-access codebook and / or the first codeword based on the one or more features of the fourth message.

[0040] Optionally, the one or more features comprise at least one of:

[0041] - the signal strength of the fourth message;

[0042] - the signal quality of the fourth message;

[0043] - the type of second access device;

[0044] - the number of wireless devices attempting to perform random -access. Optionally, a higher N value is selected when the signal strength is below a first threshold, and / or the signal quality is below a second threshold, and / or the distance to the second access device is greater than a third threshold. Alternatively or in combination a higher K value is selected when the signal strength is below a fourth threshold, and / or the signal quality is below a fifth threshold, and / or the distance to the second access device is greater than a sixth threshold.2025PF00195

[0045] 4 23.03.2026

[0046] In a variant, the two or more codewords or sequences of transmit occasions in the first random -access codebook form a Latin rectangle.

[0047] In another variant, the first random-access codebook is received from a third access device and / or a core network function.

[0048] In another variant, the first random-access codebook is determined from a pre-configured list or set of codebooks and the determined first random-access codebook is identified by means of a codebook index.

[0049] In another variant, the T transmission occasions are one of or a combination of:

[0050] - distinct time slots;

[0051] - distinct non-overlapping frequency sub-bands;

[0052] - distinct non-overlapping frequency sub-bands in a single equal timeslot;

[0053] - distinct non-overlapping blocks in the time-frequency plane;

[0054] - distinct transmit occasions in different beams;

[0055] - distinct transmit occasions associated to different geographical locations.

[0056] In another variant, the first random-access codebook is a binary constant weight code with word length T, code weight N and minimum Hamming distance K.

[0057] Optionally, the codebook is encoded by indicating the non-zero positions of the codewords.

[0058] In another variant, M distinct codewords form an TxM matrix comprising an MxM submatrix in which each row and each column contains exactly one '1'.

[0059] In another variant,

[0060] - the first random-access codebook comprises codewords of a first length N and a second length N2; or

[0061] - the first random-access codebook comprises codewords of a first length N and a second random-access codebook comprises codewords of a second length N2

[0062] and wherein

[0063] the codeword selection length and / or the codebook selection depends on a determined required codeword Hamming weight and / or length.

[0064] In another variant, the determined first random-access codebook and / or the selected first codeword depend on one or more of:

[0065] the device capabilities of the wireless device;

[0066] the detection of a second wireless device by the wireless device;

[0067] the detection of a transmission by a second wireless device when transmitting the second message.

[0068] In still another variant, the method further comprises:

[0069] - receiving, by the wireless device, a first message from a fourth access device, wherein the first message indicates a transmission chance;2025PF00195

[0070] 5 23.03.2026

[0071] and wherein transmitting, by the wireless device, the second message according to the first codeword comprises determining whether the wireless device can perform the transmission in a first set of communication resources or a second set of communication resources based on the indicated transmission chance.

[0072] In another variant, the method comprises:

[0073] - receiving, by the wireless device, a third message,

[0074] - wherein the communication resources and / or parameters used to transmit the third message are determined based on one or more of:

[0075] - the first codeword,

[0076] - the codebook entry of the selected first codeword,

[0077] - any transmission occasion indicated by the first codeword; or

[0078] - one or more transmitted second messages.

[0079] Moreover, the method may include

[0080] - transmit occasions are partitioned into two disjoint subsets A and B, and - codewords are pairs (a,b) with a in A and b in B.

[0081] In a variant, the first random-access codebook is generated by means of a codebook function characterized by one or more of the following features:

[0082] - the codebook function computes the first codeword by taking as input the index identifying the selected first codeword;

[0083] - the codebook function computes the first codeword as a linear combination of code basis vectors;

[0084] - the codebook function takes as input the desired Hamming distance between the first codeword and any other codeword; and

[0085] - the codebook function takes as input the desired Hamming weight of the codeword. In another variant, the first access device, the second access device, the third access device, and the fourth access device are the same, two, three or fourth different access devices.

[0086] Optionally, the one or more second messages transmitted according to the first codeword comprises 1, 2, 3,..., N different second messages, and wherein the combination of the 1, 2, 3,..., N second messages and / or codeword serve as identifier of the wireless device attempting to gain network access.

[0087] In another option, each second message transmitted in each transmission occasion encodes the first codeword identifier, and / or the identities of the one or more second messages, and / or a transformation to obtain the one or more second messages.

[0088] In another option, the first codeword determines the transmit occassions used in the transmission of the one or more messages and the parameters of the one or more second messages.

[0089] In another option, a second message comprises a wireless sensing signal, and the first codeword determines the transmit occasions used in the transmission of the one or more messages and the parameters of the one or more second messages2025PF00195

[0090] 6 23.03.2026

[0091] In another option, the N second messages transmitted in the T transmit occasions define an uplink preamble or uplink wake-up signal or uplink sounding reference signal.

[0092] In accordance with a third aspect of the invention it is proposed a method for massive random access with enhanced coverage comprising:

[0093] - transmitting, by an access device, a first message to one or more wireless devices, wherein the first message is used by the one or more wireless devices to determine a first random-access codebook and / or codeword for the transmission of one or more second messages; and

[0094] - receiving, by the access device, one or more second messages according to a first codeword from at least a first wireless device, and the access device determining the codeword and / or the one or more second messages transmitted according to the codeword.

[0095] In a fourth aspect of the invention, it is proposed an apparatus for massive random access with enhanced coverage comprising:

[0096] - a transceiver,

[0097] - a processor, and

[0098] - a memory storing instructions which, when executed, cause the apparatus to

[0099] - transmit a first message to one or more wireless devices, wherein the first message is used by the one or more wireless devices to determine a first random-access codebook and / or codeword for the transmission of one or more second messages; and

[0100] - receive one or more second messages according to a first codeword from at least a first wireless device, and

[0101] - determine the codeword and / or the one or more second messages transmitted according to the codeword.

[0102] In a fifth aspect of the invention, it is proposed a computer program for massive random access with enhanced coverage comprising computer instructions to perform the steps in the methods of first or third aspects of the invention.

[0103] It shall be understood that a preferred embodiment of the invention can also be any combination of the dependent claims or above embodiments with the respective independent claim.

[0104] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

[0105] BRIEF DESCRIPTION OF THE DRAWINGS

[0106] In the following drawings:

[0107] Fig. 1 schematically represents the overall cellular system including UEs, RAN, and core network;

[0108] Fig. 2 provides a schematic representation of a UE and its components; and Fig. 3 schematically represents different entities involved in a non-terrestrial network; Fig. 4 schematically represents a random-access procedure in a wireless network;2025PF00195

[0109] 7 23.03.2026

[0110] Fig. 5 schematically represents a signalling procedure by an access device;

[0111] Fig. 6 schematically represents the periodic transmission of SSB bursts;

[0112] Fig. 7 schematically represents examples of wireless devices according to some embodiments;

[0113] Fig. 8 schematically represents the distribution of a signal in a multitude of sets of communication resources according to embodiments of the invention;

[0114] Fig. 9 schematically represents the distribution of a first signal and a second signal in a multitude of sets of communication resources according to embodiments of the invention;

[0115] Fig. 10 schematically represents the distribution of a signal in a multitude of sets of communication resources and using several communication beams according to embodiments of the invention;

[0116] Fig. 11 schematically represents the distribution of a wireless sensing signal in a multitude of sets of communication resources according to embodiments of the invention;

[0117] Fig. 12 schematically represents the first, second, third, and fourth sets of communication resources as used in different embodiments of the invention;

[0118] Fig. 13 schematically represents a configuration, signal monitoring, and measurement reporting procedure according to some embodiments of the invention;

[0119] Fig. 14 schematically represents a message flow according to some embodiments of the invention;

[0120] Fig. 15 schematically represents the distribution of signals through several beams;

[0121] Fig. 16 schematically represents the distribution of a signal in a multitude of sets of communication resources and using several communication beams according to embodiments of the invention;

[0122] Fig. 17 schematically represents the selection of beams for the distribution of a signal through several beams based on the moving direction of the wireless device;

[0123] Fig. 18 schematically represents the selection of beams for the distribution of a signal according to embodiments of the invention;

[0124] Fig. 19 is a block diagram illustrating an example processor;

[0125] Fig. 20 schematically illustrates a communication procedure according to different embodiments of the invention;

[0126] Fig. 21 schematically illustrates a procedure in which the one or more second messages transmitted according to codeword are based on a wireless sensing signa; and

[0127] Fig. 22 schematically illustrates the transmitted second messages (wireless sensing signals) according to a codeword according to embodiments of the invention.2025PF00195

[0128] 8 23.03.2026

[0129] DETAILED DESCRIPTION OF EMBODIMENTS

[0130] Embodiments of the present invention are now described based on a cellular communication network environment, such as 5G or 6G. However, the present invention may also be used in connection with other wireless technologies.

[0131] Throughout the present disclosure, the abbreviation “gNB” (5G terminology) or “BS” (base station) or the term “access device” is intended to mean a wireless access device such as a cellular base station or a Wi-Fi access point or a ultrawide band (UWB) personal area network (PAN) coordinator. The gNB may consist of a centralized control plane unit (gNB-CU-CP), multiple centralized user plane units (gNB-CU-UPs) and / or multiple distributed units (gNB-DUs). The gNB is part of a radio access network (RAN), which provides an interface to functions in the core network (CN). The RAN is part of a wireless communication network. It implements a radio access technology (RAT). Conceptually, it resides between a communication device such as a mobile phone, a computer, or any remotely controlled machine and provides connection with its CN. The CN is the communication network’s core part, which offers numerous services to customers who are interconnected via the RAN. More specifically, it directs communication streams over the communication network and possibly other networks.

[0132] Furthermore, the terms “base station” (BS) and “network” may be used as synonyms in this disclosure. This means for example that when it is written that the “network” performs a certain operation it may be performed by a CN function of a wireless communication network, or by one or more base stations that are part of such a wireless communication network, and vice versa. It can also mean that part of the functionality is performed by a CN function of the wireless communication network and part of the functionality by the base station.

[0133] It is further noted that throughout the present disclosure only those blocks, components and / or devices that are relevant are shown in the accompanying drawings. Other blocks have been omitted for reasons of brevity. Furthermore, blocks designated by same reference numbers are intended to have the same or at least a similar function, so that their function is not described again later.

[0134] A cellular system is a wireless communication system that consists of three main components: user equipment (UE), radio access network (RAN), and core network (CN). These components work together to provide voice and data services to mobile users over a large geographic area.

[0135] In conventional cellular networks, a primary station serves a plurality of secondary stations located within a cell served by this primary station. Wireless communication from the primary station towards each secondary station is done on downlink channels. Conversely, wireless communication from each secondary towards the primary station is done on uplink channels. The wireless communication can include data traffic (sometimes referred to User Data), and control information (also referred sometimes as signalling). This control information typically comprises information to assist the primary station and / or the secondary station to exchange data traffic (e.g. resource allocation / requests,2025PF00195

[0136] 9 23.03.2026

[0137] physical transmission parameters, information on the state of the respective stations). In the context of cellular networks as standardized by 3GPP, the primary station is referred to a base station, or a gNodeB (or gNB) in 5G (NR) or an eNodeB (or eNB) in 4G (LTE). The eNB / gNB is part of the Radio Access Network RAN, which interfaces to functions in the Core Network (CN). In the same context, the secondary station corresponds to a mobile station, or a User Equipment (or a UE) in 4G / 5G, which is a wireless client device or a specific role played by such device. The term “node” is also used to denote either a UE or a gNB / eNB.

[0138] Additionally, for example, in the case of PC5 interface or Sidelink communication, it is possible to have Direct communication between secondary stations, here UEs. It is then also possible for UEs to operate as Relays to allow for example out of coverage UEs to get an inter-mediate (or indirect) connection to the eNB or gNB. To be able to work as a relay, a UE may use discovery messages to establish new connections with other UEs. Certain UEs may communicate with each other by using device-to-device communication, also known as sidelink communication using the PC5 interface that may rely on physical sidelink (PS) broadcast channel, PS shared channel, PS control, etc. Furthermore, the role of a relay node has been introduced in 3GPP. This relay node is a wireless communication station that includes functionalities for relaying communication between a primary station, e.g. a gNB and a secondary station, e.g. a UE. This relay function for example allows to extend the coverage of a cell to an out-of-coverage (OoC) secondary station. This relay node may be a mobile station or could be a different type of device. In the specifications for 4G, the Proximity Services (ProSe) functions are defined inter aha in TS 23.303, and TS 24.334 to enable - amongst others -connectivity for the cellular User Equipment (UE) that is temporarily not in coverage of the cellular network base station (eNB) serving the cell. This particular function is called ProSe UE-to-network relay, or Relay UE for short. The Relay UE relays application and network traffic in two directions between the OoC UE and the eNB. The local communication between the Relay UE and the OoC UE is called device-to-device (D2D) communication or Sidelink (also known as PC5) communication in TS 23.303 and TS 24.334. Once the relaying relation is established, the OoC-UE is, e.g., IP -connected via the Relay UE and acts in a role of “Remote UE”. This situation means the Remote UE has an indirect network connection to selected functions of the Core Network as opposed to a direct network connection to all Core Network functions that is the normal case. Furthermore, it has been introduced the role of a UE-to-UE relay node, i.e., a relay node re-laying the communication between two UE devices. The relay node relays the communications between UE devices. UEs may connect to the core network through a base station when in-coverage. In such relay scenarios, the relay devices may receive and store some information for some time before forwarding it towards the target device. This information that may be stored and forwarded may be discovery messages received from a source UE whereby the relay UE may release them at some point of time later. This information that may be stored and forwarded may be a SIB that may contain a timestamp.2025PF00195

[0139] 10 23.03.2026

[0140] User equipment (UE) is the device that a user uses to access the cellular system, such as a smartphone, a tablet, a laptop, loT device, or a wearable device. A UE typically may contain the following components:

[0141] - A universal integrated circuit card (UICC), which stores the user's identification and authentication information, such as the subscription permanent identifier (SUPI) or credentials.

[0142] - A transceiver, which converts the digital signals from the processor into analog signals for transmission and reception over the air interface. The transceiver also performs modulation, demodulation, coding, decoding, and other signal processing functions.

[0143] - A processor, which controls the operation of the UE and executes the applications and services that the user requests. The processor also communicates with the RAN and the CN using various protocols.

[0144] - A display, which shows the user the information and feedback from the UE, such as the signal strength, the battery level, the call status, the messages, the contacts, the menu, etc.

[0145] - A microphone and a speaker, which enable the user to make and receive voice calls, as well as use other audio features, such as voice mail, voice recognition, etc.

[0146] - A keyboard and / or a touch screen, which allow the user to enter and select commands, text, numbers, etc.

[0147] - A camera and / or a video recorder, which enable the user to capture and send images and videos, as well as use other multimedia features, such as video calling, video streaming, etc.

[0148] - A memory, which stores the data and programs that the user needs, such as the phone book, the messages, the photos, the videos, the applications, etc as well as a computer program to perform the operations of the RAN and CN protocols.

[0149] - A battery, which provides the power supply for the UE.

[0150] Fig. 2 provides a schematic representation of a UE and its components, e.g., UICC (201), processor (202), transceiver (203), memory (204), input devices (205) such as camera, microphone, etc and output devices (206) such as display, speaker, etc. Fig. 7 schematically represents wireless devices that may include the capabilities of a UE and / or a STA. Fig. 7a) represents AR / VR glasses; Fig. 7b) represents a connected vehicle; and Fig. 7c) represents a mobile phone. In these devices, a reflective intelligent surface (RIS) may be embedded, e.g., by covering and / or under the whole a part of the UE surface. This may be used, e.g., to better deal with interferences or improve wireless sensing.

[0151] A UE may access the cellular network via the radio access network, as described below. Certain UEs may communicate with each other by using device-to-device communication, also known as sidelink communication using the PC5 interface that may rely on physical sidelink (PS) broadcast channel, PS shared channel, PS control channel, etc.

[0152] A UE may receive a configuration by means of different procedures:

[0153] Downlink control information (DCI) is a type of control information that is sent from the BS to the UE on the physical downlink control channel (PDCCH). DCI contains various parameters that2025PF00195

[0154] 11 23.03.2026

[0155] instruct the UE how / when to decode and transmit data on the physical downlink shared channel (PDSCH) and the physical uplink shared channel (PUSCH), such as the resource allocation, the modulation and coding scheme. The UE needs to monitor the PDCCH in each subframe to detect and decode the DCI that is addressed to it.

[0156] Uplink control information (UCI) is a type of control information that is sent from the UE to the BS on the physical uplink control channel (PUCCH) or the physical uplink shared channel (PUSCH). UCI contains various feedback signals that inform the BS about the status and quality of the downlink transmission, such as the HARQ acknowledgments (ACKs), the channel state information (CSI), and the scheduling requests (SRs). The UE needs to encode and transmit the UCI according to the configuration and timing indicated by the BS.

[0157] Sidelink control information (SCI) is a type of control information that is sent from the UE to another UE on the physical sidelink control channel (PSCCH) in device-to-device (D2D) communication scenarios. The main functions of SCI include resource allocation, synchronization, channel quality reporting,.

[0158] Medium access control (MAC) control element (MAC CE) is a type of control information that is sent from the BS to the UE or vice versa on the MAC layer. MAC CE contains various commands or indications that regulate the MAC layer functions, such as the buffer status report (BSR), the timing advance command (TAC), the discontinuous reception (DRX) command, etc. The UE needs to process the MAC CE according to the MAC protocol and the configuration provided by the BS.

[0159] Radio resource control (RRC) command is a type of control information that is exchanged between the BS and the UE on the RRC layer. RRC Command contains various messages that modify / configure RRC parameters and / or initiate, modify, or release the RRC connection or the radio bearers between the UE and the BS, such as the RRC connection setup, the RRC connection reconfiguration, the RRC connection release, the security mode command, the mobility from E-UTRA command, the handover from E-UTRA preparation request, etc. The UE needs to respond to the RRC Command according to the RRC protocol and the configuration provided by the BS.

[0160] Non-access stratum (NAS) messages are used for signalling between UE and core network (CN) on the non-access stratum (NAS) layer. NAS messages enable functionality such as registration, session establishment, security, and mobility management. The UE needs to respond to the NAS Command according to the NAS protocol and the configuration provided by the CN.

[0161] UE parameter update (UPU) is a procedure between the UE and the home network that enables the home network to update configuration parameters in mobile phones and / or USIM using the UDM control plane procedure (TS 23.502). The UE can receive Parameters Update Data from the UDM after the UE has registered in the 5G network.

[0162] Steering of Roaming (SoR) enables the home network to guide the user equipment (UE) when registering on a visited network. For detailed information about the interfaces and registration in the 5G System, refer to 3GPP TS.23.501 (Release 15) and 3GPP TS 24.501 (Release 15). The 5G CP-SOR is2025PF00195

[0163] 12 23.03.2026

[0164] activated during or after registration to update the UE's " Operator Controlled PLMN Selector with Access Technology" list via secure NAS messages, as directed by the home PLMN based on specific operator policies, such as preferred networks or UE location.

[0165] UE configuration update (UCU) is used to update configuration parameters as per TS 23.502 that may include Access and Mobility Management related parameters decided and provided by the AMF, UE Policy provided by the PCF. When AMF wants to change the UE configuration for access and mobility management related parameters the AMF initiates the procedure defined in clause 4.2.4.2. When the PCF wants to change or provide new UE Policies in the UE, the PCF initiates the procedure defined in clause 4.2.4.3. If the UE Configuration Update procedure requires the UE to initiate a Registration procedure, the AMF indicates this to the UE explicitly. The procedure in clause 4.2.4.2 may be triggered also when the AAA Server that performed Network Slice-Specific Authentication and Authorization for an S-NSSAI revokes the authorization.

[0166] Radio access network (RAN) is the part of the cellular system that connects the UEs to the CN via the air interface. The RAN consists of base stations (BSs). A base station (BS) is a fixed or mobile transceiver that covers a certain geographic area, called a cell. In 5G, a BS is also called a gNB (next generation node B). A BS can serve multiple UEs simultaneously within its cell, by using different frequencies, time slots, codes, or beams. A BS also performs functions such as power control, handover control, channel allocation, interference management, etc. A base station can be divided into two units: a central unit (CU) and a distributed unit (DU). The CU performs the higher layer functions, such as RLC, PDCP, RRC, etc. The DU performs the lower layer functions, such as PHY and MAC. The CU and the DU can be co-located or separated, depending on the network architecture and deployment. In cellular systems, a base station may be denoted, based on context, as a cell, or gNB.

[0167] The cell may also refer to the coverage area of a base station. A BS may have different coverage areas such as a macro cell (e.g. several kilometres wide), a pico cell (e.g., for a given location such as a stadium) or a femto cell for a small location (e.g., a home or part of it).

[0168] A base station may communicate with the core network. Since there can be base stations for different cellular systems, different interfaces are required. For instance, a base station, eNB, in a 4G Long Term Evolution (LTE) system (also known as Evolved Universal Mobile Telecommunications Systems (UMTS) Terrestrial Radio Access Network (E-UTRAN)) may interface with the 4G CN known as EPC through the corresponding interface. For instance, a base station, gNB, in a 5G system (i.e., 5G New Radio or Next Generation RAN) may communicate with the 5GC through a different interface. 4G and 5G base stations may communicate with each other directly or through their corresponding core networks.

[0169] The main protocols used between the UEs and the RAN are:

[0170] - The physical layer (PHY), which defines the characteristics of the air interface, such as the frequency bands, the modulation schemes, the coding rates, the frame structure, the synchronization, etc.2025PF00195

[0171] 13 23.03.2026

[0172] - The medium access control (MAC) layer, which regulates the access of the UEs to the shared radio channel, by using techniques such as orthogonal frequency division multiple access (OFDMA), time division duplex (TDD), frequency division duplex (FDD), etc.

[0173] - The radio link control (RLC) layer, which provides reliable data transmission over the radio channel, by using techniques such as segmentation, reassembly, error detection, error correction, retransmission, etc.

[0174] - The packet data convergence protocol (PDCP) layer, which compresses and decompresses the headers of the data packets, encrypts and decrypts the data, and performs data integrity protection.

[0175] - The radio resource control (RRC) layer, which establishes, maintains, and releases the radio bearers between the UEs and the RAN, as well as exchanges the signalling messages for functions such as connection setup, handover, measurement reporting, security activation, etc.

[0176] A transmission / reception communication unit or transceiver may be used by BS and UE to transmit / receive data. Control data may be required for a physical broadcast channel, physical downlink control channel, etc. Data may be for the physical downlink shared channel.

[0177] Data may be encoded by the UE and / or BS to obtain data symbols and / or control symbols that may be exchanged over the wireless interface. The conversion from digital data into analog symbols may be done by the transmission / reception communication unit.

[0178] A medium access control control-element (MAC-CE) is a MAC layer communication element that is used to control the communication between wireless devices. A MAC-CE may be exchanged in a shared channel, e.g., the physical downlink / uplink / sidelink shared channel.

[0179] The communication between a UE and a base station or the communication between UEs (when sidelink is used) may involve the exchange of reference signals. Reference signals may include primary synchronization signal (PSS), a secondary synchronization signal (SSS), a physical broadcast channel demodulation reference signal (DMRS), a channel state information reference signal (CSI-RS). Core network (CN) is the part of the cellular system that connects the RAN to other networks, such as the Internet, or other cellular systems. The CN consists of two main (control / user) domains. The control domain is responsible for providing signalling and control functions for the UEs, such as authentication, authorization, mobility management, session management, etc. The control plane consists of several network functions (NFs), such as the access and mobility management function (AMF), the session management function (SMF), the unified data management (UDM), the policy control function (PCF), the network exposure function (NEF), and the authentication server function (AUSF). The access and mobility management function (AMF) is a NF that handles the registration, deregistration, connection management, and mobility management for the UEs. The session management function (SMF) is a NF that handles the establishment, modification, and release of the sessions for the UEs. The SMF also communicates with the user plane devices to perform functions such as IP address allocation, tunnelling, QoS, etc. The unified data management (UDM) is a NF that stores and manages the user data, such as the2025PF00195

[0180] 14 23.03.2026

[0181] SUPI, the service profile, the subscription status, etc. The policy control function (PCF) is a NF that provides the policy rules and charging information for the UEs, such as the access type, the service level, the data rate, the quota, etc. The network exposure function (NEF) is a NF that exposes the network capabilities and services to external applications and devices, such as the IMS, the Internet of Things (IoT), etc. The authentication server function (AUSF) is a NF that performs the primary authentication with the by using credentials and the SUPI. The user domain is responsible for providing data and multimedia services to the UEs, by using packets and IP addresses. The user plane consists of two main functions: the user plane function (UPF) and the data network (DN). The user plane function (UPF) is a device that forwards the data packets between the UEs and the DNs, as well as performs functions such as tunnelling, firewall, QoS, charging, etc. The data network (DN) is a network that provides access to the services and applications that the UEs request, such as the Internet, the IMS, etc.

[0182] A residential gateway (RG) is a device that connects a home network to an external network, such as the Internet or a cellular system. An RG typically provides functions such as routing, switching, firewall, NAT, DHCP, DNS, VPN, etc. An RG can also support various types of interfaces, such as Ethernet, Wi-Fi, Bluetooth, USB, etc. A cellular-capable RG is an RG that has a cellular interface, such as a UICC slot, a cellular modem, or an antenna, that enables it to access the cellular system as a backup or an alternative to the wired or wireless broadband connection. A cellular-capable RG can provide benefits such as: (1) Enhanced reliability, by switching to the cellular connection in case of a failure or a degradation of the broadband connection; (2) Increased bandwidth, by aggregating the cellular connection and the broadband connection to achieve higher data rates or QoS.

[0183] A multi-SIM subscription is a subscription that allows a user to have multiple SIMs (or eSIMs) that are linked to the same account and service profile. A user can use the multi-SIM subscription to access the cellular system from different devices, such as a smartphone, a tablet, a laptop, or a wearable device, without having to switch the SIM card or the device.

[0184] Overall system: Fig. 1 provides an overall description of a wireless system wherein devices 100, 102, and 128 can play the role of UEs. Device 102 is part of a cellular-capable RG providing connectivity to a home network 129 e.g., by means of a local area network and / or wireless local area network. Device 102 is served by base station 104.

[0185] The RAN 127 comprises base station 103 and serves UE 128. UE 128 may also be a UE to Network relay given access to remote UE 136 that is out of coverage of base station 103. UEs 134 and 136 also communicate with each other via a UE-to-UE relay 135. UE to UE communication via relays is enabled by means of side link communication / PC5 interface.

[0186] Within the RAN, the range of base station 103 is extended via smart repeater 137 and reflective intelligent surface (RIS) 138. Smart repeater 137 and RIS 138 give access to UE 142.

[0187] The RAN 143 includes base station 104 tand serves as wireless access infrastructure for the home network. Base station 104 also serves a mobile access device and / or UE as a UAV 139. UAV 139 may provide connectivity to remote UE 136.2025PF00195

[0188] 15 23.03.2026

[0189] Furthermore, a satellite gateway 141 is shown that connects to satellite 140 and may provide connectivity services to remote UE 136 or UE 100.

[0190] In Fig. 1, the 5G core network 133 may include one or more an AMF 121, SMF 123, UPF 122, AUSF 124, UDM 125, PCF 131, NEF 132 and allows the connection to a data network 130.

[0191] In Fig. 1, a second core network 142, e.g., a legacy core network as a 4G core network, is also shown that may interface with the 5G core network 133, interface with base stations denoted eNB in 4G, and provide a connection to the data network 130. The legacy 4G core network is denoted EPC and may include one or more mobility management entities (MME), a serving gateway, a multimedia broadcast multicast service gateway, a broadcast multicast service center, a packet data network gateway, etc. The mobility management entity may handle the signalling between UE and the 4G CN and may interact with the home subscriber server (HSS) in charge of the storage and management of subscriber data and secrets. The MME may provide connection management, similar to the AMF in 5G. The serving gateway may be used to exchange user internet protocol messages whereby the serving gateway may interact with the packet data network gateway that is connected to IP services. Multiple protocols in 4G and 5G have similar features. For example, the 5G network registration and 4G attach registration message are initially sent by the UE to establish a connection between the UE and the CN, which involves sending an initial request from the UE with its identity and capabilities, receiving an authentication request from the CN with a challenge, sending an authentication response from the UE with a response, receiving an authentication result from the CN with an indication of success or failure, and sending a security mode command from the CN with the selected security algorithms. As a result of this connection establishment procedure, NAS and AS keys are derived from the K_AMF (5G) and K_ASME (4G) where K_AMF is managed by the AMF and K_ASME is managed by the MME. A UE may connect to a serving network or serving Public Land Mobile Network (PLMN). A UE may have a subscription with a home PLMN, and during the registration procedure, the (AMF of the) serving PLMN may forward the registration request to the (AUSF of the) home PLMN that may perform an initial authentication procedure between home PLMN and UE. If the authentication procedure is successful, keys are derived and the home PLMN may share derived credentials with the serving PLMN, including K_SEAF, that may be used to derive K_AMF, from which NAS keys and AS keys are derived. The registration request sent by the UE includes an identifier that can be used by the home PLMN to identify the UE. To prevent privacy vulnerabilities, the long-term subscriber’s identifier known as Subscriber Permanent Identifier (SUPI) may not be exchanged in the clear, but instead, either a Subscription Concealed Identifier (SUCI) or a pseudonym known as GUTI are exchanged with the AMF of the serving PLMN. The AMF of the PLMN may then forward the SUCI to the home PLMN so that the home PLMN decrypts / verifies it.

[0192] Satellite access: Fig. 1 depicts satellite 140 providing access to one or more UEs.

[0193] Satellite access can be performed by means of non-terrestrial devices at different altitudes such as Low Earth Orbit (LEO), Medium Earth Orbit (MEO) or Geosynchronous Equatorial Orbit (GEO) satellites. Other types of non-terrestrial devices may include high-altitude platform station (HAPS) or unmanned2025PF00195

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[0195] aerial vehicle (UAVs) that may comprise a base station. Fig. 3 illustrates different elements including a GEO satellite 302, a MEO satellite 303, LEO satellites 304 and 304’, a UAV 305, all of them potential non-terrestrial mobile access devices giving coverage to wireless device (e.g., a UE) 301. GEO satellite 302 remains static over a given earth position while MEO and LEO satellites move. MEO satellite 303 has a slower moving vector 306 in relation to the earth compared with LEO satellites 304 / 304’ that have a faster moving vector 307 / 307’. A non-terrestrial gateway 308 is included that provides connectivity to the mobile access device via a feeder link 310. A mobile access device provides service to the wireless device via a service link 311. Two mobile access devices in the same orbit may communicate with each other via an intra-orbit-satellite link 312 while two mobile access devices in different orbits may communicate with each other via an inter-orbit-satellite link 313. Fig. 3 finally also includes a terrestrial access device 309 that may also provide connectivity to wireless device 301. The terrestrial access device 309, the wireless device 301, and non-terrestrial gateway are on the earth surface 314.

[0196] Non-terrestrial devices such as satellites distribute system information in specific SIBs, in particular, SIB31 in 4G and SIB19 in 5G. SIB19 information element as defined in TS 38.331 18.2.0.

[0197] ASN1START

[0198] TAG-SIB19-START

[0199] SIB19-rl7:: = SEQUENCE {

[0200] ntn-Conf ig-rl7 NTN-Conf ig-rl7 OPTIONAL, Need R

[0201] t-Service-r!7 INTEGER ( 0.. 549755813887 ) OPTIONAL, -- Need R

[0202] ref erenceLocation-rl7 Ref erenceLocation-rl7 OPTIONAL, -- Need R

[0203] distanceThresh-rl7 INTEGER ( 0.. 65525 ) OPTIONAL, -- Need R

[0204] ntn-NeighCellConf igList-r!7 NTN-NeighCellConf igList-r!7

[0205] OPTIONAL, — Need R

[0206] lateNonCriticalExtension OCTET STRING OPTIONAL, [ [

[0207] ntn-NeighCellConf igListExt-v!720 NTN-NeighCellConf igList-r!7 OPTIONAL — Need R

[0208] movingRef erenceLocation-rl8 Ref erenceLocation-rl7

[0209] OPTIONAL, — Need R

[0210] ntnCovEnh-rl8 NTN-CovEnh-rl8 OPTIONAL, Need R

[0211] satSwitchWithReSync-rl8 SatSwitchWithReSync-rl8

[0212] OPTIONAL — Need R

[0213] NTN-NeighCellConf igList-r!7:: = SEQUENCE ( SIZE ( 1.. maxCellNTN-r!7 ) ) OF NTN-NeighCellConf ig-r!7

[0214] NTN-NeighCellConf ig-r!7:: = SEQUENCE {

[0215] ntn-Conf ig-r!7 NTN-Conf ig-rl7 OPTIONAL, Need R

[0216] carrierFreq-rl7 ARFCN-ValueNR OPTIONAL, Need R2025PF00195

[0217] 17 23.03.2026

[0218] physCellId-rl7 PhysCellld OPTIONAL Need R

[0219] }

[0220] NTN-CovEnh-rl8:: = SEQUENCE {

[0221] numberOfMsg4HARQ-ACK-Repetitions-rl8 BIT STRING ( SIZE ( 4 ) ),

[0222] rsrp-ThresholdMsg4HARQ-ACK-rl8 RSRP-Range OPTIONAL -- Need R

[0223] }

[0224] SatSwitchWithReSync-rl8:: = SEQUENCE {

[0225] ntn-Config-r!8 NTN-Conf ig-r!7,

[0226] t-ServiceStart-r!8 INTEGER ( 0.. 549755813887 )

[0227] OPTIONAL, — Need R

[0228] ssb-TimeOf f set-r!8 INTEGER ( 0.. 159 ) OPTIONAL — Need R

[0229] }

[0230] — TAG-SIB19-STOP

[0231] — ASN1STOP

[0232] SIB19 field descriptions

[0233] distanceThresh

[0234] Distance from the serving cell reference location and is used in location-based measurement initiation in RRCJDLE and RRCJNACTIVE, as defined in TS 38.304

[0020] , Each step represents 50m. This field is only present in an NTN cell.

[0235] movingReferenceLocation

[0236] Reference location of the serving cell of an NTN Earth-moving cell at a time reference. It is used in the evaluation of eventD2 and condEventD2 criteria for the serving cell in RRC_CONNECTED, and location-based measurement initiation in RRCJDLE and RRCJNACTIVE when distanceThresh is also configured, as defined in TS 38.304

[0020] , The time reference of this field is indicated by epochTime in ntn-Config of the serving cell. This field is excluded when determining changes in system information, i.e., changes to movingReferenceLocation should neither result in system information change notifications nor in a modification of valueTag in SIB1. This field is only present in an NTN cell.

[0237] ntn-Config

[0238] Provides parameters needed for the UE to access NR via NTN access such as Ephemeris data, common TA parameters, k_offset, validity duration for UL sync information and epoch. In a TN cell, this field is only present in ntn-NeighCellConfigList and ntn-NeighCellConfigListExt.

[0239] ntn-NeighCellConfigList, ntn-NeighCellConfigListExt

[0240] Provides a list of NTN neighbour cells including their ntn-Config, carrier frequency and PhysCellld. This set includes all elements of ntn-NeighCellConfigList and all elements of ntn- NeighCellConfigListExt. If ntn-Config is absent for an entry in ntn-NeighCellConfigListExt, the ntn- Config provided in the entry at the same position in ntn-NeighCellConfigList applies. Network provides ntn-Config for the first entry of ntn-NeighCellConfigList. If the ntn-Config is absent for any other entry in ntn-NeighCellConfigList, the ntn-Config provided in the previous entry in ntn- NeighCellConfigList applies.

[0241] referenceLocation

[0242] Reference location of the serving cell provided via NTN (quasi)-Earth fixed cell and is used in location-based measurement initiation in RRCJDLE and RRCJNACTIVE, as defined in TS 38.304

[0020] , This field is only present in an NTN cell.

[0243] satSwitch WithReSync

[0244] Provides parameters for the target satellite required to perform satellite switch with resynchronization. This field is only present in an NTN cell and its presence indicates that satellite switch without PCI change is supported in the cell.

[0245] t-Service

[0246] Indicates the time information on when a cell provided via NTN is going to stop serving the area it is currently covering. This field applies for both service link switches in NTN quasi-Earth fixed cell and

[0247]

[0248] feeder link switches for both NTN quasi-Earth fixed and Earth-moving cell. The field indicates a2025PF00195

[0249] 18 23.03.2026

[0250] time in multiples of 10 ms after 00:00:00 on Gregorian calendar date 1 January, 1900 (midnight between Sunday, December 31, 1899 and Monday, January 1, 1900). The exact stop time is between the time indicated by the value of this field minus 1 and the time indicated by the value of this field. The reference point for t-Service is the uplink time synchronization reference point of the

[0251]

[0252] cell. This field is only present in an NTN cell.

[0253] NTN-CovEnh field descriptions

[0254] numberOfMsg4HARQ-ACK-Repetitions

[0255] The number of repetition slots for PUCCH transmission with HARQ-ACK information for Msg4, see clause 9.2.6 in TS 38.213

[0013] , The first / leftmost bit corresponds to the repetition factor 1, the second bit corresponds to repetition factor 2, the third bit corresponds to the repetition factor 4, and the last / rightmost bit corresponds to the repetition factor 8. The repetition factor 1 shall be indicated together with at least one other repetition factor. _

[0256] rsrp-ThresholdMsg4HARQ-A CK

[0257] This threshold is used by the UE for determining the configuration of the MAC entity for PUCCH

[0258]

[0259] repetition for Msg4 HARQ-ACK, as specified in clause 6.2.1 in TS 38.321 [3].

[0260] SatSwitchWithReSync field descriptions

[0261] ssb-TimeOffset

[0262] Indicates the time offset between the SSB from source and target satellite at the uplink time synchronization reference point. It is given in number of subframes. _

[0263] t-ServiceStart

[0264] Indicates the time information on when the target satellite is going to start serving the area currently covered by the serving satellite. The field indicates a time in multiples of 10 ms after 00:00:00 on Gregorian calendar date 1stJanuary 1900 (midnight between Sunday, December 31, 1899, and Monday, January 1, 1900). The exact start time is between the time indicated by the value of this field minus 1 and the time indicated by the value of this field. The reference point for t-ServiceStart

[0265]

[0266] is the uplink time synchronization reference point of the serving satellite.

[0267] A UE in a cellular system performs an initial random-access procedure to connect an access device. The 5G random access procedure is illustrated by means of Fig. 4 wherein 401 represents a user equipment and 402 represents an access device. The access device distributes signals 402. Signals 402 can be distributed periodically or on demand. Signals 402 may comprise the Master Information Block (MIB) transmitted together with / in the physical broadcast channel (PBCH) and the synchronization signals. The MIB comprises:

[0268] MIB::= SEQUENCE {

[0269] systemFrameNumber BIT STRING (SIZE (6)),

[0270] subCarrierSpacingCommon ENUMERATED {scsl5or60, scs30orl20}, ssb-SubcarrierOffset INTEGER (0..15),

[0271] dmrs-TypeA-Position ENUMERATED {pos2, pos3},

[0272] pdcch-ConfigSIB 1 INTEGER (0..255),

[0273] cellBarred ENUMERATED {barred, notBarred},

[0274] intraFreqReselection ENUMERATED {allowed, notAllowed},

[0275] spare BIT STRING (SIZE (1))

[0276] }2025PF00195

[0277] 19 23.03.2026

[0278] MIB and PBCH are transmited as part of a Synchronization Signal Block, and the access device may transmit multiple SSBs through different beams, allowing the user equipment to determine the preferred beam, and once the preferred beam is obtained, retrieve the MIB, and use the information in the MIB to atempt to retrieve System Information Block 1 (SIB1) that may also be distributed periodically. The UE can use the information in SIB1 to perform the random-access procedure selecting a preamble to indicate its intention to access the cell by means of message 404, e.g., preamble transmission. This message may be used to derive a random -access radio network temporary identifier (RA-RNTI). Upon reception of message 404, access device 402 replies with message 405, e.g., a random access response. This message may include a time advance field to adapt the transmission timing, a value matching the preamble used by wireless device 401, and a grant (communication resources) for the wireless device. The access device also assigns a temporary cell radio network temporary identifier (TC-RNTI). Prior to this message 405, the access device may send a PDCCH DCI message assigning resources (a communication grant). This message may be addressed using the RA-RNTI. Upon reception of message 405, wireless device uses the initial grant received in the previous message and the RA-RNTI to transmit a subsequent message 406, e.g, an RRCSetupRequest or PHY layer. This message may include a Contention Resolution Identifier (CRI). This message may be sent in the PUSCH. As a response, access device replies with message 407, e.g., RRCSetup, that includes / repeats the received CRI confirming that the access device has identified the access device. This message includes a Cell RNTI (C-RNTI). Next, wireless device replies with message 408, e.g., an RRCSetupComplete that includes the RegistrationRequest message, and UE capabilities.

[0279] MIB and PBCH are transmited as part of a Synchronization Signal Block, and the access device may transmit multiple SSBs through different beams. Multiple SSBs transmited through multiple beams form an SSB burst. The multiple SSBs in an SSB burst are transmited sequentially in the first part of a frame. SSB bursts are transmited periodically, typically every 20 ms, or more.

[0280] Fig. 5 schematically illustrates an access device 500 transmiting four beams, each of them transmiting an SSB, namely 501, 502, 503, and 504. A wireless device 505 can measure the signal strength, i.e., RSRP (Reference Signal Received Power), of the beams. This is illustrated by means of the graph in Fig. 5 where 501’, 502’, 503’, and 504’ represent the RSRP of beams 501, 502, 503, and 504, respectively, as measured by wireless device 505. Wireless device 505 can use this information to determine which one of the beams is the preferred beam for further communication, e.g., to perform the random access procedure.

[0281] Fig. 6 further schematically illustrates SSB bursts transmited periodically. In this case, each SSB burst comprises four SSBs transmited in the first part / half of every second frame. In this figure, frames are denoted as f, f+1, f+2, f+3,... A frame has atypical duration of 10 ms.

[0282] Resource grid: in a cellular network, such as a 5G network, the resource grid is a structured framework used to allocate and manage communication resources efficiently. It is characterized by a time-frequency matrix where each element, known as a resource element, is defined by2025PF00195

[0283] 20 23.03.2026

[0284] its position in both time and frequency domains. The vertical axis represents frequency, segmented into subcarriers, which are spaced at intervals. The subcarrier spacing can vary depending on the deployment scenario, with common spacings being 15 kHz, 30 kHz, 60 kHz, 120 kHz, 240 kHz, and 480 kHz (corresponding to mu equal to 0, 1, 2, 3, 4, and 5, respectively). The horizontal axis of the grid represents time and is divided into frames, subframes, and slots, each frame has a duration of 10 ms and each subframe has a duration of 1 millisecond. Within these subframes, the time is further divided into slots. For mu, there are 2Amu slots per subframe. Each slot typically spans 14 OFDM symbols. Each resource element in the grid, defined by the intersection of a time symbol and a frequency subcarrier, can carry a small portion of data, control information, or reference signals. These resource elements are grouped into larger units called Resource Blocks (RBs), which span 12 subcarriers in frequency and one slot in time. The allocation of these RBs is dynamically managed.

[0285] Reflective intelligent surfaces (RIS): may be used as part of the wireless infrastructure or as part of the wireless devices. RIS, often referred to as metasurfaces, are advanced materials engineered with sub-wavelength structures that can manipulate electromagnetic waves in a controlled manner. These surfaces consist of an array of unit cells, each capable of adjusting its electromagnetic response through electronic control, thus enabling dynamic alteration of the wavefront of the incident signal. The wireless device can utilize the RIS to fine-tune the reflection properties of the wireless sensing signal, such as phase, amplitude, and polarization. By dynamically adjusting these parameters, the RIS can enhance signal strength, directivity, and overall signal quality. For instance, the RIS can focus the reflected signal towards the transmitter, significantly improving signal reception. This capability is particularly advantageous in urban environments where obstacles and interference are prevalent.

[0286] Technical details of the RIS involve the implementation of tunable elements, such as varactor diodes or microelectromechanical systems (MEMS), in each unit cell. These elements allow real-time reconfiguration of the surface's electromagnetic properties in response to control signals from the wireless device. The control signals can be generated based on real-time analysis of the received signal's quality and contextual parameters, ensuring optimal reflection under varying conditions. The RIS can operate in various frequency bands, including sub-6 GHz and millimeter-wave (mmWave) frequencies, making it versatile for different wireless applications. Additionally, the RIS can incorporate sensing capabilities to monitor the environment and further refine the reflection parameters. For example, integrated sensors can detect changes in temperature, humidity, or the presence of obstacles, and adjust the reflection properties accordingly to maintain high signal quality.

[0287] Quality of Service: a wireless system may be used to transport data belonging to different types of applications such as Machine Type Communication (MTC), Critical Machine Type Communication (CMTC), Enhanced Mobile Broadband (EMB), or Fixed Wireless Access (FWA). MTC (e.g., smart meters, tracking,...) requires low bandwidth and non-latency critical, CMTC (e.g., industrial applications) has strict throughput, latency, and availability needs, EMB (VR / AR, 4K UDH,...) and FWA (e.g., in the home) require high data rate, with low latency, and low end-to-end response time. In wireless2025PF00195

[0288] 21 23.03.2026

[0289] network such as 5G the Quality of Service has to accommodate different applications such as EMB, MTC, ultra-reliable low latency communications. QoS is influenced by the entities involved in the communication, UE, RAN, UPF, and DN. Data exchanges between UE and DN are mapped to QoS flows, and each QoS flow is mapped to a 5G QoS Identifier (5QI) in TS 23.501 (Table 5.7.4-1) that describes resource types, priority, packet delay budget, packet error rate, maximum data burst volume. Network is configured to configure RAN and core network interfaces to achieve the requirements of a 5QI. QoS is applied to a data stream from the wireless physical layer to the core network. Between RAN and UPF, QoS is applied in terms of a QoS flow. QoS in the RAN is managed by means of Data Radio Bearers (DRB). A QoS flow on core network side is created by means of a PDU session establishment accept. The mapping between a QoS flow and a DRB is done by means of SDAP configuration in an RRC message (RRCSetup or RRCReconfiguration) The indication or identifier that connects the whole QoS pipe is called QoS flow identifier. Downlink traffic requires mapping IP messages and the QoS pipe, and this is done by the UPF. For each IP message or packet, the UPF checks (by means of a packet QoS assignment / detection rule) the packet information (source / destination / protocol / type of service / ...) and directs the IP packet to a QoS flow. The packet QoS assignment / detection rule is provided by SMF interacting with PCF. In the uplink, the UE performs a similar task by applying QoS rules provided in NAS messages (e.g., PDU session establishment) by the SMF or are pre-configured / derived by the UE.

[0290] Discontinuous reception (DRX) in cellular networks such as 5G is in two types, Idle mode DRX and Connected mode DRX. In Idle mode DRX, the UE wakes up to monitor for paging messages. If no paging message is detected, it sleeps further. In Connected DRX mode, the UE enters in sleep mode periodically and during the sleep period the UE is not required to monitor the Physical Download Control Channel. The access device configures the UE device with C-DRX parameters.

[0291] Connected DRX approach reduces energy consumption of the device because it does not require monitoring the PDCCH periodically and it also reduces the transmissions of CSI or SRS signals, that also has a positive effect in the network / access devices load. There are two types of DRX cycles, long and short. A long DRX cycle consists of an on period and an off period. The on duration is in terms of milliseconds. The long DRC cycle may be configured or the long DRX cycle and short DRX cycles may be configured. The access device can configure the time (drx-onDurationTimer) during which the UE is awake and goes back to sleep if there is no PDCCH received. The access device can also configure a given drx-LongCycleStartOffiset to start to awake period at a subframe boundary and / or drx-SlotOffset relative to the subframe boundary. If there is activity in an awake period, the UE may remain awake some more time determined by the drx-InactivityTimer. Furthermore, the access device can configure long DRX cycle together with additional DRX cycle which is shorter than long DRX cycle. Configurable parameters include the drx-ShortCycle (duration of the short cycle) and drx-ShortCycleTImer that determines how many short cycles before the device should apply.

[0292] Data scheduling in a cellular network such as a 5G cellular network may be performed by means of a scheduler wherein the scheduler takes as input information such as measurements of UE / 2025PF00195

[0293] 22 23.03.2026

[0294] network, buffer status report, QoS requirements, associated radio bearers, or a scheduling request. In the downlink, data scheduling may be performed by means of dynamic scheduling and semi persistent scheduling (SPS). In dynamic scheduling, every data exchange in the Physical Downlink Shared Channel (PDSCH) is scheduled by means of a downlink control information (DCI) message in the Physical Downlink Control Channel (PDCCH). In SPS, the scheduling is done by means of an RRC message. In the uplink, scheduling can be performed by means of dynamic scheduling and configured scheduling (CS). In dynamic scheduling each Physical Uplink Shared Channel (PUSCH) is scheduled over DCI. In CS, the PUSCH transmission is scheduled via RRC message. Furthermore, a Scheduling Request message may be sent over the PUCCH (Physical Uplink Control Channel) or in an Uplink Control Information (UCI) in the PUSCH (Physical Uplink Shared Channel). An SR may be sent by a UE device when it has data to transmit. Upon reception, the access device can allocate resources (Uplink Grant by means of the Physical Downlink Control Channel. Upon resource allocation, the UE device can transmit data in the Physical Uplink Shared Channel.

[0295] Wireless sensing and integrated wireless sensing and communication: wireless systems are evolving to include wireless sensing capabilities. These wireless sensing capabilities may be implemented e.g. by a radar functionality in wireless communication involving one or more access devices (e.g., base stations (BS)) and / or one or more terminal devices (e.g., UEs). As an example, Frequency Modulated Continuous Wave (FMCW) mmWave radar systems can measure range, velocity, and angle of arrival (if two receivers are available) of objects in the scene which reflect radio waves. Such radar systems emit a chirp signal, e.g., a sine wave that increases in frequency over time. The chirp signal (e.g., a continuous wave pulse) has a bandwidth and a frequency increase rate. Generally, a continuous series of such chirps are emitted. The transmitted and received analogue chirp signals are mixed to generate an intermediate frequency (IF) signal which corresponds to the difference in frequencies of the two signals (outbound and inbound) and whose output phase corresponds to the difference in the phases of the two signals. Each surface of a scene or environment will therefore produce a constant frequency IF signal whose frequency relates to the distance to the surface (i.e., a first distance from the transmitter of the chirp signal to the surface plus a second distance from the surface to the receiver of the chirp signal). To resolve two surfaces at different distances, the two IF signals can be frequency resolved. A longer time window of the IF signal results in greater resolution. As the chirp time is related to its bandwidth (with constant chirp frequency change) the resolution of the radar is related to the chirp bandwidth. The IF signal may then be band pass filtered (to remove signals below some minimal range and frequencies above the maximum frequency for a subsequent analogue-to-digital converter (ADC)) and digitized prior to further processing. The upper frequency sensing range of the bandpass filter and ADC sets the maximum range that can be detected (i.e., IF frequencies increase with range). To detect vibrations, the phase of the IF signal is important, since the phase (i.e., the difference in phases of the transmitted and received chirp signals) is a sensitive measure of small changes in the distance of a surface. Small distance changes can be detected in the phase signal but may be indiscernible in the frequency signal. Moreover,2025PF00195

[0296] 23 23.03.2026

[0297] phase difference measures between two consecutive chirp signals can be used to determine the velocity of the surface. As an example, a fast Fourier transform (FFT) processing can be performed across multiple chirp signals to enable separation of objects with the same range but moving at different velocities. A Fourier transform converts a signal from a space or time domain into the frequency domain. In the frequency domain the signal is represented by a weighted sum of sine and cosine waves. A discrete digital signal with N samples can be represented exactly by a sum of N waves. FFT provides a faster way of computing a discrete Fourier transform by using the symmetry and repetition of waves to combine samples and reuse partial results. This method can save a huge amount of processing time, especially with real -world signals that can have many thousands or even millions of samples. As a further example, angle estimation can be performed by using the phase difference between the received chirp signal at two separated receivers.

[0298] As another option, a channel state information (CSI) can be used, which is a measure of the phases and amplitudes of many frequencies detected at a receiver, thereby forming a complex ‘map’ of the radio environment, including effects of objects within that environment. CSI characterizes how wireless signals propagate from the transmitter to the receiver at certain carrier frequencies. CSI amplitude and phase are impacted by multi-path effects including amplitude attenuation and phase shift, e.g., by the displacements and movements of the transmitter, receiver, and surrounding objects and humans. In other words, CSI captures the wireless characteristics of the nearby environment. These characteristics, assisted by mathematical modeling or machine learning algorithms, can be used for different sensing applications. A radio channel may be divided into multiple subcarriers, as is done e.g. in 5G communication systems (using e.g. orthogonal frequency division multiplexing (OFDM)). To measure CSI, the transmitter may send long training symbols (LTFs), which contain pre-defined symbols for each subcarrier, e.g., in a packet preamble. When those LTFs are received, the receiver can estimate a CSI matrix using the received signals and the original LTFs. For each subcarrier, the channel can be modeled by y = Hx + n, where y is the received signal, x is the transmitted signal, H is the CSI matrix, and n is the noise vector. The receiver estimates the CSI matrix H using a pre-defined signal x and the received signal y after signal processing such as removing cyclic prefix, de-mapping and demodulation. The estimated CSI is then a three-dimensional matrix of complex values and this matrix represents an ‘image’ of the radio environment at that time. By processing a time series of such ‘images’ information on movements, locations and vibrations of objects can be extracted. Such a processing of a CSI matrix can be used for vital signs monitoring, presence detection, and human movement recognition. As an example, neural network like recognition techniques can be used to process the CSI matrix to perform such kinds of recognition.

[0299] It is noted that systems using channel state information (CSI) are somehow related to systems with FMCW mmWave radar. In a CSI-based system, the input signal X may be defined and the receiver may use the received signal Y to obtain H, i.e., as H = (Y - N) / X. In a FMCW mmWave radar, the transmitted signal Chirp X may also be predefined, and the receiver may uses the received signal Y to2025PF00195

[0300] 24 23.03.2026

[0301] obtain a transfer function as H = Y / X. This last step is in fact somehow related to multiplying the locally computed chirp signal and the received chirp signal and applying a bandpass filter. According to various embodiments in this invention, the above-described wireless sensing techniques are implemented in a mobile communication system (e.g. 5G or 6G or other cellular or WiFi communication systems), while the functional coexistence of radar and communication operating in the same frequency bands is configured to avoid interference bandwidths. Thereby, radio sensing can be integrated into large-scale mobile networks to create perceptive mobile networks.

[0302] As another example, the sensing signal may consist of a number of pulses sent, e.g., at specific frequencies and timing (sensing signal parameter information) by a sensing transmitter. The sensing receiver may include a number of bandpass filters that allow identifying the sensing signal parameter information, e.g., timing and frequency of the received pulses. In particular, if the transmitter determines a given pseudo-random sequence of frequency / timing pulses and beams it, e.g., by means of beamforming, in a specific direction, and if the transmitter communicates to the receiver the timing / frequency, in general, the sensing signal parameter information, of the transmitted sensing signal, the receiver can use its bandpass filters to identify the reception of the same transmitted pulses, i.e., sensing signal, based on the received sensing signal parameter information.

[0303] The wireless sensing signal may be part of the synchronization signal block. For instance, the wireless sensing signal may be a reference signal included in the primary synchronization signal or in the secondary synchronization signal. It may consist of a number of reference signals and / or it may be a wide band signal. This wireless sensing signal can allow the access devices to determine the presence of a wireless device. The wireless device may also use this wireless sensing signal to determine the access device that is more suitable to (re-)select.

[0304] Wireless local area network technologies such as Wi-Fi allow devices to connect to the Internet or to each other without using cables. Wi-Fi is based on radio waves that are transmitted and received by a device called a wireless access point (AP). The AP acts as a hub that connects Wi-Fi enabled devices, such as laptops, smartphones, tablets, smart TVs, etc., to a wired network, such as a local area network (LAN) or the Internet.

[0305] The term Wi-Fi is a trademark of the Wi-Fi Alliance, an industry association that certifies products that comply with the IEEE 802.11 standards for wireless local area networks (WLANs). These standards define the physical and data link layers of the communication protocol, such as the frequency bands, modulation schemes, encryption methods, authentication mechanisms, and data rates used by WiFi devices. The most common Wi-Fi standards are 802. Ila, 802.1 lb, 802.11g, 802.1 In, 802.1 lac, and 802.1 lax, which operate in different frequency bands (2.4 GHz, 5 GHz, or both) and offer different levels of performance and compatibility.

[0306] To use Wi-Fi, a device needs to have a wireless network interface card (NIC) that can send and receive radio signals. The NIC scans the available wireless channels and detects the presence of nearby APs. The device then selects an AP to connect to, based on factors such as signal strength, security2025PF00195

[0307] 25 23.03.2026

[0308] settings, and network name (SSID). The device and the AP exchange information, such as the MAC address, IP address, encryption key, and password, to establish a connection. This process is called association. After the connection is established, the device can communicate with the AP and other devices on the same network, or access the Internet through the AP.

[0309] IEEE 802.1 In (Wi-Fi 4) provided new features such as MIMO and frame aggregation to increase throughput. IEEE 802.1 lac (Wi-Fi 5) introduced wider bandwidth and MU-MIMO. IEEE 802.11 ax (Wi-Fi-6) included OFDMA and BSS color or spatial reuse to use spectrum resources more efficiently. IEEE 802.11 ah introduced target wake time (TWT) to support low power loT applications by allowing STAs to go into sleep when not in a wake period after negotiation with AP. IEEE 802.1 Ibe (Wi-Fi 7) aims at improving throughput and latency operating in unlicensed bands between 1GHz and 7.125 GHz. Wi-Fi 7 increases bandwidths up to 320 MHz, 4096 QAM modulation, and supporting up to 16 spatial streams in MU-MIMO with an improved sounding procedure. Wi-FI 7 also enables multiple resource units to be assigned to a single device. Furthermore, it includes an enhanced preamble with a universal SIG filed indicating the PHY version. It also extends the negotiated ack buffer size to 1024 bits. It also enables multilink operation (MLO) enabling multiple links between a station and an access point, for instance an AP can have two radios 2.4 and 5 GHz and use both of them for simultaneous transmission and / or reception with a multi-link capable device (MLD) capable station. Wi-Fi 7 also includes a restricted TWT providing predictable latency by assigning STAs to different rTWT types and making sure that other STAs do not transmit if they do not belong to a given rTWT type. Wi-Fi 7 also include multi-AP coordination performing, e.g., coordinated transmission, beamforming, or joint transmission.

[0310] For instance, in references to Fig. 1, devices 100, 101 and 102 can be Wi-FI access points and device 106 can be a wireless station. Station 106 and access point 101 are MLD and communicate with two links 126. Device 102 is a cellular capable residential gateway.

[0311] Some techniques are illustrated in the context of the efficient and reliable transmission and reception of a signal. Signals may be transmitted for multiple purposes, e.g., to wake up a device, to synchronize a device, to provide a plot signal / reference signal for channel state measurement and / or channel estimation for demodulation, to indicate the device about the reception of data, to perform wireless sensing. In all those cases, it is of paramount importance to perform the measurement of the signal in a reliable and (energy) efficient manner. To this end:

[0312] In embodiment for energy-efficient and reliable reception of a signal or a signal measurement in a wireless system, a first wireless device, which may be a User Equipment (UE) or a station (STA), may receive a configuration of a set of communication resources to be monitored from a second wireless device. The second wireless device, which may be an access point (AP) or a base station (BS), may transmit the signal once or multiple times. When multiple times, it should be at least two transmissions. The first wireless device may determine or receive a configuration that specifies how to monitor (e.g., a mode of monitoring) the set of communication resources to obtain the signal measurement. The first wireless device may then obtain the measurement of the signal. As described in2025PF00195

[0313] 26 23.03.2026

[0314] other embodiments, the measurement of the signal may refer to measurements of the signal such as signal strength, etc. or to the reception of a message included / encoded in the signal. This embodiment can be combined with other embodiments or used independently.

[0315] In a related embodiment that may be combined with other embodiments or used independently, the wireless device may use the information in all communication resources in the first set of communication resources to receive the signal, e.g., by combining (adding the received signals) to reduce the noise, e.g., by maximum ratio combining, e.g., by only decoding the message / signal in the resource with the highest signal strength (e.g., when resources are in different beams), e.g., by decoding the messages in each of the measured signals, followed by majority voting, i.e., selecting the most frequent decoding result, by selecting the first signal whose CRC is verified correctly, etc. When combining the analog signals, the output of the antenna may be passed to a cascade of delay circuits. When the signal is repeated M times, the first received signal goes through M-l delay circuits, the second received signal through M-2 circuits and so on. The output of the delay circuits and the output of the antenna can be “combined” in this manner.

[0316] In a related embodiment that may be combined with other embodiments or used independently, the second wireless device may be a UE / STA that may have been configured by a third access device (e.g., a primary base station) with communication resources to transmit a signal once or multiple times. The second wireless device may then transmit the signal in those communication resources, and the signal transmitted in those resources may be received by the first access device (e.g., secondary base station) that may determine or receive a configuration specifying how to monitor the set of communication resources. This embodiment may be advantageous when transmitting a wake-up signal to first access device, i.e., secondary base station.

[0317] In an embodiment that may be combined with other embodiments or used independently, the signal may be transmitted multiple times in a set of communication sources. The wireless device, which may be a User Equipment (UE) or a station (STA), may receive this signal from another wireless device, which may be an access point (AP) or a base station (BS). The signal may be transmitted in several messages where:

[0318] - each message may comprise the exact same signal to ensure redundancy and increase the probability of successful reception.

[0319] - each message may include the exact signal as pay load but with a different header to differentiate between transmissions and facilitate error detection and correction.

[0320] - each message may include the exact signal as payload but with a different header, wherein some of the fields may be transmitted implicitly.

[0321] - the signal may include a Cyclic Redundancy Check (CRC) for error-checking purposes. - each message may incorporate a message-specific CRC to further enhance error detection capabilities.

[0322] - the signal and / or message may include a preamble and / or postamble.2025PF00195

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[0324] - messages may be transmited according to a regular patern of communication occasions, which helps synchronization and efficient resource allocation.

[0325] - the communication occasions may be scheduled in a manner that allows the first wireless device to reliably detect and decode at least one transmission of the signal.

[0326] In a related embodiment that may be combined with other embodiments or used independently, the second wireless device may transmit multiple signals, e.g., a first signal and a second signal, each signal once or multiple times, e.g., at least Ml times the first signal and at least M2 times the second signal. The first wireless device may also be interested in monitoring the first signal and the second signal. The wireless device may determine or receive a configurating specifying how to monitor (monitoring mode) the communication resources allocated to the transmission of the first signal and second signal so that the first signal and second signal can be determined / obtained in the best possible manner. In particular, repetitions of the first and second signals may be monitored in different manners:

[0327] Altematingly i.e. the monitoring of the first and second signals is interleaved This may be preferred to reduce the chances of being subject to interferences,

[0328] Sequentially, i.e., monitor first the first signal till reception and then monitor the second signal till reception.

[0329] Alternatively or sequentially may refer to the monitoring of time resources, frequency resources, beam resources, code resources, etc. as per other embodiments.

[0330] In another embodiment that may be combined with other embodiments or used independently, the first set of communication resources may comprise communication resources used by the second wireless device to transmit the signal in at least a first communication occasion, and the communication resources of at least a reference communication occasion may use a communication configuration different than the communication configuration of the first communication occasion. The reference communication occasion may be, e.g., a guard-band.

[0331] In another embodiment that may be combined with other embodiments or used independently, the first set of communication resources may comprise communication resources used by a wireless device that may be an access point (AP) or a base station (BS) to transmit the signal in at least a first communication occasion, and the communication resources used for at least a reference communication occasion may use a communication configuration different than the communication configuration of the first communication occasion. The reference communication occasion may be used to transmit a reference message using a specific (reference) communication configuration. The communication configuration may refer to various parameters such as the type of signal transmited, the signal strength, modulation and coding schemes, frequency bands, pre-coding matrix, beams, and time division duplexing (TDD) configurations.

[0332] In another embodiment that may be combined with other embodiments or used independently, the wireless device may monitor and compare the communication configurations estimated and / or measured in, e.g., the first and reference communication occasions. For example, the2025PF00195

[0333] 28 23.03.2026

[0334] wireless device may compare at least one measured communication parameter of the first communication occasion with at least one measured communication parameter in the reference communication occasion. These communication parameters may include signal-to-noise ratio (SNR), received signal strength indicator (RSSI), or error vector magnitude (EVM).

[0335] In an example, the comparison may be performed between different parts of the communication occasions. The wireless device may compare at least one measured communication parameter of a first part in the first communication occasion with a corresponding measured communication parameter of a second part in the same occasion. For instance, the device may measure and compare the preamble, or a part of the preamble, and the payload signal quality.

[0336] In another example, the wireless device may compare at least one measured communication parameter of a first message part transmitted in the first communication occasion with a second message part within the same occasion. The message parts may include different segments of a data packet where each segment may carry different levels of importance or redundancy.

[0337] In an example, the wireless device may also compare the measured communication parameter of the first communication occasion with a configured threshold value. The threshold value may be a numerical value representing a specific signal quality metric that must be met or exceeded for successful communication. This ensures that the wireless device maintains a reliable connection even in varying network conditions.

[0338] In an example, the embodiment may include determining that at least a first message part transmitted in the first communication occasion can be decoded correctly, e.g., the preamble. This determination may involve complex signal processing techniques such as sequence matching, error detection and correction algorithms, which may use CRCs or other error-checking methods.

[0339] In an embodiment that may be combined with other embodiments or used independently, the first set of communication resources may comprise communication resources used by a wireless device that may be an access point (AP) or a base station (BS) to transmit the signal at least in a first communication occasion and in a second communication occasion. The first configuration may require monitoring the second communication occasion if a wireless device that may be a User Equipment (UE) or a station (STA) determines the presence of the transmission of the signal in the first communication occasion and the measurement of the signal does not achieve a minimum quality.

[0340] This embodiment may include the optional step of evaluating one or more communication parameters, such as signal-to-noise ratio (SNR) or received signal strength indicator (RSSI), in the first communication occasion before deciding to monitor the second communication occasion. Additionally, the wireless device may be configured to use advanced signal processing techniques such as error vector magnitude (EVM) analysis to determine signal quality. If the signal quality in the first communication occasion is below the configured threshold value, the wireless device may then proceed to monitor the second communication occasion to ensure a reliable connection.2025PF00195

[0341] 29 23.03.2026

[0342] In an embodiment that may be combined with other embodiments or used independently, the wireless device that may be a User Equipment (UE) or a station (STA) may undertake the following actions:

[0343] - receive a second set of communication resources and a third set of communication resources to monitor: The second and third sets of communication resources may be subsets of the first set of communication resources. This can include frequency bands, time slots, and spatial channels that the wireless device, i.e., UE or STA, needs to monitor. By receiving these resources, the device can ensure it has all the necessary information to maintain a robust connection and optimize its performance in varying network conditions, thereby enhancing overall communication reliability.

[0344] - obtain a second intermediate signal measurement by monitoring the second set of communication resources: This step may involve gathering detailed metrics such as signal strength, signal-to-noise ratio (SNR), error vector magnitude (EVM), and other relevant parameters. These measurements are crucial for understanding the quality of the signal received from the second set of communication resources. Accurate signal measurement allows the device to make informed decisions about future communication strategies, leading to improved signal integrity and reduced transmission errors.

[0345] - determine or receive a second configuration comprising criteria to evaluate the second intermediate signal measurements: The second configuration may include specific threshold values for various signal quality metrics, such as minimum acceptable SNR or maximum allowable error rates. By evaluating these criteria, the device can decide whether it needs to monitor the third set of communication resources. This evaluation process ensures that the device only engages in further monitoring when necessary, conserving resources and enhancing efficiency. For instance, the device may only monitor the third set of communication resources if it has a clear indication that a signal is being transmitted in the second set of communication resources. For instance, the device may only monitor the third set of communication resources if it cannot receive the signal properly based on the second intermediate signal measurement.

[0346] - monitor the third set of communication resources to obtain third intermediate signal measurements: If the criteria of the second configuration are met, the device may proceed to monitor the third set of communication resources. This monitoring may involve advanced techniques such as crossband and temporal analysis, which help in understanding the signal quality across different dimensions and / or set of communication resources. The data from the second and third intermediate signal measurements can be combined to form a comprehensive assessment of the signal, e.g., to reduce the signal to noise ratio. Combination may be done by adding all or part of the measurements, e.g., those parts carrying the same signal. This thorough monitoring ensures that the device can maintain high-quality communication links, adapt to changing conditions, and minimize the likelihood of connection drops.2025PF00195

[0347] 30 23.03.2026

[0348] In a related embodiment that may be combined with other embodiments or used independently, the first configuration and / or the second configuration comprise one or more of:

[0349] - Communication resources used by the first, second, or third set of communication resources,

[0350] - Condition to monitor the signal M times, with M less or equal than N, and which signal / occasions should be monitored. This condition may specify how often the signal should be monitored, the frequency of monitoring the signal to ensure it meets the required quality standards. For example, if M is set to 3, the device will monitor the signal three times within a specified period to gather enough data for accurate quality assessment. For instance, if a signal is repeated N = 8 times, the wireless device may be instructed to monitor the signal M = 4 times that may correspond to the first 4 signal repetitions, or alternating signal repetitions, e.g., 1, 3, 5, 7, or a subset of them. Which signal repetitions need to be monitored may be signaled by means of a codebook, or by means of a bitmap. By setting M < N, where N is a predefined maximum value, the system ensures that resources are not overutilized, thereby maintaining efficiency while guaranteeing reliable communication.

[0351] In a related embodiment that may be combined with other embodiments or used independently, the communication resources may include various types of resources required for signal transmission and reception. For example,

[0352] - Time resources: Specific time slots allocated for transmitting or receiving data to avoid collisions and ensure synchronization in a time-division multiplexing system.

[0353] - Frequency resources: Distinct frequency bands assigned to different communication signals to minimize interference and maximize bandwidth in frequency-division multiplexing systems.

[0354] - Code resources: Unique codes used in code-division multiple access (CDMA) to differentiate between multiple signals sharing the same frequency band.

[0355] - Spatial resources: Different spatial paths utilized in multiple-input multiple-output (MIMO) systems to increase data throughput and reliability.

[0356] - Beam resources: Directional beams formed using advanced antenna techniques to enhance signal strength and reduce interference in beamforming technologies.

[0357] - 0AM mode: Orbital Angular Momentum modes used in advanced communication systems to encode additional information by manipulating the phase of electromagnetic waves.

[0358] Expanding on the technical descriptions:

[0359] - Time resources: In time-division multiplexing (TDM), time slots are allocated to different users or data streams. Each slot represents a specific duration during which the user or data stream has exclusive access to the communication channel. This allocation helps avoid data collisions and ensures that all users or streams can transmit their data without interference.

[0360] - Frequency resources: In frequency-division multiplexing (FDM), the available bandwidth is divided into multiple frequency bands, each assigned to a different communication signal.2025PF00195

[0361] 31 23.03.2026

[0362] This division allows multiple signals to coexist on the same communication medium without interfering with each other, thus optimizing the use of available bandwidth.

[0363] - Code resources: In code-division multiple access (CDMA), each user is assigned a unique code sequence that modulates their signal. These codes are orthogonal, meaning that they do not interfere with each other, allowing multiple users to share the same frequency band simultaneously. The receiver uses the same code to demodulate the signal, separating it from other signals.

[0364] - Spatial resources: In multiple-input multiple-output (MIMO) systems, multiple antennas are used at both the transmitter and receiver ends. These antennas create multiple spatial paths for the signal, increasing the data throughput and reliability of the communication link. By exploiting the spatial diversity, MIMO systems can achieve higher data rates and better performance in challenging environments.

[0365] - Beam resources: Beamforming is a technique used in advanced antenna systems to focus the signal in a specific direction. By controlling the phase and amplitude of the signal at each antenna element, the system can create a directional beam that enhances the signal strength and reduces interference from other sources. This technique is particularly useful in dense urban environments and for long-range communications.

[0366] - OAM mode: Orbital Angular Momentum (OAM) modes involve manipulating the phase of electromagnetic waves to create helical wavefronts. These wavefronts carry additional information, allowing for higher data rates and more efficient use of the communication spectrum. OAM modes are being explored for various applications, including high-capacity wireless communications and optical fiber networks.

[0367] In a related embodiment that may be combined with other embodiments or used independently, a wireless device, e.g., a UE, may be configured (e.g., by an access device) with communication resources determining when / how a signal is transmitted through at least two beams. The wireless device may then receive the signal, e.g., a wake-up signal (WUS) and / or synchronization signal, through the two or more beams. Allocated communication resources in different beams may have different periodicity, this may allow reducing the energy consumption on the device since it may need to monitor less communication resources, while still allowing to monitor multiple beams. The wireless device may use signals measurements obtained from / through both beams to receive / obtain the signal. The wireless device may perform measurements of the signal, e.g., WUS, to determine the preferred beam. The wireless device may report the measurements and / or preferred beam. The wireless device may use the preferred beam to contact the network, e.g., an access device. The network may use the preferred beam to distribute another type of signal, e.g., wake up signal. The measurements that are transmitted may be compressed, e.g., if a signal is repeated 4 times, the absolute value of the first measurement (e.g., signal strength) is transmitted and for the remaining 3 measurements, only the differential value is transmitted.2025PF00195

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[0369] Some embodiments are illustrated by means of Fig. 13 that represents the signaling between a first wireless device 1300 and a second wireless device 1301. Not all the steps may be required. Steps may be repeated and may also be executed in different order. In step 1302, the second wireless device 1301 may provide the first wireless device with a configuration of the first set of communication resources. In step 1303, the second wireless device 1301 may provide the first wireless device 1300 with a first configuration containing the monitoring mode and / or the first wireless device may determine such a first configuration. In step 1304, the second wireless device may distribute signals according to a fourth set of communication resources comprising the first set of communication resources configured in the first wireless device. The first wireless device may perform monitoring activities to obtain measurements of the transmitted signal as described in other embodiments. In step 1305, the first wireless device may report measurements to the second wireless device.

[0370] Fig. 12 schematically represents the first, second, third, and fourth set of communication resources. The fourth set of communication resources 1200 comprises the first set of communication resources 1201. The first set of communication resources comprises the second set of communication resources 1202 and the third set of communication resources 1203.

[0371] Some embodiments are illustrated by means of Fig. 10 wherein the time distribution of signals is illustrated through a first, second, and third beam. The signals distributed through each beam are indicated as 1000, 1001, and 1002, respectively. The signals 1001 transmitted through a second beam are distributed with a higher frequency / shorter period than signals 1000 and 1002 distributed through a first and third beams. The timing of the signals in different beams may be aligned so that a wireless device may monitor multiple signals transmitted through multiple beams. For instance, the six signals within the dashed square 1003 are time aligned so that communication resources used to transmit signals do not overlap. The timing of the communication resources used to transmit a signal through the same beam may depend on the number of beams also transmitting the same signal. For instance, signals 1001’ transmitted through the second beam when the first / third beams do not transmit any signals are repeated faster (communication resources are allocated shortly after each other) compared with signals 1001 transmitted through the second beam when the first / third beams do transmit signals 1000 and 1002, respectively.

[0372] In a related embodiment that may be combined with other embodiments or used independently, the reference communication occasion, which may be adjacent to, e.g., the first communication occasion (i.e., in resources such as time resources or frequency resources that are next to the resources of the first communication occasion), or at a known position, e.g., relative to, e.g., the first communication occasion, or a part of the first communication occasion or a part of the message transmitted in the first communication occasion, first set of communication resources, etc, may need to be configured. This configuration ensures that the reference communication occasion is optimally scheduled and aligned with the overall communication strategy. The configuration process may involve defining specific time slots, frequency bands, message parts, or code sequences that the reference communication2025PF00195

[0373] 33 23.03.2026

[0374] occasion will use. These parameters are typically determined based on the network requirements, the quality of service (QoS) criteria, and the specific application needs. The configuration may be done by means of a configuration message (e.g., RRC message). The configuration may be done using absolute values or relative to the first communication occasion. The reference communication occasion can be a dedicated time slot within a time-division multiplexing (TDM) framework, a particular frequency band in a frequency-division multiplexing (FDM) system, or a unique code in a code-division multiple access (CDMA) environment. The goal is to allocate these resources in a way that maximizes efficiency and reliability while minimizing interference and ensuring seamless integration with other communication occasions.

[0375] In a related embodiment that may be combined with other embodiments or used independently, the first wireless device, e.g., a UE or STA, may transmit to the second wireless device measurements and / or selected parameters used by the first wireless device to monitor the first set of communication resources when obtaining the measurement of the signal. This embodiment is advantageous because it may allow the second wireless device to select more suitable parameters for the first wireless device, e.g., in a subsequent communication round.

[0376] In a related embodiment that may be combined with other embodiments or used independently, a second wireless device such as a base station or an access point, may transmit a configuration of a first set of communication resources to monitor by a first wireless device such as a UE or STA, where the first set of communication resources may be comprised in a fourth set of communication sources used by a wireless device to transmit the signal two or more times; and transmit, a first configuration determining how the first wireless device (e.g., UE / STA) may monitor the first set of communication resources to obtain the measurement of the signal.

[0377] In a related embodiment that may be combined with other embodiments or used independently, the signal may be a reference signal, e.g., synchronization signals, and the measurement of the signal is the measurement of the reference signal. The reference signal may be transmitted multiple N times and a wireless device may be provided with a configuration to monitor all N times or a subset of M of these times, depending on its capabilities. A wireless device may determine based on the configurations whether it is required to monitor all M reference signals or only a subset.

[0378] In a related embodiment that may be combined with other embodiments or used independently, a signal such as a wake up signal or a low power synchronization signal may contain an identifier, e.g., a group identifier. The group identifier may be used to wake-up multiple wireless devices simultaneously, e.g., when multiple wireless devices are supposed to receive a common signal, e.g., a broadcast message, e.g., a SIB, e.g., an emergency message, a public warning system (PWS) message or an ETWS (Earthquake and Tsunami Warning System), or a CMAS (Commercial Mobile Alert System) message.

[0379] In a related embodiment that may be combined with other embodiments or used independently, a wake-up signal may be transmitted (e.g., similar but different than in Clause 10.1.4 in2025PF00195

[0380] 34 23.03.2026

[0381] TS 36.300), e.g., prior to a paging occasion. A group identifier may be determined according to the location, e.g., area that needs to receive the wake-up signal. The identifier itself may relate to the geographic location that requires receiving the wake-up signal, e.g., it may be the center of a circle (determined by the latitude and longitude) and the radius of the circle. Any wireless device within the area may be required to wake up. This approach may allow, e.g., for the specific distribution of emergency messages without requiring the pre-configuration of many groups and this may be more specific than using a common WUS group to wake up all wireless devices monitoring the same WUS / communication resources. This approach may be more accurate. For instance, all or a subset of UEs may be required to monitor some communication resources, e.g., WUS resource, and react when they determine that their / its location falls within the area determined by the group ID transmitted in the communication resource, where the group ID encoded in the transmitted signal represents / encodes / indicates the area. Since this approach may allow addressing / waking up millions of devices simultaneously, devices may be configured to not accept certain group IDs, e.g., group IDs encoding an area larger than a threshold. Additionally or alternatively, wireless devices may be configured with communication resources, e.g., WUS resources, to monitor and identifiers according to the area where they were located. Wireless devices in that area may then wake up when such a WUS is received and may monitor a subsequent message, e.g., the paging message. The paging message may indicate the type of emergency message and may include information about the area that is affected. The paging message may include information to receive the emergency message directly without requiring the acquisition of SIB1. Wireless devices accepting the paging message may then receive the emergency message that may further specify which devices are affected.

[0382] In an embodiment that may be combined with other embodiments or used independently, a (group) wake up signal ((G) WUS) may be used not only in the most recent cell where the wireless device went into inactive / idle state but also in other cells. For instance, if a wireless device goes in inactive / idle state when boarding a boat and going towards the sea, and then an emergency happens, the wireless device may not be able to receive an emergency message. Thus, wake up signals may also need to be monitored from other cells, e.g., NTN cells. For instance, the wireless device may receive a message, e.g., an RRCConnectionRelease, indicating the communication resources, e.g., WUS parameters, it has to monitor. This may be beneficial because a wireless device in inactive / idle mode may not be able to connect to a cell first to obtain SIB(l) including the wake up signal configuration.

[0383] In a related embodiment that may be combined with other embodiments or used independently, the wake-up signal and a low power synchronization signal may be transmitted following a similar common schedule, wherein the wake-up signals fill in gaps in between the low power synchronization signals. This may be advantageous because it allows a receiver to keep synchronized knowing that the synchronization signals occur with a period T_SS, and in between, the receiver may only need to monitor the UP -WUS transmitted with period T WUP, and if no signal is determined go back to sleep. The period T WUP and T_SS may be related, e.g., be a fixed or configurable multiple. The2025PF00195

[0384] 35 23.03.2026

[0385] communication resources (or repetitions) to transmit a first signal (e.g., synchronization signal) may be related to the communication resources (or repetitions) to transmit a second signal (e.g., wake-up signal). The communication resources allocated to a first signal may be implicitly indicated / determined given the communication resources allocated to a second signal, wherein, e.g., an access device may perform the allocation / configuration of the resources to, e.g., a wireless device.

[0386] The above embodiment as well as other embodiments may be illustrated by means of Fig.

[0387] 9 wherein the regular distribution of a first type of signals 900, e.g., low-power synchronization signals is depicted, wherein the first signal is distributed in this specific / illustrative example with period T_SS and each signal is transmitted twice (and thus, communication resources for the transmission of two signals may be allocated). A second type of signal 901, e.g., wake up signal is transmitted with period T_WUS. Communication resources are allocated to a wireless device for monitoring this second type of signal. In this example, this second type of signal are transmitted four times, and a wireless device may be configured to monitor the second type of signal up to four times and the wireless device may determine locally how many times it needs to monitor the signal to obtain / receive it (e.g., as per other embodiments). It is also possible to see that the second type of signal may be transmitted during / after the first type of signal as 902.

[0388] In a related embodiment that may be combined with other embodiments or used independently, the signal may be a low power wake-up signal (LP-WUS) and the measurement of the signal is the measurement of one of a low power wake-up signal. For instance, K LP-WUS monitoring occasions (MOs) may be allocated for a beam, and may be divided into X (X>=1) groups of R LP-WUS MOs. A wireless device may monitor all or some of the MO(s) within the K LP-WUS MOs. For each group of R LP-WUS MOs, the same LP-WUS information may be transmitted as in other embodiments. Different LP-WUS information may be transmitted in different groups of R LP-WUS MOs. Signals transmitted in a group of R LP-WUS MOs may be monitored according to some embodiments.

[0389] In a related embodiment that may be combined with other embodiments or used independently, the measurement of the signal is the measurement of one of:

[0390] - a low power synchronization signal, e.g., a LP-SS transmitted with a low frequency, e.g., every T = 320 ms or more and that is transmitted in short bursts, e.g., every T seconds N LP-SS are transmitted and a wireless device is configured to monitor up to M out of them.

[0391] - an emergency message, e.g., transmitted from an NTN access device N times to ensure its reliable transmission and a wireless device is configured up to monitor up to M transmission occasions;

[0392] - similar to the emergency message, it may be a paging early indication, and / or a paging message, and / or a downlink message;

[0393] - an uplink message, e.g., a Wake-up signal transmitted from a wireless device to an NTN access device. In this case, a first access device (e.g., primary cell) may have configured the wireless device with a number of communication resources to transmit the WUS up to N times and a second2025PF00195

[0394] 36 23.03.2026

[0395] access device (e.g., a secondary cell) may be configured (e.g., by the first access device) to monitor up to M messages / WUS.

[0396] In a related embodiment that may be combined with other embodiments or used independently, the signal may be a wireless sensing signal and the measurement of the signal may be the measurement of the reflection of the wireless sensing signal. The wireless sensing signal may be, e.g., a chirp signal, and the chirp signal of duration T between frequencies fO and fl may be repeated N times. The wireless sensing signal may be distributed by the second wireless device. The first wireless device may receive the reflection of the wireless sensing signal and may be configured to monitor up to M chirps. The wireless device may determine whether an object is being sensed depending, e.g., on the signal strength detected in a first monitoring occasion, e.g., in a first time slot used for wireless sensing. This may be a second set of communication resources. Only if an object is being sensed in such a second set of communication resources and / or the sensing measurement is not of sufficient quality, the wireless device may attempt to perform further wireless sensing in subsequent communication resources (which in this case may be called sensing resources), e.g., a third set of communication resources. Similarly, the wireless device may determine to stop monitoring chirps, e.g., to save energy. It may take the decision to stop monitoring chirps when the wireless sensing measurement fulfils certain criteria, e.g., if the measurements in the second set of communication resources are sufficient, the wireless device may stop further measurements and may skip further monitoring. When a wireless sensing signal is repeated up to M times, e.g., a chirp, the wireless device receiving the reflection of the wireless sensing signal may aggregate some of the repetitions, e.g., in groups of S wireless sensing signals.

[0397] This embodiment may be illustrated by means of Fig. 11, wherein the (wireless sensing) signal transmitted by a second wireless device is illustrated. This signal may comprise a first signal 1100 and / or a second signal 1101 and / or a third signal 1102 and / or a sixth signal 1103. The first signal may comprise a chirp (in general, a wireless sensing signal since it does not need to be limited to a chirp type of signal) 1100-1 and / or a block of information (communication signal 1100-2). The chirp 1100-1 may span from frequencies fO to fl and last T1 seconds. The block of information may contain, e.g., an identifier. The second signal 1101 may include Ml repetitions of a wireless sensing signal, e.g., a chirp. In this case, 3 repetitions are depicted. The third signal 1102 may include M2 repetitions of a wireless sensing signal, e.g., a chirp. In this case, 3 repetitions are depicted. There may be a fourth and a fifth, etc signal similar to the second and third signals. Finally, a sixth signal may be transmitted, e.g., similar to signal 1100. The block of information 1103-2 may signal that the overall signal has finished. A wireless device may be configured to monitor communication resources (or sensing resources) used to transmit, e.g., 1100, 1101, 1102, and 1103. As per other embodiments, 1101 and / or 1102 may not need to be monitored if, e.g., 1100 is not received. 1102 may not need to be monitored if the quality obtained from the signal measurements of 1100 and / or 1101 is sufficient. As per other embodiments, the signal (e.g., chirp) repetitions in, e.g., signal 1101, may be combined to improve the signal quality.2025PF00195

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[0399] Reliability and resilience are important goals when distributing some messages or signals, e.g., emergency messages, e.g., from a NTN devices, and thus, in an embodiment that may be combined with other embodiments or used independently, a first wireless device may be configured with a plurality of occurrences (communication resources) when the different messages / signals (e.g., first message and / or second message) may be distributed. For instance, a first message (e.g., wake up signal and / or paging message and / or emergency message) may be distributed N times in a given set of communication resources, e.g., a period of time T. For instance, N repetitions distributed in time, or N repetitions distributed in different frequencies, or N repetitions distributed in different spatial streams (e.g. precoding matrix), or N repetitions using different codes, or N repetitions in time / using different frequencies / using different codes. This can be advantageous since there are devices with different clock accuracies, devices with different radio capabilities, devices with different radio communication links (e.g., line of sight vs non-light of sight) that may not be able to receive a message properly if it is sent a single time. However, forcing the devices to monitor all N repetitions may be energy consuming.

[0400] Wireless devices may be given a configuration to monitor certain (e.g., a subset M of) resources, e.g., a time window TW within T, or a subset of frequencies, etc. to monitor those messages. The configured resources to monitor, e.g., the time window TW, may also be different for different (types of) wireless devices, e.g., depending on how many times a message may need to be received to ensure a certain level of reliability and resilience for a specific device, depending on the type of device, location, energy budget, etc. For instance, the first message (e.g., paging message or wake up signal) may be a configuration provided by the network when the wireless device connects to it, e.g., by means of an RRC message. For instance, the first message may carry the configuration for the reception of a second message / emergency message. A wireless device may then be required to monitor the configured communication resources knowing that they carry the relevant message. The wireless device may use multiple measurements of multiple messages to aggregate the signal / message, and improve the reliability when retrieving the corresponding message, e.g., first message and / or emergency message.

[0401] In an embodiment that may be combined with other embodiments (e.g., the previous one) or used independently, the resources used to transmit the messages may be limited by, e.g., nontransmission periods, e.g., a non-transmission period before and after a transmission or in the surrounding frequencies. If a wireless device determines that the configured resources used to receive the first and / or emergency messages have a lower signal strength, in general, better fulfil a given criterion, than the resources, e.g. reference signals, surrounding it, the wireless device may be configured (e.g., based on a policy / configuration) to monitor other configured resources. This additional monitoring may be done even if the wireless device is not capable of decoding the signal properly. In general, the criterion may be configurable and may determine the communication features to consider (e.g., signal strength and / or quality of the decoded signal / message and / or whether parts of the message can be decoded, etc), signal strength difference between the configured resources used to receive a signal and surrounding resources triggering further monitoring, whether part or whole of the signal needs to be decodable to trigger further2025PF00195

[0402] 38 23.03.2026

[0403] monitoring, etc. If further monitoring is performed or required in a second set of resources, the wireless device may combine the messages / signals obtained from the first set of resources and second set of resources to obtain a signal of better quality (e.g., better Signal to Noise ratio). This embodiment is advantageous because it allows a wireless device to monitor a first set of resources only, and only if a potential signal is suspected, one or more second set of resources needs to be monitored. This approach provides a good trade-off between energy requirements of the wireless device and reliability when receiving communication signals.

[0404] The above embodiments and other embodiments may be illustrated by means of Fig. 8 that schematically represents a set of resources (e.g., time / frequency) resources and the signaling used to transmit a signal (e.g., wake up signal, paging message, emergency message) in a reliable manner while keeping into account energy consumption of wireless devices. An access device may be configured to transmit a signal of interest, e.g., first message, e.g., paging message or wake up signal, in a set of resources (e.g., at times tl, t2, and t3 using frequencies fl and f2). Furthermore, the resources around some of the selected resources may be kept “empty”, i.e., non-signal, i.e., zero signal (ZS). This may allow a wireless device to better determine whether there is a signal being transmitted in the selected resources. A wireless device may be provided with a policy / configuration determining the set of resources to monitor, e.g., frequencies fl at times tl, t2, and t3, whereby some of the monitoring may only be performed if an event occurs, e.g., when there is an indication that, e.g., some of the resources (e.g., at a first frequency fl and a first time tl) may carry a signal, and this indication may be obtained by comparing one or more communication features, such as, e.g., the signal strength, of the signal in such a first / time resources with the one or more communication features of surrounding frequencies / times. For instance, a wireless device may monitor usually only resources tl / fl unless it is determined that the signal strength in tl / fl is lower than in the surrounding resources,e.g., in reference positions. In this case, the wireless device is required to further monitor fl at t2 and t3 and use that information in all communication resources to receive the messages, e.g., to improve the quality of the received signal. The wireless device may use the information in all communication resources to receive the message, e.g., by combining (adding the received signals) to reduce the noise, e.g., by maximum ratio combining, e.g., by only decoding the message in the resource with the highest signal strength, e.g., by decoding the messages in each of the measured signals followed by majority voting, i.e., selecting the most frequent decoding result, etc. The procedure in Fig. 8 may be used, e.g., to make the reception of wake-up signals / paging messages / early paging / emergency messages more efficient / reliable, messages more efficient / reliable, messages more efficient / reliable, messages more efficient / reliable.

[0405] Uplink repetition

[0406] Some aspects of this invention are illustrated in the context of enhanced coverage in wireless networks, e.g., with the purpose of ensuring that a wireless device can communicate with and / or through an access device.2025PF00195

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[0408] Some aspects of the invention rely on the usage of signal repetition. Signal repetition is a critical technique in wireless communication systems, particularly for enhancing coverage and improving signal quality. When a signal is transmitted multiple times, the probability that it will be successfully received increases. This document explores how signal repetition contributes to better coverage by increasing the signal -to-noise ratio (SNR).

[0409] Signal repetition involves the transmission of the same signal multiple times over a communication channel. Each of these repeated signals can be received independently or combined at the receiver to improve the quality of the signal. When a signal is transmitted multiple times, each instance of the signal is subject to different propagation characteristics such as path loss, fading, and interference. At the receiver, these multiple instances can be processed and combined to reconstruct a more accurate version of the original signal. Methods to achieve this may include: (1) Diversity Combining: Techniques such as maximal-ratio combining (MRC) or equal-gain combining (EGC) are used to combine multiple received signals. This enhances the overall received signal quality by taking advantage of the diversity in the signal paths. (2) Repetition Coding: Redundant copies of (parts of) the signal are transmitted, and error correction algorithms are employed at the receiver to detect and correct potential errors, leading to improved reliability. (3) Time Diversity: The same signal is sent at different time intervals, reducing the likelihood that all instances will be affected by the same fading or interference condition.

[0410] The effectiveness of signal repetition in enhancing coverage is largely attributed to its impact on the signal -to-noise ratio (SNR). SNR is a measure of signal strength relative to background noise, and higher SNR values typically indicate better signal quality and reliability. When a signal is received multiple times, the noise components in each instance are typically independent and uncorrelated. By combining these multiple signal instances, the overall noise effect can be averaged out, effectively increasing the SNR. The mathematical basis for this improvement is rooted in the principles of additive noise reduction, where the combined signal has a higher power compared to the combined noise. Consider a simplified model where a signal X is transmitted N times and received as Y_l, Y_2,..., Y_N. If the noise in each received instance is N_l, N_2,..., N_N, the combined received signal Y can be expressed as Y_1 + Y_2 +...+ Y_N + N_1 + N_2 + N_N. Given that noise N_i is typically zero-mean Gaussian noise, the variance of the noise component in the combined signal is reduced by a factor of N, resulting in an improved SNR.

[0411] In an embodiment that may be combined with other embodiments or used independently, we consider that a wireless device such as a UE or a STA may need to establish a connection with and / or perform a data exchange with / through an access device. The wireless device may then transmit a signal denoted as second signal to a first access device. The wireless device may have and / or have received a configuration denoted a first configuration from the first access device and / or a second access device and / or a third access device. This first configuration may be used to determine how the second signal is transmitted, e.g., how it is “repeated". After transmission of the second signal to the first access device, the wireless device may establish a connection with the first access device and / or a second access device.2025PF00195

[0412] 23.03.2026

[0413] Additionally or alternatively, after transmission of the second signal to the first access device, the wireless device may perform a data exchange with or through the first access device and / or a second access device.

[0414] In an example, a wireless device may receive a configuration via a SIB from a first access device and the wireless device may transmit the second signal, e.g., a preamble, multiple times through two beams to establish the connection with the first access device.

[0415] In an example, a wireless device may receive a configuration via an RRC message from a third access device, the wireless device may transmit the second signal, e.g., a preamble, multiple times through two beams to establish the connection with the first access device.

[0416] In an example, a wireless device may receive a configuration via a SIB from the first access device and the wireless device may transmit the second signal, e.g., a preamble, multiple times through two beams. The first access device may then use the received second signals to obtain measurements, and inform a second access device. The second access device and the wireless device may then connect and / or perform a data exchange.

[0417] In an example, the third access device, e.g., a terrestrial base station, may provide a first configuration, e.g., via an RRC message, to the wireless device. The wireless device may be, e.g., a UE whose user is taking a cruise. The UE may then, in the middle of the ocean, require a call via a second access device, e.g., a GEO satellite. The UE may send one or more second messages to the first access device, e.g., a base station on the cruise or a LEO satellite, to trigger the setup of the connection with the second access device.

[0418] In some examples, some of the access devices may be mobile access devices, e.g., mounted on a vehicle or a UAV or a satellite. In some cases, the wireless device may also be mobile.

[0419] In an embodiment that may be combined with other embodiments or used independently, the wireless device may be capable of receiving a first message with the first configuration to access / communicate / contact the first access device and / or a second access device, and transmitting to the first access device up to N second messages with N equal or greater than 1, through M beams with M equal or greater than 1, and wherein the selection of N and M may be according to the first configuration. The wireless device may select specific beams based on criteria such as signal strength, interference levels, and the quality of the communication channel. This selection process ensures that the transmission is optimized for better performance and reliability. The first configuration may also be stored on the wireless device, e.g., as part of a specification.

[0420] In an embodiment that may be combined with other embodiments or used independently, the wireless device may perform a data exchange with or through the first access device and / or a second access device. This means that the mere fact of sending the second messages by the wireless device and the first access device receiving those second messages may be a sufficient condition to allow the data exchange. For instance, the second messages may be the initial part of a random access procedure. For2025PF00195

[0421] 41 23.03.2026

[0422] instance, the second messages may contain the data that needs to be exchanged, e.g. small data transmission, early data transmission.

[0423] In an embodiment that may be combined with other embodiments or used independently, the wireless device may connect to the first access device and / or second access device upon transmitting at least one of the N second messages. For instance, if the second messages are part of a random access procedure, in general, of a protocol to establish a connection, the successful exchange of the second messages allows establishing the connection. This can allow, e.g., the wireless device to contact the first access device, when required, or the other way around.

[0424] In an embodiment that may be combined with other embodiments or used independently, the path loss between the wireless device and the first access device may be lower than the path loss between the wireless device and the second access device. This may happen, e.g., when the first access device is closer to the wireless device than then second access device. For instance, the first access device may be a LEO satellite, and the second access device may be a GEO satellite. The first access device may be a more suitable candidate to receive the second messages, i.e., the messages that allow triggering the establishment of a connection or a data exchange. The first access device may inform the second access device about the reception of the second messages.

[0425] In an embodiment that may be combined with other embodiments or used independently, it may be beneficial to use a first access device at a first altitude (e.g., UAV or LEO satellite) to establish the communication with a second access device at a second altitude, e.g., a GEO satellite. In some cases, the first access device may be an access device having a first path loss with the wireless device and the second access device may be another access device having a second path loss with the wireless device. For instance, a wireless device may not be able to wake up or trigger the communication with the second access device directly, but the wireless device may be able to do that through the first access device. In particular, the first access device may receive second messages, e.g., wake up signals (e.g., a preamble) to wake up and / or trigger the communication with the second access device. The first access device upon receiving such second messages, e.g., may contact (and optionally provide information / configurations to) the second access device and / or the wireless device to setup / enable the communication between them. This may comprise the second access device transmitting certain signals to the wireless device (e.g., reference signals, e.g., synchronization signals or a SIB (e.g., SIB I) and / or the wireless device transmitting certain signals (e.g., preamble) to the second access device.

[0426] In a related embodiment that may be combined with other embodiments or used independently, the second access device may start said connection and / or data exchange with the wireless device. The first access device may provide the second access device with information to facilitate the connection and / or data exchange. For instance, information detailing the estimated location of the wireless device. For instance, information related to the wake up period of the device. In some cases, this information may be extracted from the second messages received from the wireless device.2025PF00195

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[0428] In a related embodiment that may be combined with other embodiments or used independently, the wireless device may start the connection and / or data exchange with / through the second access device. In some cases, the second access device may start the connection and / or data exchange.

[0429] In a related embodiment that may be combined with other embodiments or used independently, the wireless device may know that the first access device serves as a bridge / relay and / or allows facilitating the connection with the second access device, e.g., the first access device may inform about this capability in a SIB, e.g., SIB 1 or an NTN specific SIB. The wireless device may then use one or more second messages, e.g., a specific uplink wake up signal, to signal this need allowing for the setup of the connection with the second access device and / or data exchange with or through the second access device without the need to connect to the first access device first. In some cases, it may require setting up a connection with the first access device, and then performing, e.g., a handover to the second access device.

[0430] In some cases, the first message may be one or more of:

[0431] an RRC message,

[0432] a SIB, e.g., SIB1,

[0433] received from the first access device, the second access device, and / or the third access device.

[0434] In an embodiment that may be combined with other embodiments or used independently, the wireless device may receive one or more reference signals, e.g., synchronization signals, the wireless device may measure one or more parameters of the reference signals, e.g., synchronization signals, and the wireless device may determine N based on the one or more measured parameters and / or the first configuration, in other words, it may determine the number of times that the second message needs to be repeated. The reference signals, e.g., synchronization signals may be transmitted, e.g., by the first access device. For example, depending on the signal strength of the reference signals, e.g., synchronization signals, the wireless device may determine whether it has to transmit the second message once, twice, and so on. In this invention, in this embodiment and other embodiments, the reference signals may refer to, e.g., synchronization signals, or channel state information reference signals, etc.

[0435] In an embodiment that may be combined with other embodiments or used independently, the wireless device may receive one or more reference signals, e.g., synchronization signals, the wireless device may measure one or more parameters of the reference signals, e.g., synchronization signals, and the wireless device may determine M based on the one or more measured parameters and the first configuration. In other words, the wireless device may determine the number of beams through which the second message needs to be transmitted. Furthermore, it may determine other parameters, e.g., the specific beams that need to be used. For instance, if a wireless device detects only five beams from a base station (e.g., first access device) and with a very low signal strength, the wireless device may determine that it is preferable to transmit the second messages through, e.g., three of them. For instance, the three2025PF00195

[0436] 43 23.03.2026

[0437] that have the highest received signal strength. For instance, the beam that is received with the highest signal strength and the two beams that are adjacent to it.

[0438] In an embodiment that may be combined with other embodiments or used independently, in order to determine the beams and / or number the beams used to transmit / perform the random access procedure through multiple beams, the wireless device may be configured with a configuration (e.g., first configuration) determining one or more of:

[0439] the minimum M_min number of beams that need to / can be used;

[0440] the maximum M max number of beams that can be used;

[0441] a first threshold value for selecting only the minimum number of beams, e.g., if the threshold value refers to a signal strength of a SSB, if the measured signal strength is greater than the threshold value, only the minimum number of beams may be used, but if the measured signal strength is less than the first threshold more than the minimum number of beams may be used, a second threshold for determining which beams are eligible for the transmission through multiple beams. Only beams whose measurements, e.g., signal strength, are greater than the second threshold may be eligible;

[0442] the conditions to use multiple beams, e.g., when the wireless device is moving multiple beams (e.g., more than the minimum) may be used, while if the wireless device is static, multiple beams (e.g., more than the minimum) may not be used. This may require, e.g., configuring a further threshold value, e.g., speed related, so that that UE can measure the current speed, and make choices based on it. For instance, when beam measurements are (highly) variable (e.g., the currently (within a first time window) strongest beam because rapidly less strong, and the currently second strongest beam becomes rapidly (within a second time window) the strongest one), multiple beams may be used;

[0443] a configuration determining how the number of beams used increases with the number of failed random-access procedures. For instance, the first random access procedure may start with the minimum number of beams that can be used, and the number of beams used may increase after one or more failed random-access attempts;

[0444] In an embodiment that may be combined with other embodiments or used independently, a wireless device may receive and use a configuration determining whether beams of a single access device or beams of multiple (up to a maximum of) access devices may be used. For instance, a wireless device may determine that two access devices are potential access devices, in particular, synchronization signals distributed through two beams transmitted from two access devices are potential candidates, e.g., a first and a second access device. The wireless device may perform an initial transmission (transmitting a second message / preamble) targeting two potential access devices. For instance, this may involve transmitting two or more second messages / preambles. The configuration may determine the maximum number of access devices a wireless device may address. For instance, the configuration may determine This embodiment means that a wireless device may only perform the access device selection upon2025PF00195

[0445] 44 23.03.2026

[0446] reception of the random access response from one or both potential access devices. For instance, the access device / beam selection may depend on the signal strength / quality of the random access response. For instance, the transmitted second messages / preambles may indicate the fact that the wireless device is performing a random access procedure through multiple beams / access devices. For instance, the wireless device may include in the second message / preamble towards the first beam / access device an indication of the second beam / access device is trying to access simultaneously.

[0447] In an embodiment that may be combined with other embodiments or used independently, a wireless device may provide feedback about the beams that a wireless device has tried to use in more or less successful manner. For instance, if a wireless device is no mobile (e.g., like a fixed wireless access device, e.g. a residential gateway), or has low mobility, and some beams are less useful (e.g., because previous random access procedures failed), the wireless device may report this information to the network / access device. This may be indicated during the random-access procedure itself (e.g., embedded in a message such as preamble, or Msg 3) and / or in an RRC message. This may help the access device to determine the best beams to use for further communication.

[0448] In cellular networks, a wireless device, e.g., a User Equipment (UE) such as smartphones, tablets, and loT devices utilize antennas to communicate with access devices. The quantity of antennas or antenna panels aries based on the device type and supported frequency bands. For sub-6 GHz frequencies, commonly employed in 4G LTE and 5G networks, wireless devices typically incorporate 2 to 4 antennas. These antennas facilitate Multiple-Input Multiple-Output (MIMO) technology, enabling the UE to transmit and receive multiple data streams simultaneously, thereby significantly enhancing data rates and improving link reliability. For instance, a wireless device equipped with 4 antennas can support 4x4 MIMO, which is ideal for high-throughput, spatial diversity, mitigating signal fading caused by multipath propagation and enhancing overall signal quality. Conversely, for millimeter-wave (mmWave) frequencies in 5G, UEs employ multiple antenna panels, each comprising several antenna elements functioning collaboratively as a phased array. These panels are pivotal for beamforming, a technique whereby the UE concentrates its signal in specific directions to counteract the high path loss and limited range inherent to mmWave bands. A typical 5G smartphone may feature 3 or 4 antenna panels, strategically positioned to ensure coverage regardless of the device's orientation. These panels facilitate beam management, allowing the UE to perform beam sweeping to ascertain the optimal direction for communication, and spatial multiplexing, which augments throughput by transmitting multiple data streams concurrently. Antennas support supplementary modes such as transmit diversity, where multiple antennas transmit the same signal to improve reliability, and receive diversity, where signals from multiple antennas are amalgamated to enhance reception. Furthermore, multiple antennas enable carrier aggregation, combining different frequency bands to increase bandwidth. As cellular technology progresses, the role of antennas in UEs remains crucial, with their number and configuration directly influencing the ability to leverage technologies like MIMO, beamforming, and diversity. This adaptability2025PF00195

[0449] 45 23.03.2026

[0450] ensures that UEs can meet diverse use case demands, from everyday mobile browsing to high-speed data transfers in next-generation networks.

[0451] To this end, in an embodiment that may be combined with other embodiments or used independently, a wireless device may have multiple A antennas / antenna panels, and the wireless device may determine through how many B of the antennas / antenna panels an initial message (e.g., preamble) should be transmitted. For instance, a wireless device may determine the strongest beam / SSB of an access device. However, the wireless device is moving so that the “optimal” antenna may change. To address this issue, the wireless device may transmit the same second message towards the strongest beam / SSB of the access device through multiple antennas / antenna panels. The transmission may be simultaneous, or time multiplexed. The operation of this embodiment may also be controlled by means of a first configuration, e.g., determining whether in a first attempt a single antenna / antenna panel should be used, and how the number of antennas / antenna panels should be increased.

[0452] It is to be noted that throughout this invention, a beam may refer to (1) a beam used by the access device to receive a second message / preamble and / or (2) a beam transmitted by a wireless device to transmit the second message / preamble (e.g., using different antenna / antenna panels).

[0453] In an embodiment that may be combined with other embodiments or used independently, the wireless device may receive one or more reference signals, e.g., on demand or reference signals transmitted, e.g., every T seconds, e.g., 80 msec. The wireless device may use the first configuration to determine a first configuration of transmission parameters of the second messages at time tO (e.g., after receiving the first set of reference signals). If no answer is received, the wireless device may determine a second configuration of transmission parameters of the second messages, e.g., at time tl (e.g., after receiving a second set of reference signals). For instance, the first time at time tO, a single second message is transmitted. For example, the second time at time tl, 2 second messages are transmitted through a single beam. For example, the third time at time t2, 4 second messages are transmitted through two different beams. This embodiment represents an adaptive approach that allows adjusting the transmission parameters (of the second messages) depending on the communication link. This approach may provide a suitable balance between enhanced coverage and energy consumption.

[0454] In an embodiment that may be combined with other embodiments (e.g., the previous two) or used independently, the one or more parameters that may be measured from reference signals, e.g., synchronization signals may comprise one or more of:

[0455] signal strength of each reference signal,

[0456] signal quality of each reference signal,

[0457] measured frequency shift of each reference signal,

[0458] angle of arrival of the reference signal.

[0459] In some examples, the time / timing between second messages may be determined based on the first configuration. This timing may be, e.g., for repetitions through a same beam, and / or through repetitions through two or more beams.2025PF00195

[0460] 46 23.03.2026

[0461] In some examples, the wireless device may transmit the second messages through M different beams according to a beam transmission mode and the beam transmission mode is one of:

[0462] (1) simultaneously, i.e. two or more second messages are transmitted through two or more beams simultaneously;

[0463] (2) sequentially, i.e., second messages are transmitted through a single beam or through multiple beams one second message after another, for instance, N 1 second messages are firstly transmitted through a first beam and then N2 second messages are transmitted through a second beam;

[0464] (3) alternating, i.e., second messages are transmitted through different beams in an alternating manner, for instance, N1 second messages are firstly transmitted through a first beam, then N2 second messages are transmitted through a second beam; then N1 second messages are transmitted through the first beam, then N2 second messages are transmitted through the second beam; etc.

[0465] (4) increasing, i.e., an increasing number of second messages are transmitted, for instance, one second message is firstly transmitted through a first beam, then one second message is transmitted through a second beam; then two second messages are transmitted through the first beam, then two second messages are transmitted through the second beam; etc.

[0466] The beam transmission mode may be configured, e.g., by means of the first configuration. The parameters used in the beam transmission mode may also be configurable.

[0467] In some examples, at least one of the N second messages encodes the value N. This may be advantageous so that the receiving access device can determine the number of repetitions of the second message.

[0468] In some examples, the second message transmitted in k position encodes the value k. For instance, if the second message is transmitted twice, the first transmitted second message may encode the number “1” and the second transmitted second message may encode the number “2”. For instance, it may encode the temporal position when the multiple second messages are time multiplexed. For instance, the second messages may encode different sequence numbers (related to the position term before), where a second message with a lower sequence number is transmitted at the same or at an earlier time than a second message with a higher sequence number.

[0469] In some examples, a first (or current) second message encodes the beam identifier used to transmit a second (or subsequent) second message. In other words, if the wireless device decides to transmit the second messages through beams bl and b2, the second messages transmitted through beam bl may include the identifier of b2, and vice versa. In some cases an access device may have many beams, e.g., 64 beams and encoding a beam identifier requires therefore 6 bits. However, a wireless device may indicate related beams in a relative manner. For instance, if a wireless device selects beams 33, 34, and 35, and the main choice is beam 34 (e.g., because it is the beam for which the measured signal strength is the strongest one), beam 34 may be identified by means of 0, beam 33 may be identified by the relative position to the main beam, i.e., -1, and beam 35 may be identified by the relative position to the2025PF00195

[0470] 47 23.03.2026

[0471] main beam, i.e., 1. This approach reduces the overhead. This approach also allows identifying which beams are preferred and / or their relative position to the preferred one.

[0472] In some examples, the same second message (e.g., preamble) may be transmitted in each of the selected beams. In some cases, different second messages (e.g., different preambles) may be sent in different beams. In some cases, the second messages transmitted in different beams may be variations of a same root message. For instance, a cyclic rotation of a root message. For instance, if the strongest beams are beam 33, 34, and 35, and a root sequence is 000001000000, then the root sequence may be transmitted as it is to beam 34, and it may be transmitted with a left cyclic rotation towards beam 33 (previous beam), e.g., as 0000 10000000, and it may be transmitted with a right cyclic rotation towards beam 35 (next beam) e.g., as 0000 0010000.

[0473] In general, the invention may be used to enhance coverage during random access. The second messages may be preambles transmitted multiple times / through different beams. A challenge is that the access device may consider that the multiple transmissions in different beams of the second messages originate in multiple wireless devices, and not a single one. To deal with this,

[0474] In an embodiment of the invention that may be combined with other embodiments or used independently, in some examples, a first (or current) second message encodes the parameters used to transmit a second (or subsequent) second message. It is to be noted that in some variant of this embodiment the second second message may be sent prior to the first second message, or even simultaneously. This embodiment is a generalization of other embodiments, e.g., the previous one, since other parameters may be also indicated, e.g., transmission power, and / or transmission time. For instance, the transmission power may be included, e.g., it may be included as a relative factor to the transmission power of the current beam. For instance, the transmission time of another second message may be encoded, e.g., relative to the transmission time of the current second message. For instance, a first second message (first preamble) may also encode an identity of the second second message (e.g., a second preamble). Additionally, or alternatively, the first and second second messages may be related, e.g., be the same and / or a simple modification / transformation (e.g., a cyclic rotation) of the same message. This may allow an access device to determine what to look for and / or when to search for the related second messages and / or determine whether it is capable of decoding them.

[0475] In some examples, the N second messages encode one or more identifiers, and the one or more identifiers are associated to the N second messages. Identifiers may include a wireless device identifier or a second message set identifier that links multiple second messages together. This may be useful, e.g., to determine that a group of second messages are associated to each other, e.g., are transmitted by the same wireless device.

[0476] In some examples, the second messages may be related to each other by the content. For instance, a root second message may be selected to be transmitted through a first second beam, and second messages in distributed through a second second beam and / or a third second beam may correspond to a transformation of the root second message, e.g., a cyclic shift.2025PF00195

[0477] 48 23.03.2026

[0478] In general, the type of the transformation (e.g., cyclic shift to the right or left and / or amount) of the root second message (e.g., root Zadoff-Chu sequence) may depend on the spatial location of the beams and / or the communication resources / transmission occasions selected.

[0479] For instance, if the second second beam is (spatially) located before the first second beam, the cyclic shift may be to the left b bits. For instance, if the third second beam is (spatially) located after the first second beam, the cyclic shift may be to the right b bits.

[0480] For instance, if the wireless device may select transmission occasions

[0481] 11000000

[0482] 00011000

[0483] 00000110

[0484] These transmission occasions may be defined / determined by means of a codeword out of 24 transmission occasions. The transmission occasions may be mapped to beam and time resources. For instance, a first, second, and third beams, and 8 time slots. For instance, the first codeword may be assigned to the first beam, the second codeword part may be assigned to the second beam, and so on. The second beam may be the strongest one (currently measured), thus, the root sequence may be transmitted in the communication resources of the second beam. Thus, the root sequence may be transmitted in the central time resources assigned to the second beam, e.g., time slot 4 and 5. For instance, the first beam may be spatially located on the left, so the root sequence may be cyclic shifted to the left y*X bits, where y=3 corresponds to the number of bit shifts between the the first part of the codeword (assigned to the first beam) and the second part of the codeword (assigned to the second beam). Similarly, the third beam may be spatially located on the right, so the root sequence may be cyclic shifted to the right y’*X bits, where y=2 corresponds to the number of bit shifts between the second part of the codeword (assigned to the first beam) and the third part of the codeword (assigned to the third beam). X may be the (unit of) number of bits that are cyclic shifted.

[0485] In some examples, the second messages may be related to each other by the communication resources and / or transmission occasions used to transmit the second messages. For instance, the wireless device may have a configuration determining sets of communication resources / transmission occasions (e.g., determined by means of a codeword / codebook as in other embodiments / examples) that may be used together to transmit the N second messages. Thus, all second messages transmitted in those N transmission occasions will consider as related.

[0486] In some examples, the second messages may be related to each other by the communication resources and / or transmission occasions used to transmit the second messages. For instance, the wireless device may have a configuration determining sets of communication resources / transmission occasions (e.g., determined by means of a codeword / codebook as in other embodiments / examples) that may be used together to transmit the N second messages. Thus, all second messages transmitted in those N transmission occasions will consider as related.2025PF00195

[0487] 49 23.03.2026

[0488] In some examples, the transmission occasions / communication resources for transmitting one or more second message (preambles) multiple times may be a different than transmission occasions / communication resources for transmitting a second message (preamble) a single time. This allows the access device to differentiate between a wireless devices transmitting multiple second messages and wireless devices transmitting a second message a single time.

[0489] In an embodiment that may be combined with other embodiments or used independently, the beams selected to transmit the second messages are selected based on contextual information, e.g., the moving direction of the wireless device and / or first access device. For instance, even if a beam seems to be weak (based on the received reference signals, e.g., synchronization signals), if the wireless device determines that (e.g., based on their moving direction) the beam is likely to become more suitable for further communication, the wireless device may select such a beam for the transmission of second messages as well.

[0490] In an embodiment that may be combined with other embodiments or used independently, the wireless device may be configured with an AI / ML model and the AI / ML model may allow the wireless device to determine suitable parameters for the transmission of the second messages, e.g.: N, M, selected beams, etc. The AI / ML model may also be configured as part of the first configuration or independently of it. The usage of such an AI / ML model for this task may also be enabled and / or disabled by an access device. The usage of such an AI / ML model for this task may also be made dependent to its performance, e.g., be disabled if no connection and / or data exchanged can be performed.

[0491] In a related embodiment that may be combined with other embodiments or used independently, a wireless device may have historical data (e.g., the last t ms or the last t seconds) about the beams that have the best performance, e.g., the beams / SSBs measured from an access device. The wireless device may have an AI / ML model / function that may allow predicting the beams / SSBs that are predicted to have the best performance at a subsequent point of time.

[0492] For instance, if an access device has a fixed beam / SSB configuration (i.e., beams / SSBs do not move and cover a fixed area) and wireless device moves (and / or the wireless access device moves), the wireless device may observe / measure how based on their relative movement some of the beam measurement values (e.g., signal strength) increase / decrease. The wireless device may then select one or more beams based on such predictions for the transmission of the second messages.

[0493] For instance, when sending one or more second messages (e.g., preambles) for the initial random access, the wireless device may select the beam that currently offers the best communication link (e.g., measured with the highest signal strength) and the beam that is expected to offer the best communication link at a subsequent time (e.g., when receiving a later message, e.g., a third message.

[0494] In an embodiment that may be combined with other embodiments or used independently, the wireless device may transmit one or more second messages (e.g., preambles) to an access device through a first beam. The one or more second messages may include an indication of a second beam that may be used by the access device to transmit a third message (e.g., random access response) to the2025PF00195

[0495] 50 23.03.2026

[0496] wireless device (in general, to perform a data exchange between wireless device / access device). This embodiment may apply, e.g., when the wireless device has an AI / ML model that allows predicting which beams may be more suitable for the communication in the uplink (e.g., transmit the second message) and downlink (e.g., receive the third message). In this case, instead of having to transmit the second message through both the first and second beams, the uplink is done through the first beam and the downlink is done through the second beam. The wireless device may have a configuration (e.g., first configuration) determining whether this operation is feasible / allowed. This operation may be triggered based on one or more conditions, e.g., as in previous embodiment.

[0497] In an embodiment that may be combined with other embodiments or used independently, the second messages are transmitted through at least a wide beam and at least a narrow beam. This may be beneficial because the (first) access device may monitor, e.g., first, the wide beam, and then use a “hint” in the signal (e.g., a second message) received through the wide beam, to monitor the corresponding narrow beam or narrow beams. This is illustrated by means of Fig. 15 as elaborated below.

[0498] In an embodiment that may be combined with other embodiments or used independently, an access device, upon reception of one or more second messages may transmit to the wireless device multiple third messages, e.g., L third messages with L equal or greater than 1. The wireless device may therefore be adapted to receive up to L third messages. The third messages may be used to confirm / setup the connection. The third message may be, e.g., a random-access response.

[0499] In a related embodiment that may be combined with other embodiments or used independently, the access device may transmit the third messages in different manners, e.g., one or more of:

[0500] one or more third messages after the reception of each second message, this may be advantageous because the wireless device receives feedback as early as possible from the first access device and it can allow for a more efficient communication;

[0501] up to L third messages after the reception of all N second messages, this is advantageous because it allows the first access device to obtain the second message in the most reliable manner;

[0502] the third messages may be transmitted through all the beams used for the reception of the second messages, this ensures path diversity in the transmission back to the wireless device;

[0503] the third messages may be transmitted through a selection of the beams used for the reception of the second messages, e.g., one or more of those beams in which the second message was decoded or was received fulfilling certain criteria, e.g., high enough received signal strength, e.g., the best beam, this allows reducing resource needs and performing beam selection.

[0504] In a related embodiment that may be combined with other embodiments or used independently, the wireless device may be adapted to perform the opposite actions of the last embodiment, e.g.: receive at least one third message after the transmission of a second message; and / or receive up to L third messages after transmitting all N second messages, etc.2025PF00195

[0505] 51 23.03.2026

[0506] In a related embodiment that may be combined with other embodiments or used independently, the wireless device may be adapted to perform the data exchange with or through the first access device and / or second access device as a result of receiving at least O third messages, with O equal or greater than 1. In other words, the wireless device may require receiving multiple third messages to communicate further. This may be advantageous to ensure a sufficient link quality. The value O may be encoded in one or more of the third messages, and / or be provided by means of the first configuration, etc.

[0507] In an embodiment that may be combined with other embodiments or used independently, the wireless device may stop transmitting any further second messages as a result of receiving at least one third message. This may be advantageous to reduce latency and energy consumption while ensuring higher reliability and coverage.

[0508] In a related embodiment that may be combined with other embodiments or used independently, the wireless device may stop transmitting any further second messages through a second beam as a result of receiving at least one third message through a first beam. This may allow the wireless device to reduce energy consumption. When the wireless device receives the third message through the first beam, the wireless device may understand that the second beam is not a preferred beam for further communication.

[0509] In a related embodiment that may be combined with other embodiments or used independently, when a wireless device uses two or more beams to send the second messages, the wireless device may determine the preferred beam for further communication based on the beam used by the access device to provide the third message. This embodiment provides therefore an implicit indication of the preferred / chosen beam by the access device.

[0510] In a related embodiment that may be combined with other embodiments or used independently, the second message may be one or more of:

[0511] a preamble to perform a random-access procedure,

[0512] an uplink wake-up signal,

[0513] a message to complete the setup of a radio resource control protocol.

[0514] In a related embodiment that may be combined with other embodiments or used independently, the third message is one of:

[0515] random access response message.

[0516] an RRC Registration Request,

[0517] an RRC Connection Complete,

[0518] an RRC Connection Reconfiguration Complete,

[0519] In a related embodiment that may be combined with other embodiments or used independently, the wireless device may determine a preferred beam for further communication based on one or more of:

[0520] an indication (implicit or explicit) on at least one third message and / or2025PF00195

[0521] 52 23.03.2026

[0522] measurements (e.g., signal quality / strength) of the third messages and / or measurements (e.g., signal quality / strength) of the reference signals, e.g., synchronization signals.

[0523] This approach may provide a more reliable selection mechanism when selecting a communication beam since it is based on not only on the choice of the wireless device but also on, e.g., the indication of the access device and / or measurements of both the wireless device and the first access device.

[0524] In a related embodiment that may be combined with other embodiments or used independently, the first configuration may comprise one or more of:

[0525] transmission power of the reference signals, e.g., synchronization signals, load indication of the first access device,

[0526] load indication of the second access device,

[0527] indication of the maximum N, M, L, and O values allowed and / or used by the first access device and / or second access device,

[0528] beam transmission mode,

[0529] timing between transmission of second messages when sent through the same and / or different beams (e.g., referring to T_l, T_2, T_3, T_4, T_5 as per Fig. 16),

[0530] one or more values (allowing) determining the N value based on the one or more measured parameters and / or a fixed configuration,

[0531] one or more values (allowing) determining the M value based on the one or more measured parameters and / or a fixed configuration,

[0532] adapting rules that allow adapting the different parameters, e.g., N, M,... depending on the context, e.g., when no answer (no third message) was received after a first transmission of N second messages,

[0533] transmission parameters as a function of N and / or M, wherein the transmission parameters may comprise one or more of transmission power, timing, encoding, and modulation of one or more of the N second messages,

[0534] an AI / ML model used to determine suitable parameters, e.g., N, M, selected beams, or timing values;

[0535] monitoring / transmission mode;

[0536] communication parameters of, e.g., second messages, such as time location, frequency location, pre-coding matrix of the spatial stream, etc.

[0537] In a related embodiment for enhanced coverage when providing access to a network that may be combined with other embodiments or used independently,

[0538] the first access device may receive one or more times a second message from a first wireless device attempting to connect to the network,2025PF00195

[0539] 53 23.03.2026

[0540] the first access device may transmit L third messages with L greater or equal than 1 upon reception of one or more second messages, and

[0541] the first access device may perform or enable a data exchange with the first wireless device.

[0542] In a related embodiment for enhanced coverage when providing access to a network that may be combined with other embodiments or used independently,

[0543] the first access device may receive one or more times a second message from a first wireless device attempting to connect to the network,

[0544] the first access device may transmit an indication to the second access device, wherein the indication indicates the reception of the one or more second messages from the first wireless device.

[0545] In a related embodiment for enhanced coverage when providing access to a network that may be combined with other embodiments or used independently,

[0546] the second access device may receive an indication from a first access device, wherein the indication may indicate the reception of the one or more second messages from the wireless device.

[0547] the second access device may transmit L third messages with L greater or equal than 1 upon reception of the indication, and

[0548] the second access device may perform or enable a data exchange with the wireless device. In a related embodiment for enhanced coverage when providing access to a network that may be combined with other embodiments or used independently, the first access device may transmit one or more of:

[0549] reference signals,

[0550] synchronization signals,

[0551] a SIB message containing a first configuration,

[0552] an RRC message containing a first configuration,

[0553] an RRC Registration Request,

[0554] an RRC Connection Complete,

[0555] an RRC Connection Reconfiguration Complete,

[0556] In a related embodiment for enhanced coverage when providing access to a network that may be combined with other embodiments or used independently, the first access device may determine a preferred beam for communication with the wireless device based on the one or more received second messages.

[0557] Fig. 14 describes a procedure according to several embodiments of the invention. Entities 1401, 1402, and 1403 represent the wireless device, the first access device and the third access device, respectively. The arrows represent signals or messages that may be transmitted once or multiple times, the order may also change, and not all signals may be always required. Message 1404 represents a first message in which either the first access device 1402 or the third access device provide the wireless device with the first configuration. Signal 1405 represents the regular distribution of reference signals, e.g.,2025PF00195

[0558] 54 23.03.2026

[0559] synchronization signals by the first access device. The wireless device may measure those reference signals, e.g., synchronization signals. Signal 1406 represents the transmission of the second messages (e.g., N second messages through M beams, e.g., N preambles through M beams). Signal 1407 represents the transmission of multiple third messages, e.g., the transmission of multiple copies of the random access response. Messages 1408, 1409, and 1410 represent subsequent messages in the random access procedure, e.g., RRCSetup Request, RRCSetup, and RRCSetupComplete, respectively.

[0560] Fig. 15 schematically describes the communication between the first access device 1500 and the wireless device 1507 using multiple beams. The first access device may have / use one or more wide beams 1505 and 1506. The first access device may have / use one or more narrow beams 1501, 1502, 1503, 1504. Similarly, the wireless device may have one or more wide beams 1511 and / or one or more narrow beams 1508, 1509, and 1510. The first access device may transmit multiple first messages (denoted as 1513) through several of its beams. The wireless device may transmit multiple second messages (denoted as 1512) through several of its beams. The first access device may reply with multiple third messages (denoted as 1513) through several of its beams.

[0561] Fig. 16 schematically describes the transmitted second messages through three beams Beam A, Beam B, and Beam C. Beam B and Beam C may be, e.g., narrow beams and Beam A may be, e.g., a wide beam. Beam A and Beam B may be, e.g., narrow beams and Beam C may be, e.g., a wide beam. The figure illustrates that different beams may transmit second messages with different periodicities. For instance, second messages transmitted through Beam A have a periodicity of time T_2 and second messages transmitted through Beam B have a periodicity of time T_1. It is to be noted that second messages may be transmitted in groups. For instance, 1600 represents a group of two second messages transmitted through Beam B. For instance, 1603 represents a group of six second messages transmitted through all three beams. Second messages transmitted within a group may be repeated with a given periodicity, e.g. 1600 has periodicity T_3. For instance, second messages transmitted through the same beam in group 1603 are repeated with period T_4. For instance, second messages transmitted (independently of the beam used) in group 1603 are repeated with period T_5.

[0562] Fig. 17 further illustrates a scenario related to Fig. 15 wherein the wireless device 1507 is moving. At time tO is at location pO and at time tl it is at location p 1. This embodiment illustrates a further usage of the transmission of the second messages through multiple beams. When the wireless device remains static at location pO, the choice of transmitting the second messages 1512 through beams 1509 and 1510 is good, but if the wireless device moves that choice may not allow a good connection and transmitting the second messages 1514 through beam 1508 is more suitable. This figure illustrates therefore the advantages of performing the transmission of the second messages through beams that may be suitable for the communication based on the relative movement of the wireless device and first access device.

[0563] It is to be noted that the relative movement of the devices may be described as a prediction of the beams that are expected to have better performance. For instance, in Fig. 17, at tO,pO,2025PF00195

[0564] 55 23.03.2026

[0565] beams 1501, 1502, 1503, 1504 are such that beams 1502 and 1503 have the highest signal strength. The analysis of the beam measurements overtime may allow predicting that at time tl, pl, beams 1501, 1502, 1503, 1504 are such that beams 1503 and 1504 have the highest signal strength.

[0566] Fig. 18 schematically illustrates some embodiments of the invention wherein 1507 represents a wireless device having a single beam 1510. 1500 represents an access device having three beams 1501, 1502, and 1503. Beam 1502 is the strongest one as measured by wireless device 1507. Wireless device 1507 may determine codeword

[0567] 11000000

[0568] 00011000

[0569] 00000110

[0570] Determining 6 transmission occasions (highlighted as dark rectangles 1800) out of 24 possible transmission occasions 1603. Not selected transmission occasions are indicated as white rectangles. Transmission occasions assigned to beam A (1501), beam B (1502), and beam C (1503) are indicated as 1602, 1601, and 1600 respectively. Transmission occasions are also distributed in time, wherein transmission occasions on the left occur before than transmission occasions on the right.

[0571] Further aspects of the invention are described in the context of massive random access and coverage enhancements.

[0572] In massive random access, the goal is to increase the number of wireless devices that perform random access simultaneously. This is important since future wireless networks may require, e.g., supporting increasing number of wireless devices and / or supporting non-terrestrial devices covering a large area, etc.

[0573] Coverage enhancements aim at ensuring the communication between a wireless device and an access device can be established (e.g., during random access) and / or is feasible despite distance between wireless and access devices, low strength and / or quality of the exchanged signals.

[0574] In cellular networks, random access is performed by transmitting a second message, e.g., preamble, to the network / access device. This comprises several steps.

[0575] 1. Determining the preamble: The preamble is a carefully chosen signal. In a typical cell (e.g., in LTE), there are 64 possible preambles. These are derived from specific sequences with properties explained below. The wireless device learns about these preambles from the access device, which broadcasts configuration details, e.g., in. SIB (or first message). This includes parameters like the root sequence index and zeroCorrelationZoneConfig, which define the set of preambles available in that cell. The wireless device may perform contention-based or contention-free random access. In Contention-Based Random Access, the wireless device (UE) randomly picks one of the 64 preamble indices. This randomness can lead to multiple wireless devices choosing the same preamble, causing a potential collision (resolved later in the procedure). In Contention-Free Random Access, the access device assigns a specific preamble index to the wireless device, typically for scenarios like handovers, where the network needs to ensure a dedicated signal. For2025PF00195

[0576] 23.03.2026

[0577] this explanation, we’ll focus on the contention-based case, as it’s more common. So, the wireless device starts by selecting a preamble index — say, number 42 out of the 64 options — based on a random choice in the contention-based scenario.

[0578] 2. Computing the preamble: Once the wireless device has a preamble index, it needs to generate the actual signal. The preamble is based on a Zadoff-Chu sequence, a complex-valued mathematical sequence used in LTE (and similarly in 5G). These sequences have two key properties: (1) Constant Amplitude: Ensures uniform signal strength; and (2) Zero Autocorrelation for Non-Zero Lags. In LTE, the sequence length is 839 (denoted as N_ZC=839) for the standard preamble format. Each cell uses one or more root sequences, identified by a root index (e.g., u). The root sequence is the base Zadoff-Chu sequence. From a single root sequence, multiple preambles can be generated by applying cyclic shifts. A cyclic shift is like sliding the sequence in time by a certain number of steps. The size of the shift, N_CS, is determined by the zeroCorrelationZoneConfig parameter, e.g., from a SIB. It ensures preambles are distinct and detectable. A number of preambles, e.g., 64 preambles, indices are mapped to combinations of root sequences and cyclic shifts. For example, if N_CS allows 10 shifts per root sequence, one root sequence provides 10 preambles. To reach 64, the cell uses multiple root sequences (e.g., 7 roots might cover all 64). The UE calculates which root sequence and shift correspond to its chosen index (e.g., index 42 might be the 2nd shift of the 5th root sequence). Mathematically, for a root Zadoff-Chu sequence X_u(n), the preamble with shift v is: X_u((n+v*N_CS) mod N_ZC) where n=0,1,..., N_ZC-1. V represents the number times a cyclic shift increment (N_CS). In general, v = 0, 1, 2,..., floor(N_ZC, N_CS) - 1.

[0579] 3. Transmitting the preamble: The preamble is transmitted in a Random Access Channel (RACH) opportunity, e.g., a specific time-frequency resource allocated for random access. The raw Zadoff-Chu sequence is not sent alone. It is packaged into a specific format, like LTE’s Format 0, which lasts 1 millisecond and includes: (1) A cyclic prefix (to handle timing misalignment); (2) The Zadoff-Chu sequence itself; (3) A guard time (to prevent overlap with other signals). This structure ensures the signal survives real-world issues like multipath fading. Further, The UE calculates the transmission power (power control) based on (1) estimated path loss from downlink signals and (2) Preamble initial received target power indicated by the access device. If the access device does not respond (e.g., due to a collision or weak signal), the wireless device increases the power and retransmits in a later RACH slot, up to a maximum number of attempts. The wireless device modulates the preamble onto the uplink waveform and transmits it in the chosen RACH opportunity. The wireless device listens for these signals, detects the preamble, and responds to proceed with the connection process.

[0580] In a first approach, a wireless device can transmit a second message (e.g., a preamble) in N different slots (e.g., RACH slots) selected at random, and each message indicates which other slots2025PF00195

[0581] 57 23.03.2026

[0582] were used to transmit the message. This approach, optionally combined with a Successive Interference Cancellation (SIC) receiver, increases the chances of successful transmission.

[0583] In a second approach, a wireless device may transmit a second message in N (well-known) slots and / or through B beams to increase the chances of reaching the access device. The access device can use the multiple repetitions of the second message at the well-known slots to improve the reception quality, and thus, increase the coverage.

[0584] It is however challenging to improve both coverage and increase the number of supported wireless devices. This invention aims at tackling this issue.

[0585] The invention proposes the use of a codebook to determine codewords that can facilitate both massive random access and coverage enhancements, e.g., when transmitting uplink traffic. This can be interpreted in such a manner that a codeword can facilitate massive random access or coverage enhancements. In general, " massive random access with enhanced coverage” can be interpreted as a method for massive random access with enhanced coverage during initial access or when performing an uplink transmission. Massive random access is facilitated by (1) increasing the chances at least one of the transmissions (of a second message, e.g., preamble) can go through and (2) supporting the usage of several second messages, e.g., one or more preambles and / or a longer preamble. Coverage is enhanced by (3) using codewords that facilitate repetition and / or multiple transmission of second messages, e.g., preambles and / or parts of a long of a preamble or uplink data messages. A key feature of the invention is that the codewords that may represent transmission opportunities may share some common transmission opportunities. When codewords selected by wireless devices do not overlap (e.g. because there are only a few wireless devices), the coverage enhancement effect is stronger. When codewords selected by wireless devices do overlap (e.g. because there are many wireless devices), coverage enhancement because the proposed constructions ensure that codewords have at least a minimum of non-overlapping transmission occasions. Finally, the usage of a codebook to identify the codewords facilitates determining which transmission occasions are used by a wireless device, improving massive access, e.g., during random access or when transmitting uplink messages.

[0586] In an embodiment of the invention — allowing a wireless device to perform resilient and massive random access to the network — that may be combined with other embodiments or used independently, a wireless device may determine a first random-access codebook (in general access codebook), wherein the first random -access codebook comprises M codewords of length T, the wireless device may select a first codeword from the first random-access codebook; the wireless device may transmit one or more second messages according to the first codeword.

[0587] In general, the random-access codebook or access codebook may comprise codewords, and each codeword may be used to determine transmission occasions for one or more second messages.

[0588] In some examples, the wireless device may be a cellular device such as a 5G UE or a 6G device.2025PF00195

[0589] 58 23.03.2026

[0590] In some examples, the random-access codebook is a first configuration that determines the codewords that can be used by wireless devices to access the network.

[0591] In some examples, the wireless device may receive an indication of the codebook or the codebook itself in a first configuration. In some examples, the one or more second messages are copies of each other. For instance, all second messages are the same preamble (Zadoff-Chu sequence). For instance, a same data message may be transmitted.

[0592] In some examples, the one or more second messages have a common part, and an individual part. For instance, an identifier indicating the selected codeword (e.g., a preamble may act as identifier) and a data field whose content may change in different second messages.

[0593] In some examples, the one or more second messages are different preambles (e.g., Zadoff-Chu sequences) selected in a random manner.

[0594] In some examples, the one or more second messages are different preambles (e.g., Zadoff-Chu sequences) selected according to the codebook. For instance, the codebook may determine which preambles are transmitted in which transmit occasions.

[0595] In some examples, the one or more second messages are fragments of a long second message (e.g., fragments of a long preamble).

[0596] In some examples, the one or more second messages are selected in a consecutive manner from the set of available second messages (e.g., available preambles in a cell) so that they can be linked easily, in other terms, the access device can easily determine that they are part of the same codeword.

[0597] In some examples, the one or more second messages are selected according to a preconfigured pattern (e.g., defined in a codebook or by means of an equation) from the set of available second messages (e.g., available preambles in a cell) so that they can be linked easily.

[0598] In some examples, the selection of the first codeword may be performed by selecting one of the codewords - e.g., of certain parameters in the first random-access codebook at random.

[0599] In some examples, the one or more second messages are simple modifications of the same message, e.g., multiple circular shifts of the same root sequence.

[0600] In some examples, the second message may be an uplink data transmission wherein the intention of the wireless device is to transmit the uplink data transmission to the access device.

[0601] It is to be noted that the second messages in the previous and other (e.g., below) embodiments are not just simple repetitions of the same message, while in other embodiments (e.g., above) the second messages are mainly repetitions of the same message.

[0602] In an embodiment of the invention that may be combined with other embodiments or used independently, the wireless device may receive an indication of the codebook or the codebook itself in a first configuration. The first configuration may be transmitted by means of a message, e.g., an RRC message, or a SIB message, or a DCI message, etc that may determine the codebook to be used. For instance, the RRC message may be received by the wireless device that is connected to an access device. The wireless device may then use the codebook to determine transmit (or transmission) occasions to2025PF00195

[0603] 59 23.03.2026

[0604] transmit one or more second messages according to a codeword in the codebook. The codebook may be used to transmit one or more messages towards the same access device (from which it got the codebook) or towards another access device.

[0605] In an example, this may be applicable, e.g., during cell re-selection wherein the codebook is used to perform the cell re-selection and access a target cell, e.g., transmitting one or more second messages / preambles according to the codework in the physical random access channel.

[0606] In an example, this may be applicable, e.g., during handover wherein the codebook is used to perform the mobility procedure to a target access device.

[0607] In an example, this may be applicable, e.g., in carrier aggregation wherein the codebook is used to access and / or transmit to a secondary cell.

[0608] In an example, this may be applicable, e.g., when performing an uplink control data transmission wherein the codebook is used to transmit the control data, e.g., by transmitting one or more second messages (carrying the control data to be transmitted) in the physical uplink control channel, e.g., uplink control information (UCI) or uplink reference signals such as sounding reference signals.

[0609] In an example, this may be applicable, e.g., when performing an uplink data transmission wherein the codebook is used to perform an uplink data transmission, e.g., by transmitting one or more second messages (carrying the data to be transmitted) in the physical uplink shared channel.

[0610] In an embodiment of the invention — allowing a wireless device to perform resilient and massive random access to the network — that may be combined with other embodiments or used independently,

[0611] - an access device may transmit a first message, e.g., a broadcast message or a unicast message, wherein the first message is adapted to provide one or more wireless devices with a randomaccess configuration, e.g., a codebook configuration and / or a configuration to determine a codeword of a codebook (this configuration may be the first configuration),

[0612] - the access device may receive one or more second messages from at least a first wireless device, and the access device may determine the codeword and / or the one or more second messages transmitted according to the codeword, and

[0613] - the access device may determine transmission resources and / or parameters to transmit a third message, e.g., response message, e.g., a random-access response message based on the determined codebook and / or second messages,

[0614] - and the access device may transmit the third message using the determined transmission resources and / or parameters.

[0615] In an example, the first message may be an RRC message, a SIB message, a MAC CE, or DCI message.

[0616] In an example, the access device may need to perform blind decoding to identify the codewords used during a random -access procedure when receiving the second messages.2025PF00195

[0617] 60 23.03.2026

[0618] In an example, the access device may decode at least a first second message in a transmission occasion, and the first second message may encode the codeword identifier, so that the access device can determine other transmissions occasions used to transmit the remaining of the second messages.

[0619] In an example, the access device may determine the codeword based on the second messages received in the different transmit occasions. This can allow identifying the wireless device sending the one or more second messages. This can allow receiving data encoded in the one or more second messages. For instance, each second messages may comprise a preamble followed by a small data packet and the second messages may be included in T transmit occasions out of N. The wireless device may have been assigned a codeword identifying the one or more preambles and the transmit occasions. This combination of preambles and transmit occasions identify the (codeword assigned to the wireless device. The data appended to the preamble in the second messages is the data that the wireless device needs to transmit.

[0620] In a related embodiment of the invention that may be combined with other embodiments or used independently,

[0621] - the first codeword may identify N transmit occasions (e.g., RACH occasions) out of T possible transmit occasions (e.g., RACH occasions) and / or

[0622] - the first codeword may have Hamming weight N.

[0623] In a related embodiment of the invention that may be combined with other embodiments or used independently, the Hamming distance between any two distinct codewords in the first randomaccess codebook is at least K.

[0624] In some examples, two sequences of transmit occasions from the first random-access codebook may have at least K non-overlapping transmit occasions.

[0625] In an example, the two or more sequences may form a Latin Rectangle. A Latin rectangle is a combinatorial structure that generalizes the concept of a Latin square. A Latin square is an T x T array filled with T different symbols, each occurring exactly once in each row and exactly once in each column. A Latin rectangle, on the other hand, is an M x T array (where M < T), filled with T different symbols such that each symbol appears at most once in each row and at most once in each column. The structure of Latin rectangles makes them a valuable tool in various fields such as design theory, errorcorrecting codes, and scheduling problems. The primary characteristic that differentiates a Latin rectangle from a Latin square is its rectangular shape and the constraint that each symbol does not necessarily need to appear in every row and column — only at most once per row and column. Constructing a Latin rectangle involves arranging symbols in such a way that the constraints are satisfied. For example, consider a 3 x 5 Latin rectangle filled with the symbols 1, 2, 3, 4, and 5. An arrangement could look like this:

[0626] 1 2 3 4 52025PF00195

[0627] 61 23.03.2026

[0628] 23 45 1

[0629] 3 4 5 1 2

[0630] In the above concrete example, each column may correspond to a codeword, and the entries may indicate which of the 5 transmission occasions is used when the codeword is selected. For instance, the first column contains (1,2,3) indicating that the first three transmission occasions are used.

[0631] In an example, the first random-access codebook is a binary constant weight code with word length T, code weight N and minimum Hamming distance K.

[0632] For example, a codebook with M codewords may be represented as a TxM matrix C with 0,1 entries, where a device employing codeword) uses as transmit opportunities the indices i for which C(i,j)=1. For example, we can choose the 7x5 matrix with columns (100011)AT,

[0633] (010101)AT,(001110)AT, (111000)AT, (100100)AT, whereAT denotes “taking the transpose” So there are T=7 transmit opportunities; the codebook has 5 words. The leftmost four codewords correspond to using three transmit opportunities; the rightmost codeword corresponds to using two transmit opportunities. No column has all its ones in the positions of the ones of another vector. As a result, if two devices use the transmit opportunities for transmitting their messages, no message collision occurs, provided that the two devices selected different codewords.

[0634] In an example, any M distinct code words form an TxM matrix comprising an MxM submatrix in which each row and each column contains exactly one T. This guarantees that all messages get through if at most m devices are active and each of them selects and / or is assigned a different entry. An example is a binary constant weight code with code word weight N and minimum Hamming distance equal to 2N-2, so that any two codewords share at most one common transmit opportunity. For example, the weight N=3 codewords of a Hamming code of length 15 (which by definition has minimum Hamming distance K=3) form a codebook of 35 codewords with the property that for any three devices selecting distinct codewords, each device has a transmit opportunity in which it is the only transmitting device. More generally, the Hamming code of length T has T(T-l) / 6 words of weight three and thus gives rise to a codebook with T(T-l) / 6 words, any three distinct codewords allow retrieval of three transmitted messages.

[0635] In an embodiment with K=2, thew codewords are linear combinations, using the bitwise exclusive-OR as addition, of one or more basis words. There are T-l basis words, where each basis word is a binary vector of length T, where T > 2. The basis vectors are labeled 0 through T-2, and the positions within a vector are labeled 0 through T-l, and P (for parity). The basis vector with label k has a one in the position labeled k and in the position P, and zeros in the T-2 other positions. The codeword that is the addition of the basis words with labels kl...kn is assigned the codeword label 2Akl+...+2Akn. For example, when T=4 the basis words are given in the following table. For example, when T=4 the basis words are given in the following table.2025PF00195

[0636] 62 23.03.2026

[0637] Label position \

[0638] 0 1 2 p basis word

[0639] 0 1 0 0 1

[0640] 1 0 1 0 1

[0641] 2 0 0 1 1

[0642]

[0643] The codewords, with their respective codeword labels are then as follows:

[0644] 1 1001

[0645] 2 0101

[0646] 3 1100

[0647] 4 0011

[0648] 5 1010

[0649] 6 0110

[0650] 7 1111

[0651]

[0652] Codewords 1 through 6 have Hamming weight N=2, codeword 7 has Hamming weight 4. The function to generate the codeword for this particular codebook is F(i, N, T=4) = (bO, bl, b2, b3) where i = bO + 2*bl + 4*b2 and b3 = bO + bl+ b2 mod 2, 1 <= i <=7 and N=4 if i=7 and N=2 otherwise.

[0653] In an exemplary embodiment with K=3, the codewords are linear combinations of one or more basis words. Linear combinations may be done using the bitwise exclusive-or (XOR) as addition. In an example, a basis word with label k comprises two parts: one part consists of all zero bits, except for a one bit in the position with position label k, the other part consists of bits that form a binary representation of the number k. The codeword that is the addition of the basis words with labels kl...kn is assigned the codeword label 2kAl+... +2Akn. The basis word labels are chosen such that the binary representation of each basis word label k has at least 2 ones, so that the Hamming weight of the corresponding basis word is at least 3. This implies that the minimum distance of the resulting codebook is at least K. The Hamming weight N of the codeword with label c is equal to the number of ones in the binary representation of c plus the number of ones in the result of the addition of parity bits of the basis words that comprise the codeword. The codebook consists of the codewords with one or more prescribed values of N. Choosing a subset of all possible codewords may increase the minimum distance to a value greater than 3. For example, this construction can be used to generate a codebook in which all codewords have Hamming weight N=5 and the minimum distance K=4. Let the basis word labels be 4-bit numbers. The 11 basis word labels are 3, 5, 6, 7, 9, 10, 11, 12, 13, 14, 15 and the basis words are given in the following table, where the top rows contain the position and parity labels and their reduced values, and the leftmost column contains the basis word labels and its reduced values. Basis word labels 0, 1, 2, 4, and 8 do not occur, because the number of ones in their binary representations is less than 2. The2025PF00195

[0654] 63 23.03.2026

[0655] codeword with label 1096 = 2A3 + 2A6+2A10 is then 10100100001111 and has Hamming weight N=7. We can define the reduced base word and position words by enumerating the occurring base word labels: 3 -> 0, 5 -> 1, 6 -> 2, 7 -> 3, 9 -> 4, 10 -> 5, 11 -> 6, 12 -> 7, 13 -> 8, 14 -> 9,15 -> 10, and the corresponding code word label by replacing the base word labels in the exponents by the reduced base word labels. The codeword with label 1096 then gets reduced codeword label 2A0 + 2A2 + 2A5 = 37. The number of codewords that can be obtained by means of this approach equals two to the power of the number of labels or the number of reduced labels. In this case, there are 11 reduced labels, and thus, the total number of codewords is 2048.

[0656] Reduced

[0657] label 0 1 2 3 4 5 6 7 8 9 10 ParO Pari Par2 Par3 Reduced

[0658] Label

[0659] label 3 5 6 7 9 10 11 12 13 14 15 ParO Pari Par2 Par3 0 3 1 0 0 0 0 0 0 0 0 0 0 1 1 0 0 1 5 0 1 0 0 0 0 0 0 0 0 0 1 0 1 0 2 6 0 0 1 0 0 0 0 0 0 0 0 0 1 1 0 3 7 0 0 0 1 0 0 0 0 0 0 0 1 1 1 0 4 9 0 0 0 0 1 0 0 0 0 0 0 1 0 0 1 5 10 0 0 0 0 0 1 0 0 0 0 0 0 1 0 1 6 11 0 0 0 0 0 0 1 0 0 0 0 1 1 0 1 7 12 0 0 0 0 0 0 0 1 0 0 0 0 0 1 1 8 13 0 0 0 0 0 0 0 0 1 0 0 1 0 1 1 9 14 0 0 0 0 0 0 0 0 0 1 0 0 1 1 1

[0660]

[0661] 10 15 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1

[0662] In this example, the codebook may also be chosen as the set of all codewords with Hamming weight N=5. This gives the following codebook with 168 codewords, together with their reduced labels:

[0663] Red.

[0664] Red. Red. Red.

[0665] codeword codeword Label codeword codeword Label Label Label

[0666] 10101000000001 01101000000010 00011000000011 11011000000000 21 1 22 1 24 1 27 1

[0667] 11000100000001 01100100000100 00010100000101 10110100000000 35 38 40 45

[0668] 1 1 1 1 01001100000011 00101100000101 01011100000100 00111100000010 50 52 58 60

[0669] 0 0 0 0

[0670] 66 01000010000011 68 00100010000101 74 01010010000100 76 00110010000010 1 1 1 1 11001010000001 01101010000100 00011010000101 10111010000000 83 86 88 93

[0671] 0 0 0 0 10100110000001 01100110000010 00010110000011 11010110000000 101 102 104 107

[0672] 0 0 0 0 11000001000010 10100001000100 00010001000110 01110001000000 131 133 136 142

[0673] 1 1 1 1 10001001000011 00101001000110 10011001000100 00111001000001 145 148 153 156

[0674] 0 0 0 0 10000101000101 01000101000110 10010101000010 01010101000001 161 162 169 170

[0675]

[0676] 0 0 0 02025PF00195

[0677] 64 23.03.2026

[0678] 00011101000000 00000011000111 11000011000100 10100011000010 184 192 195 197

[0679] 1 0 0 0 01100011000001 00101011000000 01000111000000 00001111000001 198 212 226 240

[0680] 0 1 1 0 10000000100011 00100000100110 10010000100100 00110000100001 257 1 260 1 265 1 268 1

[0681] 11001000100010 10101000100100 00011000100110 01111000100000 275 277 280 286

[0682] 0 0 0 0 00000100100111 11000100100100 10100100100010 01100100100001 288 291 293 294

[0683] 0 0 0 0

[0684] 308 00101100100000 321 10000010100101 322 01000010100110 329 10010010100010 1 0 0 0 01010010100001 00011010100000 00000110100001 01001110100000 330 344 352 370

[0685] 0 1 1 0 10100001100001 01100001100010 00010001100011 11010001100000 389 390 392 395

[0686] 0 0 0 0 10000101100000 00001101100010 00000011100010 10001011100000 417 432 448 465

[0687] 1 0 1 0 10000000010101 01000000010110 10010000010010 01010000010001 513 514 521 522

[0688] 1 1 1 1 00001000010111 11001000010100 10101000010010 01101000010001 528 0 531 0 533 0 534 0

[0689] 11000100010010 10100100010100 00010100010110 01110100010000 547 549 552 558

[0690] 0 0 0 0 01001100010000 10000010010011 00100010010110 10010010010100 562 577 580 585

[0691] 1 0 0 0 00110010010001 00001010010001 00010110010000 00101110010000 588 0 592 1 616 1 628 0

[0692] 11000001010001 01100001010100 00010001010101 10110001010000 643 646 648 653

[0693] 0 0 0 0 10001001010000 00001101010100 00000011010100 10000111010000 657 688 704 737

[0694] 1 0 1 0

[0695] 770 01000000110011 772 00100000110101 778 01010000110100 780 00110000110010 0 0 0 0 00001000110010 00000100110100 00001010110100 00000110110010 784 800 848 864

[0696] 1 1 0 0 00010001110000 00101001110000 01000101110000 00000011110001 904 916 930 960

[0697] 1 0 0 0 00000000001111 11000000001100 10100000001010 01100000001001 1024 1027 1029 1030

[0698] 1 1 1 1 10001000001101 01001000001110 10011000001010 01011000001001 1041 1042 1049 1050

[0699] 0 0 0 0 10000100001011 00100100001110 10010100001100 00110100001001 1057 0 1060 0 1065 0 1068 0 00001100001001 11000010001010 10100010001100 00010010001110 1072 1091 1093 1096

[0700] 1 0 0 0 01110010001000 01001010001000 00100110001000 00011110001000 1102 1106 1124 1144

[0701] 0 1 1 0 01000001001011 00100001001101 01010001001100 00110001001010 1154 0 1156 0 1162 0 1164 0 00001001001010 00000101001100 00001011001100 00000111001010 1168 1184 1232 1248

[0702] 1 1 0 0 11000000101001 01100000101100 00010000101101 10110000101000 1283 1286 1288 1293

[0703] 0 0 0 0

[0704] 1297 10001000101000 1328 00001100101100 1344 00000010101100 1377 10000110101000 1 0 1 0 00100001101000 00011001101000 00000101101001 01000011101000 1412 1432 1440 1474

[0705] 1 0 0 0 10100000011001 01100000011010 00010000011011 11010000011000 1541 1542 1544 1547

[0706] 0 0 0 0 10000100011000 00001100011010 00000010011010 10001010011000 1569 1584 1600 1617

[0707]

[0708] 1 0 1 02025PF00195

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[0710] 01000001011000 00001001011001 00010101011000 00100011011000 1666 1680 1704 1732

[0711] 1 0 0 0 00000000111001 01001000111000 00100100111000 00010010111000 1792 1810 1828 1864

[0712]

[0713] 1 0 0 0

[0714] It turns out that the minimal distance for this codebook is K=4: since in this example all codewords have the same weight, the minimum distance must be even, so it cannot be 3.

[0715] In an embodiment, a codeword is computed given an index i, a codeword Hamming weight N and a codeword length T = 2Ap - 1 where p is at least 3, using the function F given by

[0716] F(i, N, T=2Ap-l) = (X(N, p, i) * A(N, p)) mod 2

[0717] where

[0718] • A(N, p) is a matrix of size (2Ap-p-l) x (2Ap-l),

[0719] • the k-th row of A(N, p) has zeros in the first 2Ap - p - 1 positions, except for a 1 in position k, • the bits in positions 2Ap - p,...2Ap - 1 satisfy s(k, p) = sum( 2A(j-l) A(N, T)_{k, T - p + j }, j=l,...p), for each k=l,...,2Ap-p-l,

[0720] • X(N, p, i) is the binary row vector (xl, x2,... ) of length 2Ap-p-l with

[0721] sum(2A{j-l) xj,j =1,..., 2Ap-p-l) = r(N, p, i)

[0722] and [r(N,p,l), r(N,p,2),...,r(N, p, S(N, p))] is an array of integers z for which (Z(z) * A(N, p)) mod 2 has Hamming weight N, where Z(z) is the binary row vector of length 2Ap-p-l such that z = sum(2A{j-l} Z(z)J, j=l,..,2Ap-p-l).

[0723] In a related embodiment of the invention that may be combined with other embodiments or used independently, only a subset of the codewords (that can be generated by means of a function, e.g., F(i)) may be selected. For instance, codewords may be selected based on the Hamming weight (e.g., value N) so that only low weight codewords are selected. The available codewords may be indicated to the wireless devices by the access device so that the access device only needs to monitor the indicated subset.

[0724] In an embodiment with minimum distance at least K+l, the basis codewords are constructed from a codebook with minimum distance K, comprising S codewords of length T. The S basis codewords have length S+T. The matrix of basis codewords is the horizontal concatenation of the SxS identity matrix and the SxT codebook matrix. In an example: take the codebook with K=4 and N=5 from the previous example. This first codebook has S= 168 codewords of length T=15. This construction gives a new codebook with up to 2168-1 non-zero codewords. The minimum distance of the new codebook is 6, since each basis vector has Hamming weight 5 + 1 = 6, at least 2 basis vectors must be added to get 4 non-zero parity bits since the minimum distance of the first codebook is 4, and if it is possible to make a linear combination that gives 3 non-zero parity bits it must consist of at least 3 basis vectors. No2025PF00195

[0725] 66 23.03.2026

[0726] combination of the basis vectors has less than 3 non-zero parity bits, since the first codebook is a subset of a complete (except for the all-zero codeword) linear codebook with minimum distance 3.

[0727] In a related embodiment of the invention that may be combined with other embodiments or used independently, the wireless device may receive an indication of N and / or T and / or K from a first access device; and the wireless device may use the indication to determine the first random-access codebook and / or the first codeword.

[0728] In an example, an access device may indicate the parameters in a SIB.

[0729] In an example, an access device may provide the wireless device with the parameters in an RRC message.

[0730] In an example, the wireless device may select codewords of increasing length (T), Hamming weight (N), and Hamming distance (K) for enhanced coverage and / or enhance massive access, wherein the parameters to select may be indicated by the access device, and may be adapted depending on, e.g., the number of retransmissions.

[0731] In a related embodiment of the invention that may be combined with other embodiments or used independently, the wireless device may receive a first signal (or fourth message) (e.g., a system information block and / or synchronization signals and / or a reference signal and / or an RRC message) from a second access device,

[0732] the wireless device may determine one or more features of the first signal (or fourth message), and

[0733] and the wireless device may determine the first random-access codebook and / or the first codeword based on the one or more features of the first signal (or fourth message).

[0734] In an example, the one or more features determined from the first signal (or fourth message) may comprise at least one of:

[0735] - the signal strength of the first signal (or fourth message);

[0736] - the signal quality of the first signal (or fourth message);

[0737] - the type of second access device;

[0738] - the number of wireless devices attempting to perform random-access;

[0739] In an example, a higher N value may be selected when the signal strength of the first signal (or fourth message) is below a first threshold, and / or the first signal (or fourth message) quality is below a second threshold, and / or the distance to the second access device is higher than a third threshold. This example illustrates that when the transmission conditions are worse, the N value increases.

[0740] In an example, a higher K value may be selected when the signal strength of the first signal (or fourth message) is below a fourth threshold, and / or the signal quality of the first signal (or fourth message) is below a fifth threshold, and / or the distance to the second access device is higher than a sixth threshold;. This example illustrates that when the transmission conditions are worse, the N value increases.2025PF00195

[0741] 67 23.03.2026

[0742] In some examples, previous examples may be combined, for instance, when the transmission conditions get worse, then both N and K increase to improve the reliability of the system.

[0743] In an example, when N increases, a higher value of T may also be required.

[0744] In an example, when K increases, a higher value of N may be required.

[0745] In a related embodiment of the invention that may be combined with other embodiments or used independently, the first random-access codebook may be received from a third access device and / or a core network function. This may be received as a first configuration. This may allow performing a random-access procedure or an uplink transmission towards an access device in an efficient manner.

[0746] For instance, it may be configured depending on the location of the wireless device, the type of access required (e.g., terrestrial vs non-terrestrial).

[0747] In some examples, the first random-access codebook may be determined from a preconfigured list or set of codebooks and the determined first random-access codebook is identified by means of a codebook index. For instance, a set of codebooks may be configured, each codebook of different properties, e.g., depending on the number of devices that are seeking access (since this influences T, N, K), the coverage requirements since this influences (K). Depending on the measurements performed by the wireless device, the type of service required by the wireless device, and / or the indications received by the wireless device, the wireless device will select / determine one of the codebooks as the first random-access codebook, and determine from it its first codeword. In some examples, a wireless device may not succeed in a first random access procedure and may adapt the parameters by selecting a different codebook.

[0748] In a related embodiment of the invention that may be combined with other embodiments or used independently, the T transmission occasions may be one of or a combination of:

[0749] - distinct time slots;

[0750] - distinct non-overlapping frequency sub-bands;

[0751] - distinct non-overlapping frequency sub-bands in a single equal timeslot, since it enables ‘quick’ recovery, maybe less energy usage because of not switching on and off;

[0752] - distinct non-overlapping blocks in the time-frequency plane;

[0753] - distinct transmit occasions in different beams;

[0754] - distinct transmit occasions associated to different geographical locations.

[0755] It is to be noted that in this and other embodiments of the invention, a transmit occasion can also be considered / named in a different manner, e.g., communication resources, as used in embodiments of the invention. In some embodiment, transmit occasion may be named transmission occasion. In general, a transmit occasion refers to communication resources used in the transmission of an uplink message.

[0756] In a related embodiment of the invention that may be combined with other embodiments or used independently, some (e.g., N) of the T transmission occasions may be selected by the wireless device means of the first codeword. The selected transmission occasions may be mapped to one or more2025PF00195

[0757] 68 23.03.2026

[0758] of timeslots, frequency sub-bands, beams, geographical locations. Mapping can be done by means of function G that takes as input available resources (time, frequency, beams) and codeword, and outputs which transmission occasions are allocated in which available communication resources.

[0759] In an embodiment of the invention that may be combined with other embodiments or used independently, the codebook may be encoded by indicating the non-zero positions of the codewords. For instance, the 16 bit long binary codeword 1000 0001 00000000, where the left bit is the least significant bit may be encoded as [0,7], This encoding requires only 8 bits.

[0760] In an embodiment of the invention that may be combined with other embodiments or used independently, M distinct codewords form an TxM matrix comprising an MxM submatrix in which each row and each column contains exactly one T.

[0761] In an embodiment of the invention that may be combined with other embodiments or used independently, a first random-access codebook may comprise codewords of a first length N and a second length N2. In general, it may comprise codewords of multiple lengths, e.g., lengths between N_min and N_max. A wireless device may select codewords of a given length, e.g., increasing or decreasing length, depending on the communication needs.

[0762] In some examples, a first random-access codebook comprises codewords of a first length N and a second random-access codebook comprises codewords of a second length N2. In general, there may be codebooks of multiple lengths depending on the communication needs.

[0763] In some examples, the codeword selection length and / or the codebook selection may depend on a determined required codeword Hamming weight.

[0764] Similarly, the codewords in a codebook may have different K, T parameters.

[0765] Similarly, there may be codebooks of featured by different K, T parameters.

[0766] In an embodiment of the invention that may be combined with other embodiments or used independently, the determined first random-access codebook and / or the selected first codeword may depend on one or more of:

[0767] (1) the device capabilities of the wireless device. For instance, wireless devices with lower transmission power may select codewords with a higher N / K value. For instance, depending on the capabilities of the wireless device some codebooks may be assigned or allowed or disallowed. For instance, wireless devices with higher transmission power may select codewords with a lower N value;

[0768] (2) the detection of a second wireless device by the wireless device and / or of a transmission by the second wireless device when transmitting the second message. For instance, when a wireless device determines the transmission of the second wireless device, the wireless device may determine which potential codewords (or codebooks) the second wireless device may be using (since it has already determined one transmission). This may allow the wireless device to check whether it is the same codeword and / or there is a better related choice, e.g., a different codebook that allows increasing the chances of transmission.2025PF00195

[0769] 69 23.03.2026

[0770] In an embodiment of the invention that may be combined with other embodiments or used independently, the wireless device may receive a first signal (or first message) from a fourth access device, wherein the first signal (e.g., SIB, RRC message) indicates a transmission chance. The wireless device may transmit the second message according to the first codeword and to this end, the wireless device may determine whether the wireless device can perform the transmission in a first set of communication resources or a second set of communication resources based on the indicated transmission chance.

[0771] For instance, if the number of devices attempting to gain access is low, the access device may distribute a transmission chance of 1. Any wireless device may then perform random access.

[0772] For instance, if the number of devices attempting to gain access is high, the access device may distribute a transmission chance of 0.1. A wireless device may then perform random access in a current random -access procedure if it selects a random number between 0 and 1, and the random number is between 0 and 0.1. Otherwise, it may need to wait for the next random-access procedure.

[0773] For instance, certain parameters of the selected codebook and / or codeword may also depend on the transmission chance. For instance, in the previous chance, if the selected random number is between 0 and 0.1, the wireless device may select more “powerful” codewords, e.g., higher T value or higher N value. In contrast, another wireless device selecting a random number between 0.1 and 1 may need to use less powerful codewords, e.g., with a lower N value.

[0774] In an embodiment of the invention that may be combined with other embodiments or used independently, the wireless device may receive a third message (e.g., a random-access response message) from an access device. The communication resources (e.g., time / frequency) and / or parameters (e.g., radio network temporal identifier) used to transmit / encode / decode the third message may be determined - totally or partially — by one or more of:

[0775] - the first codeword, e.g., the bit sequence indicated by the first codeword. In this case, the access device may need to determine, e.g., each of the transmission occasions used by the wireless device, and derive from it, e.g., the codeword, and use it to, e.g., determine resources / parameters for the third message;

[0776] - the codebook entry of the selected first codeword, for instance, the access device may need to determine the codebook entry (e.g., by checking it in one of the second messages transmitted in one of the transmission occasions) and verifying that the same (or related) second message appears in other related transmission occasions belonging to the same codeword. If this is confirmed, the codebook entry may then be used to determine transmission resources / parameters for the third message;

[0777] - any transmission occasion indicated by the first codeword: in some cases, the access device may not be able to decode all second messages transmitted in all transmission occasions of the codeword. Thus, the access device may select transmission resources / parameters for the third message that depend on one (or several) of the transmission occasions.2025PF00195

[0778] 70 23.03.2026

[0779] It is noted that in legacy procedures, RACH occasion used for transmitting the initial preamble has one-to-one mapping relationship between RACH Occasion and RAR response. However, when multiple second messages (e.g., preambles) are transmitted, e.g., according to the first codeword, and this may imply through different beams, the re source s / parameters used for the transmission of the response message may be selected differently. This is also the case when multiple preambles through different beams are transmitted for coverage enhancements. For instance, the resources / parameters used for the transmission of RAR messages may depend on the first messages / preambles transmitted through, e.g., two beams. The UE may need to monitor multiple resources when waiting to receive the RAR. Depending on which resources are used to transmit the one or more RARs, the UE could also determine how the access device received the preambles.

[0780] In an embodiment of the invention that may be combined with other embodiments or used independently, the transmit occasions may be partitioned into two or more (up to S) disjoint subsets A_l, A_2,..., A_S and codewords may be pairs (a l, a_2,...,a_S) with a_i in A_i.

[0781] In an example, the set of transmit opportunities is partitioned into two disjoint subsets A and B, and codewords are pairs (a,b) with a in A and b in B. For example, A and B may correspond to even and odd-indexed transmit opportunities, respectively. Assume that three distinct codewords (ai,bi) are chosen, and message mi is transmitted in opportunity ai and bi. If all ai are different, then each mi can be retrieved. If all ai are equal, then all bi are different, and each message can be retrieved. The essentially only problematic case is al=a2^a3 and bl=b3^b2. Then m3 can be retrieved from transmit opportunity a3, and m2 can be retrieved from transmit opportunity b2. The knowledge of m2 (m3) from transmit opportunity b2 (a3) can be used to retrieve ml from transmit opportunity al(bl). So with an interference cancellation technique, all three messages can be retrieved. For example, if T=15, and A and B correspond to the even and odd indices, then the codebook has 8x7=56 words, compared to the 35 words of weight 3 in the Hamming code of length 15. In this example, in both selected transmit opportunities, only three bits need to be used for indicating the other transmit opportunity that is used. Another advantage of this embodiment is that each device uses two transmit opportunities instead of three, thus reducing energy consumption. To see why the partitioning was introduced: if three devices use transmit opportunities (1,2), (1,3) and (2,3), respectively, then the transmit opportunities 1,2 and 3 all are used by two devices, and interference cancellation could not apply.

[0782] In an embodiment of the invention that may be combined with other embodiments or used independently, the first random-access codebook may be generated by means of a codebook function, and wherein the selected first codeword is obtained by evaluating the codebook function in an index identifying the selected first codeword.

[0783] For instance, for K=l, the codebook is generated according to function F(i, N, T). For instance, if there are M codebook entries, and each codebook entry identifies N transmission positions out of T possible transmit occasions, entry i can contain N transmission occasions computed by means of a function F(i, N, T).2025PF00195

[0784] 71 23.03.2026

[0785] In a first example, F(i, N, T) can be:

[0786] i (mod T), i+1 (mod T),..., i+N (mod T) with i = 1,..., M, and M<=T.

[0787] This first example of F(i, N, T) resembles an approach to compute the entries of a Latin Rectangle.

[0788] In a second example, F(i, N, T) can be obtained by means of a pseudorandom function (e.g., a hash function) taking as input, i, N, T, and c. c is a counter or a random value could value can be changed in a deterministic manner in case that F(i, Nl, T, cl) = F(i, N2, T,c2) for N1!=N2.

[0789] In an embodiment that may be combined with other embodiments or used independently, for K=2, N>=K, F(i, N, T, K=2) can be:

[0790] 2*i (mod T), 2*i+ 1 (mod T),..., 2*i+N (mod T) with i = 1,..., M, Kand M<=T.

[0791] In general, for any K value, F(i, N, T, K) can be:

[0792] K*i (mod T), K*i+1 (mod T),..., K*i+N (mod T) with i = 1,..., M, Kand M<=T, For instance, this would allow getting the following six code words for K=2, N=3, M=6, and T= 13.

[0793] 0 1 1 1 000 00 00 00

[0794] 00 0 1 1 1 0 00 00 00

[0795] 00 00 0 1 1 1 0 00 00

[0796] 00 00 000 1 1 1 0 00

[0797] 00 00 000 00 1 1 1 0

[0798] 1 0 00 000 00 00 1 1

[0799] In an embodiment of the invention that may be combined with other embodiments or used independently, the first access device, the second access device, the third access device, and the fourth access device are the same, two, three or fourth different access devices.

[0800] In some examples and technologies, a wireless device may send two or more messages to gain access to the network, wherein the transmission occasions of the two or more messages may be selected at random. To facilitate the reception, each message transmitted in a transmission occasion includes the transmission occasion index used to transmit the other messages. This approach may be however inefficient because if the message is transmitted N times with N>=2, then each message needs to carry N-l identifiers.

[0801] Thus, in an embodiment, a wireless device has a codebook with M entries, and the wireless device can select an entry of the first random-access codebook, i.e., the first codeword, and transmits the second message according to the first codeword in the first random-access codebook entry and includes in the second messages the codebook entry index so that the access device can determine with lower overhead the codeword used, e.g., the transmission occasions to transmit each of the N messages.2025PF00195

[0802] 72 23.03.2026

[0803] In a further example, the wireless device may append to the second message sent in a certain resources (transmission occasions) an identifier for the other resources it used to transmit the message. The access device may, after obtaining the message from a wireless device in a first resource, modify the signals in the other transmit opportunities using the obtained message, and perform decoding on the modified signal(s). For example, if each device chooses two transmit opportunities, it may add to its message sent in a transmit opportunity the index of the other transmit opportunity.

[0804] In an embodiment of the invention that may be combined with other embodiments or used independently, the one or more second messages transmitted according to the first codeword comprises 2, 3,..., N different messages, e.g., preambles. The up to N selected preambles serve as identifier.

[0805] In some examples, the one or more second messages are simple modifications of the same message, e.g., a same preamble, e.g., determined as multiple circular shifts of the same root sequence.

[0806] For instance, if a codeword is 0 1 0 0 1 0 0 1, indicating three transmission occasions (the second, fifth, and eighth) corresponding to bit 1, 4, and 7, a first option is to assign the same second message to the three occasions, e.g., and repeat the very same copy. For instance, if the second message is 0 0 0 0 1 0 0 0, the bit string transmitted would be:

[0807] 0 0 0 0 0 0 0 0

[0808] 0 0 0 0 1 0 0 0

[0809] 0 0 0 0 0 0 0 0

[0810] 0 0 0 0 0 0 0 0

[0811] 0 0 0 0 1 0 0 0

[0812] 0 0 0 0 0 0 0 0

[0813] 0 0 0 0 0 0 0 0

[0814] 0 0 0 0 1 0 0 0

[0815] In a second option, the wireless device transmits three second messages that are small variations of each other. For instance, we can take a root message as before, i.e., 0 0 0 0 1 0 0 0, and the second second message is a cyclic rotation of 2 bits, and the third second message is a further cyclic rotation of 2 bits. In this case, the bit string transmitted would be:

[0816] 0 0 0 0 0 0 0 0

[0817] 0 0 0 0 1 0 0 0

[0818] 0 0 0 0 0 0 0 0

[0819] 0 0 0 0 0 0 0 0

[0820] 0 0 0 0 0 0 1 0

[0821] 0 0 0 0 0 0 0 02025PF00195

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[0823] 0 0 0 0 0 0 0 0

[0824] 1 0 0 0 0 0 0 0

[0825] This embodiment may be advantageous because it may allow multiple devices to select the same codeword. This embodiment may be advantageous because given a set of a few preambles (e.g., 64), more complex multi-dimension preambles can be defined.

[0826] When an access device determines a given second message in a given transmission occasion, the access device may apply a given transformation of the given second message in another related transmission occasion of a codeword, leading to a relatively simple decoding approach.

[0827] In a further embodiment of the invention that may be combined with other embodiments or used independently, the one or more messages may be considered as a long preamble (e.g., a preamble longer than preambles currently used in 4G / 5G) that may be divided into multiple (N) fragments and transmitted according to the first codeword. For instance, if the codeword determines N transmitting occasions, the N fragments of the long preamble may be transmitted in each of the N transmit occasions, e.g., first fragment in the first transmit occasion, second fragment in the second transmit occasion, etc. This embodiment may be advantageous because it may allow increasing the number of available preambles (because of the increased length of the preamble). This approach also provides a solution to link the second messages transmitted in different transmission occasions to each other. For instance, considering that the long preamble is a 24 bit preamble 0 0 0 1 1 0 0 0 0 0 1 0 0 1 0 0 0 1 0 0 0 0 1 0, and the first codeword is 0 1 0 0 1 0 0 1, then the transmitted bitstream is as follows:

[0828] 0 0 0 0 0 0 0 0

[0829] 0 0 0 1 1 0 0 0

[0830] 0 0 0 0 0 0 0 0

[0831] 0 0 0 0 0 0 0 0

[0832] 0 0 1 0 0 1 0 0

[0833] 0 0 0 0 0 0 0 0

[0834] 0 0 0 0 0 0 0 0

[0835] 0 1 0 0 0 0 1 0

[0836] It is to be noted that in some embodiments M is used to indicate the number of beams used when transmitting N second messages, while in some embodiments M is used to determine the number of available codewords. This should be understood according to the different embodiments of the present invention.

[0837] Fig. 20 describes a communication procedure for random access and / or coverage enhancements according to different embodiments of the invention. In Fig. 20 the wireless device is illustrated by means of 2000 and the access device is illustrated by means of 2001. In this figure a single2025PF00195

[0838] 74 23.03.2026

[0839] access device is illustrated, although the functionality may be implemented across a number of access devices (first, second, third and fourth access devices) according to embodiments of the invention. It is to be noted that one or more of the steps described herein may be optional, for instance, steps 2002 and 2003 may be optional.

[0840] In this procedure, an important step is step 2004 in which the wireless device determines the first codeword, wherein the first codeword is one entry of a first random-access codebook; wherein each entry of the first random-access codebook is a codeword to be used by a wireless device to transmit one or more second messages.

[0841] In this procedure, step 2005 represents transmission by the wireless device of one or more second messages according to the first codeword.

[0842] In this procedure, step 2002 represents reception by the wireless device of one or more fourth messages so that the wireless device can perform measurements, and determine the first randomaccess codebook and / or the first codeword based on those measurements.

[0843] In this procedure, step 2003 represents reception by the wireless device of one or more first messages that may comprise a configuration so that the wireless device can obtain a codeword or a codebook to perform the further communication procedure.

[0844] In this procedure, step 2006 represents reception by the wireless device of one or more third messages that may comprise a reply to the one or more transmitted second messages.

[0845] Wireless sensing signal used as an indication signal (FMCW / X-FMCW) In some scenarios, a wireless sensing signal may be re-used as, or embedded into, an indication signal that supports robust detection, time / frequency acquisition and / or resource discovery, without being limited to a legacy PSS / SSS structure. The indication signal may be transmitted in the downlink by an access device (e.g., a base station) to enable a wireless device to reliably detect cell presence, determine a candidate beam, and / or obtain coarse timing and carrier frequency offset (CFO) estimates, while also enabling sensing-related processing (e.g., range / velocity estimation) when desired.

[0846] In a representative example, the indication signal may comprise an FMCW (frequency modulated continuous wave) chirp, i.e., a continuous waveform whose instantaneous frequency sweeps over a configured bandwidth during a configured chirp duration. The chirp may be an up-sweep (increasing frequency versus time), a down-sweep (decreasing frequency versus time), or a combination thereof. In contrast to sequence correlation over many timing and frequency hypotheses, an FMCW-based indication signal can be detected with low complexity by de-chirping (mixing the received signal with a locally generated chirp hypothesis) and observing the resulting beat frequency component. In particular, after de-chirping, energy concentrates around one (or a few) tones in a beat-frequency domain representation, enabling FFT-based detection and enabling simultaneous search across multiple candidate raster frequencies when the receiver front-end bandwidth supports it.

[0847] In some cases, a single-slope FMCW chirp may exhibit a time / frequency ambiguity, e.g., when distinct combinations of timing offset and frequency offset yield similar beat-frequency2025PF00195

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[0849] observations. To improve time / frequency resolution while preserving low-complexity detection, the indication signal may comprise an X-FMCW structure formed by at least two FMCW components having different (e.g., opposite) sweep slopes and overlapping in time. For example, an up-sweep chirp and a down-sweep chirp may be transmitted (partly or fully) overlapping. The receiver may apply separate de-chirp / FFT processing for each sweep direction and jointly estimate timing and CFO from the resulting pair of beat frequencies (e.g., using a sum / difference relationship), thereby improving disambiguation and acquisition robustness.

[0850] More generally, the FMCW / X-FMCW waveform (in general, sensing signal) may serve as an always-on or periodically available indication signal (or acquisition signal) transmitted in known downlink resources and optionally across multiple beams. The indication signal may be used by a receiver to (i) detect presence of a transmitter / cell / beam, (ii) obtain coarse timing and frequency estimates to bootstrap subsequent demodulation, (iii) determine which frequency raster(s) or sub-raster(s) are active, and / or (iv) provide a known probe waveform that supports joint communication-and-sensing functions. The indication signal may be multiplexed with other information (e.g., an identifier, a short payload, or a marker indicating “end of burst”) in time, frequency, and / or by appending / prepending a short data block to the chirp(s).

[0851] Building on previous background, one or more uplink transmissions of one or more second messages are constructed by using one or more sensing signals, e.g., one or more

[0852] FMCW / X-FMCW waveforms. For instance, the one or more “second messages” transmitted by a wireless device comprise one or more chirps. In such embodiments, the uplink FMCW / X-FMCW second message(s) are selected to be easily detectable by an access device (or multiple access devices) using dechirp processing and FFT-based beat-frequency detection, optionally combined with repetition, combining, and / or codebook-based scheduling of transmit occasions as described elsewhere in this disclosure.

[0853] For example, an uplink second message may occupy a configured time-frequency resource (e.g., an uplink shared-channel resource, an uplink control-channel resource, or a dedicated sensing / uplink-indication resource) and may comprise: (i) a single FMCW chirp of duration T and bandwidth B; (ii) an X-FMCW pair (up-sweep and down-sweep); or (iii) a burst of multiple chirps. The access device may apply a local chirp generator matched to candidate slope(s) and candidate raster(s), perform de-chirp and FFT processing over one or more window configurations, and determine presence based on a detected beat-frequency tone exceeding a threshold. This enables low-complexity “energy-on-tone” style detection while still benefiting from the diversity of a wideband waveform. When multiple candidate rasters are covered by a wider receiver bandwidth, multiple raster hypotheses may be tested in parallel.

[0854] In an embodiment of the invention that may be combined with other embodiments or used independently, a wireless device may transmit a plurality of such uplink FMCW / X-FMCW second messages in a plurality of transmission occasions indicated by a codeword of a codebook (e.g., a constant-2025PF00195

[0855] 76 23.03.2026

[0856] weight code). The repetition occasions may be distributed overtime, frequency, and / or beams (e.g., via multiple antenna panels), enabling coverage enhancement and improving the probability that at least one second message is detected. The access device may combine observations from multiple occasions (e.g., non-coherently combining energies in the beat-frequency domain, coherently combining after compensating timing / CFO, or performing majority / CRC -based selection when chirps are associated with short payload blocks). Because FMCW / X-FMCW can be detected via a sparse beat-frequency signature, the access device may monitor many candidate resources with reduced computational burden relative to full sequence correlation, enabling scalability when many wireless devices contend.

[0857] In an embodiment of the invention that may be combined with other embodiments or used independently, to support separation among multiple transmitting wireless devices, the uplink FMCW / X-FMCW second messages may be distinguished by one or more parameters, such as chirp slope, chirp start frequency, chirp duration, cyclic time shift, or an allocated sub-band / sub-raster offset. For example, different “signatures” may be created by allocating different small frequency offsets (subraster spacings) that exceed a maximum expected CFO, so that their beat-frequency observations are separable.

[0858] Additionally or alternatively, the wireless device may transmit an up-sweep / down-sweep pair and the access device may validate candidate detections by checking constraints linking the two beat frequencies (e.g., a bound related to maximum CFO and a constraint related to known raster locations). These mechanisms allow the uplink second messages to remain simple to detect while still enabling identification, grouping, or association of multiple transmissions originating from the same wireless device.

[0859] Accordingly, in later embodiments, one or more second messages may be defined as one or more FMCW / X-FMCW chirps (or chirp bursts) transmitted in the uplink, optionally repeated according to a codeword, and optionally combined with short information blocks. Such second messages may be used as an uplink wake-up signal, an uplink acquisition / indication signal, a preamble-like signal for random access, an uplink wireless sensing signal to allow for the positioning / sensing of the wireless device, or an uplink trigger to enable coordination between a first access device and a second access device. The access device detection may leverage de-chirp processing and beat-frequency domain evaluation to provide robust detection at low complexity, including under large frequency uncertainty and / or when scanning multiple candidate frequency locations.

[0860] In NR, the physical random access channel has multiple “preamble formats” because the physical random access signal has to work across very different deployments: large macro cells with big round-trip delay (RTD), small cells with low delay spread, and FR2 deployments where beam sweeping and low latency dominate. A preamble format is essentially a specific time-domain structure (cyclic prefix length, useful sequence duration, and guard time; and in some cases repetitions / mapping) coupled with a particular PRACH subcarrier spacing and Zadoff-Chu (ZC) sequence length. The first big split is between long and short preambles. Long preambles use a ZC sequence of length 839 and are associated2025PF00195

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[0862] with low PRACH subcarrier spacings (notably 1.25 kHz or 5 kHz). The long symbol time makes them tolerant to large timing uncertainty and large delay spread, so they are the natural choice for large cells (coverage -oriented FR1). Short preambles use a ZC sequence length 139 and are paired with higher PRACH subcarrier spacings (typically aligned with NR numerologies such as 15 / 30 / 60 / 120 kHz). They are much shorter in time, which suits low-latency access and the beam-centric operation common in FR2. Within the long -preamble family (formats 0, 1, 2, 3), the main differences are how the format allocates time to cyclic prefix (CP) and guard time (GT) versus the useful preamble sequence. Increasing CP and / or GT increases robustness to uplink timing uncertainty (e.g., larger cell radius before time alignment) and to channel delay spread, but it costs overhead and reduces how many PRACH opportunities fit in time. So, conceptually, the different long formats are different robustness / overhead trade-offs while keeping the same long sequence length concept. Within the short-preamble family (formats A, B, C with variants like A1 / A2 / A3, B1 / B2 / B3 / B4, C0 / C2), the differences again largely come down to CP and GT sizing and how the preamble is mapped in time for a given numerology. A-formats are generally the “baseline” short formats (lower overhead, lower timing margin), B-formats tend to provide more timing / guard margin (more robust to delay spread / timing error at the expense of more overhead), and C-formats are used for specific guard / timing needs in certain configurations. In practice, the chosen configuration is driven by the deployment’s expected timing uncertainty, delay spread, and whether the system is beam sweeping (where you often prefer shorter occasions you can distribute across beams efficiently).

[0863] In an embodiment of the invention that may be combined with other embodiments or used independently, a preamble for a next generation cellular system may be based on one or more second messages transmitted according to the first codeword, wherein one or more second messages may be based on one more wireless sensing signals, e.g., chirps based on FMCW. This has several advantages:

[0864] - an access device capable of wireless sensing can use its wireless sensing receiver to process such a preamble in an efficient manner;

[0865] - an access device may be able to determine the location / speed of the wireless device more easily;

[0866] Fig. 21 illustrates an example signaling scenario in which a wireless device (2100) and an access device (2101) exchange information using a preamble that is not a conventional fixed sequence, but instead is constructed from wireless sensing signals according to a selected codeword. In the figure, the wireless device (2100) and the access device (2101) communicate over the air interface, and the preamble is formed by transmitting by the wireless device a codeword comprising sensing waveforms (2103) (illustrated as X-FMCW signals) in specific transmission occasions determined by the first codeword. The codeword to be transmitted is determined in step 2102.

[0867] Fig. 22 further illustrates that such a preamble based on a wireless sensing waveform spans a set of T transmission occasions, and that the number of “active” occasions in which a sensing signal is actually transmitted corresponds to the Hamming weight N (i.e., the number of sensing signals2025PF00195

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[0869] transmited). The figure also indicates multiple possible frequency offsets (fO, fl, f2), which are used to differentiate different sensing-signal variants within the preamble construction.

[0870] Fig. 22 explains a possible mapping rule between the codeword and the actual sequence of transmited waveforms over the T transmission occasions. Each transmission occasion is controlled by a 2-bit symbol in the codeword. In the mapping shown, “00” means that no sensing signal is transmited in that occasion, while “01”, “10”, and “11” each indicate transmission of an X-FMCW sensing signal but with different frequency offsets, namely fO, fl, and f2, respectively. In other words, the codeword directly schedules both (i) whether a signal is present in a given occasion and (ii) which of the available frequency-offset variants is used when a signal is present.

[0871] As an example in Fig. 22, the codeword 01000011110001001110 may be interpreted as a sequence of 2-bit control symbols across T = 10 transmission occasions. Reading the codeword in 2-bit chunks yields the per-occasion instructions, where “01” selects X-FMCW at fO, “10” selects X-FMCW at fl, “11” selects X-FMCW at f2, and “00” leaves the occasion empty. The resulting preamble shown in the figure is therefore the time-ordered set of transmission occasions in which the appropriate X-FMCW signals (with offsets fO / fl / f2) are transmited, interspersed with empty occasions. For this specific example, the Hamming weight, which here is to be interpreted as the number of non-zero two-bits blocks, is 6, meaning that 6 out of the 10 occasions carry sensing signals and the remaining 4 occasions are empty.

[0872] In general, this means that the codeword indicates both the transmit occassions comprising a second message, and which second message is transmited in it.

[0873] In another example, the codeword may comprise two parts: 1001101011 and 011111011110. The first part “1001101011” is a bitmap indicating which transmit occasions contain data / a signal. The second part “011111011110” indicates which second signals (in general, which second messages) are transmited in the transmit occasions containing data / a signal. In this specific example, two bits are used for each signal, when there are three possible signals. A more compact representation may be used, e.g., if there are T second messages, and there are R different potential second messages, then there are RTpossible combinations. So that a bitstring of length CEIL(Log2(RT)) may be sufficient.

[0874] A sensing -based, codeword-driven preamble (e.g., built from X-FMCW waveforms scheduled over T transmission occasions with Hamming weight N) provides several benefits versus a traditional 5G NR PRACH preamble (single ZC-based sequence sent in one PRACH occasion). First, it enables coverage and detection robustness via structured repetition and diversity: transmiting the preamble energy across multiple occasions (and potentially different frequency offsets such as fD,fl,f2f_0,f_l,f_2fD,fl,f2 ) increases the probability that at least some components are received with sufficient SNR even under fading, blockage, or high path loss. Second, it can improve massive-access scalability and collision resilience because different users can be assigned / choose different codewords whose paterns are designed to ensure a minimum number of non-overlapping occasions (or minimum Hamming distance), which helps the receiver separate multiple simultaneous contenders beyond the2025PF00195

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[0876] limited orthogonality space of conventional PRACH. Third, it can reduce receiver search complexity in some implementations by allowing energy / FFT-style detection of known FMCW variants (including discrimination via frequency offsets) across the TTT occasions rather than relying solely on large correlation banks. Finally, because the “preamble” is itself a sensing waveform, it can naturally support integrated sensing and communications, enabling the access device to reuse the received signal not only for access detection but also for extracting sensing -related observables (e.g., range / velocity-related information) while preserving the preamble’s role as an access trigger.

[0877] In an embodiment that may be combined with other embodiments or used independently, the sensing signal used to form the one or more second messages (e.g., a preamble) is generalized such that the transmission occasions need not have a fixed duration and / or the sensing signal need not occupy a fixed frequency range. In particular, the wireless device and the access device may be configured with a parameterized family of sensing signals (e.g., FMCW or X-FMCW signals) in which each transmission occasion is associated with one or more waveform parameters, such as a duration (chirp time), an initial frequency, a final frequency, a frequency slope, a swept bandwidth, a phase code, and / or a frequency offset. The random-access codebook may be configured jointly with the parametrized family. The first codeword may then determine, for each of the T transmission occasions, whether no signal is transmitted and / or which sensing-signal parameter set is used in that transmission occasion. For example, a first subset of codeword symbols may select the set of occupied transmission occasions, and a second subset of codeword symbols may select, for each occupied transmission occasion, one of multiple allowable durations and / or one of multiple allowable frequency ranges (e.g., different pairs of initial and final frequencies), optionally subject to constraints configured by the access device (e.g., maximum occupied bandwidth, spectral mask compliance, and / or non-overlap with protected resources). As a result, a substantially larger number of distinct sequences (and thus a substantially larger number of distinct preambles) can be created from the same basic sensing-signal family by jointly varying the occupied occasions and the per-occasion waveform parameters. This embodiment may be advantageous because it increases the signature space available for random access (thereby reducing collision probability under massive access), while also allowing the access device to exploit waveform diversity (time / frequency diversity and / or diversity across chirp slopes / bandwidths).

[0878] In an embodiment that may be combined with other embodiments or used independently, the one or more second messages transmitted according to the first codeword may comprise a combination of wireless sensing signals and traditional sequences such as Zadoff-Chu (ZC) based sequences, m-sequences, gold-sequences. For instance, a wireless device may be configured with a mapping (e.g., as part of the first configuration and / or as part of the random-access codebook definition) that associates each transmission occasion indicated by the first codeword with one of: (i) no transmission, (ii) transmission of a wireless sensing signal, e.g., an X-FMCW chirp with a selected frequency offset, and / or (iii) transmission of a ZC-based sequence (e.g., a PRACH-like preamble sequence or a fragment / variant thereof). In a non-limiting example, the codeword may select a set of N2025PF00195

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[0880] transmission occasions out of T, and the first elements (i.e., earlier selected transmission occasions) may carry no transmission or X-FMCW signals while one or more later selected transmission occasions may carry no transmission or ZC-based sequences, or vice versa. wireless device may have

[0881] In another non-limiting example, the codeword may determine an interleaving pattern in which X-FMCW transmissions and ZC-based transmissions alternate across the selected transmission occasions. This hybrid construction may be advantageous because it combines complementary detection and propagation properties: the sensing-signal component (e.g., X-FMCW) can provide robust coarse detection and / or additional observables (e.g., for timing / frequency disambiguation and / or sensing-related measurements), while the ZC-based component provides strong correlation properties for fine timing acquisition and / or improved separation between multiple contending wireless devices. As a result, the access device may increase the probability of detecting the second message(s) under low-SNR or high-interference conditions, while also improving contention resolution and reducing the likelihood of false detection by leveraging two different waveform families within a single codeword-defined preamble structure.

[0882] Section: miscellaneous

[0883] Section: miscellaneous

[0884] This invention can be applied to various types of UEs or terminal devices, such as mobile phone, vital signs monitoring / telemetry devices, smartwatches, detectors, vehicles (for vehicle-to-vehicle (V2V) communication or more general vehicle-to-everything (V2X) communication), V2X devices, Internet of Things (IoT) hubs, loT devices, including low-power medical sensors for health monitoring, medical (emergency) diagnosis and treatment devices, for hospital use or first-responder use, virtual reality (VR) headsets, etc.

[0885] Fig. 19 is a block diagram illustrating an example processor X00 for use in embodiments of the invention. Processor X00 may be used to implement one or more processors described herein, for example, processor 202 shown in Fig. 2. Processor X00 may include any suitable processor type including, but not limited to, a microprocessor, a microcontroller, a digital signal processor (DSP), a field programmable array (FPGA) where the FPGA has been programmed to form a processor, a graphical processing unit (GPU), an application specific circuit (ASIC) where the ASIC has been designed to form a processor, or a combination thereof.

[0886] The processor X00 may include one or more cores X02. The core X02 may include one or more arithmetic logic units (ALU) X04. In some embodiments, the core X02 may include a floatingpoint logic unit (FPLU) X06 and / or a digital signal processing unit (DSPU) X08 in addition to or instead of the ALU X04.2025PF00195

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[0888] The processor X00 may include one or more registers X12 communicatively coupled to the core X02. The registers X12 may be implemented using dedicated logic gate circuits (e.g., flip-flops) and / or any memory technology. In some embodiments, the registers X12 may be implemented using static memory. The register may provide data, instructions and addresses to the core X02.

[0889] In some embodiments, processor X00 may include one or more levels of cache memory X10 communicatively coupled to the core X02. The cache memory X10 may provide computer-readable instructions to the core X02 for execution. The cache memory X10 may provide data for processing by the core X02. In some embodiments, the computer-readable instructions may have been provided to the cache memory X10 by a local memory, for example, local memory attached to the external bus XI 6. The cache memory X10 may be implemented with any suitable cache memory type, for example, metal -oxide semiconductor (MOS) memory such as static random-access memory (SRAM), dynamic random-access memory (DRAM), and / or any other suitable memory technology.

[0890] The processor X00 may include a controller XI 4, which may control input to the processor X00 from other processors and / or components included in a system and / or outputs from the processor X00 to other processors and / or components included in the system. Controller X14 may control the data paths in the ALU X04, FPLU X06 and / or DSPU X08. Controller X14 may be implemented as one or more state machines, data paths and / or dedicated control logic. The gates of controller X14 may be implemented as standalone gates, FPGA, ASIC or any other suitable technology.

[0891] The registers X12 and the cache X10 may communicate with controller X 14 and core X02 via internal connections X20A, X20B, X20C and X20D. Internal connections may be implemented as a bus, multiplexor, crossbar switch, and / or any other suitable connection technology.

[0892] Inputs and outputs for the processor X00 may be provided via a bus XI 6, which may include one or more conductive lines. The bus X16 may be communicatively coupled to one or more components of processor X00, for example the controller X14, cache X10, and / or register X12. The bus X16 may be coupled to one or more components of the system, such as components BBB and CCC mentioned previously.

[0893] The bus X16 may be coupled to one or more external memories. The external memories may include Read Only Memory (ROM) X32. ROM X32 may be a masked ROM, Electronically Programmable Read Only Memory (EPROM) or any other suitable technology. The external memory may include Random Access Memory (RAM) X33. RAM X33 may be a static RAM, battery backed up static RAM, Dynamic RAM (DRAM) or any other suitable technology. The external memory may include Electrically Erasable Programmable Read Only Memory (EEPROM) X35. The external memory may include Flash memory X34. The external memory may include a magnetic storage device such as disc X36. In some embodiments, the external memories may be included in a system, such as a UE.

[0894] In this disclosure, different embodiments and examples are described illustrating how different techniques in the invention may be used or applied to different use cases or deployments.2025PF00195

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[0896] The invention may be applicable to use cases, deployments, or embodiments beyond the embodiments and examples in the present description.

[0897] Elements, steps, and procedures from the different embodiments or examples may be arranged to create further procedures or embodiments.

[0898] In figures and message flows, one or more steps of a procedure may be re-ordered and / or performed multiple times and / or combined with other procedures.

[0899] In some cases, some steps may not be described for clarity purposes.

[0900] Procedures may involve a configuration step to perform the desired function.

[0901] One or more steps of a procedure may be performed when a condition is met by one or more entities of a wireless system, e.g., a wireless device, and / or an access device, and / or a network function of the core network.

[0902] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure and the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0903] In the claims and in the disclosure, the words “comprising” or “contains” or “consists of’ or “includes” do not exclude other elements or steps or may indicate one or more parts / elements.

[0904] Writing “based on X” indicates that it is “based at least on X”, and it is “not based only on X”. Similarly, “depends on X” indicates that it “depends at least on X”, and it does “depend only on X”. Similarly, writing that something “uses / employs X” indicates that it “uses / employs at least X” and “not only X.

[0905] Writing that a device “is configured” may indicate that the device has been configured (e.g., by another device, configuration, etc) to perform a certain operation according to a configuration.

[0906] Writing that a device receives or obtains a “control message or configuration” may indicate that the “control message or configuration” includes a configuration with a parameter that allows implementing / performing a certain operation in the device.

[0907] In this disclosure, a parameter or value or information element etc may comprise one or more parameters. This may be done in multiple levels or layers. For instance, A may comprise B, and B may comprise C, and C may comprise D.

[0908] In this disclosure, a statement that “one or more parameters” comprises “one or more values” indicates that “a value” in the “one or more values” is at least in “a parameter” of the “one or more parameters”.

[0909] In this disclosure, often optional features are described optional by using “may” or parentheses.

[0910] In this disclosure, certain descriptions, e.g., a procedure related to a figure, or a list of parameters, etc may sometimes be described as a set of steps, or parameters, etc. Those steps or parameters in a description may be considered as optional or illustrative, and may not imply that all steps2025PF00195

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[0912] or parameters are required, or that no other steps or parameters may be used. For instance, a statement that the procedure performs step A, step B, and step C may also be interpreted as the procedure may perform step A, and / or step B, and / or step C. Similarly, a statement that a configuration includes parameter A, parameter B, and parameter C may also be interpreted as the configuration may include parameter A, and / or parameter B, and / or parameter C.

[0913] In the claims and in the disclosure the indefinite article “a” or “an” does not exclude a plurality.

[0914] In the claims and in the disclosures, words written in singular and / or plural may be interpreted as “at least one” and “one or more”.

[0915] In this disclosure, “may” indicates “may, for example”. When a sentence is written using may, it indicates that the following word (e.g., a verb) may be optional.

[0916] In this disclosure, a procedure comprising a number of steps may be considered as a procedure comprising one or more of those steps, even if the description of the procedure does not explicitly indicate the optionality of one or more of the steps; furthermore, steps not mentioned may also be included.

[0917] Writing “X and / or Y” indicates any combination ofX and Y; similarly, if “X, Y, and / or Z” is written, it can mean “X”, ‘Y”, “Z”, “X and Y”, “X and Z”, ‘Y and Z”, and “X, Y, and Z”.

[0918] Additionally, the expression “at least one of A, B, and C” is to be understood as disjunctive, i.e., as “A and / or B and / or C”. The same applies to the expressions “A or B” and “at least one of A or B”, i.e., they may indicate all possible combinations of the listed items.

[0919] In this disclosure, each and every permutation of options may not be described and / or be explicitly described, for the sake of conciseness and clarity. And yet, in this disclosure, the disclosure may be interpreted so as to describe those possible combinations.

[0920] A single processor or other unit may fulfil the functions of several items recited in the claims. Measures recited in mutually different dependent claims may advantageously be combined. The foregoing description details certain embodiments of the invention. It will be appreciated, however, that no matter how detailed the foregoing appears in the text, the invention may be practiced in many ways, and is therefore not limited to the embodiments disclosed. It should be noted that the use of particular terminology when describing certain features or aspects of the invention should not be taken to imply that the terminology is being re-defined herein to be restricted to include any specific characteristics of the features or aspects of the invention with which that terminology is associated.

[0921] The described operations like those indicated in the above embodiments may be implemented as program code of a computer program and / or as dedicated hardware of the related network device or function, respectively. The computer program may be stored and / or distributed on a suitable (non-transitory) computer-readable medium, such as an optical storage medium or a solid-state medium, supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems.

Claims

2025PF0019523.03.2026CLAIMS:

1. A method for massive random access with enhanced coverage, comprising:- determining, by a wireless device, a first codeword, wherein the first codeword is one entry of a first random-access codebook; wherein each entry of the first random-access codebook is a codeword to be used by a wireless device to transmit one or more second messages,- transmitting, by the wireless device, one or more second messages according to the first codeword.

2. The method of claim 1, comprisingdetermining, by the wireless device, the first random-access codebook.

3. The method of claim 2, wherein the determining the first random -access codebook comprises the wireless device receiving an indication of the first codebook in a first configuration.

4. The method of any of the preceding claims, wherein the first codeword identifies N transmit occasions out of T possible transmit occasions.

5. The method of claim 4, wherein- at least two codewords share a common transmit occasion; or- the first codeword shares a common transmit occasion with another codeword.

6. The method of any of the preceding claims, wherein the first codeword has Hamming weight N.

7. The method of claim 6, wherein- at least two codewords of Hamming weight N have Hamming distance K = N-l; or - the first codeword and another codeword have Hamming weight N, and the first codeword and the another codeword have Hamming distance K=N-1.

8. The method of any of claims 4, 5 and 6 and 7 when dependent of claims 4 and 5, wherein any two sequences of transmit occasions from the first random-access codebook have at least K nonoverlapping transmit occasions.2025PF0019585 23.03.20269. The method of any previous claims, wherein the Hamming distance between any two distinct codewords in the first random-access codebook is at least K.

10. The method of any previous claims, wherein the method further comprises:- receiving, by the wireless device, a first message including an indication of N and / or T and / or K from a first access device; and- using, by the wireless device, the indication to determine the first random-access codebook.

11. The method of any previous claims, further comprising:- receiving, by the wireless device, a fourth message from a second access device, - determining, by the wireless device, one or more features of the fourth message, and - determining, by the wireless device, the first random-access codebook and / or the first codeword based on the one or more features of the fourth message.

12. The method of claim 11, wherein the one or more features comprise at least one of:- the signal strength of the fourth message;- the signal quality of the fourth message;- the type of second access device;- the number of wireless devices attempting to perform random -access.

13. The method of claims 11, or 12, wherein:- a higher N value is selected when the signal strength is below a first threshold, and / or the signal quality is below a second threshold, and / or the distance to the second access device is greater than a third threshold; and / or- a higher K value is selected when the signal strength is below a fourth threshold, and / or the signal quality is below a fifth threshold, and / or the distance to the second access device is greater than a sixth threshold.

14. The method of any previous claims, wherein the two or more codewords or sequences of transmit occasions in the first random -access codebook form a Latin rectangle.

15. The method of any previous claims, wherein the first random-access codebook is received from a third access device and / or a core network function.2025PF0019586 23.03.202616. The method of any previous claims, wherein the first random -access codebook is determined from a pre-configured list or set of codebooks and the determined first random-access codebook is identified by means of a codebook index.

17. The method of any of the claims 4 to 16, wherein the T transmission occasions are one of or a combination of:- distinct time slots;- distinct non-overlapping frequency sub-bands;- distinct non-overlapping frequency sub-bands in a single equal timeslot;- distinct non-overlapping blocks in the time-frequency plane;- distinct transmit occasions in different beams;- distinct transmit occasions associated to different geographical locations.

18. The method of any previous claims, wherein the first random -access codebook is a binary constant weight code with word length T, code weight N and minimum Hamming distance K.

19. The method of claim 18, wherein the codebook is encoded by indicating the non-zero positions of the codewords.

20. The method of any previous claims, wherein M distinct codewords form an TxM matrix comprising an MxM submatrix in which each row and each column contains exactly one T.

21. The method any previous claims, wherein- the first random-access codebook comprises codewords of a first length N and a second length N2; or- the first random-access codebook comprises codewords of a first length N and a second random-access codebook comprises codewords of a second length N2and whereinthe codeword selection length and / or the codebook selection depends on a determined required codeword Hamming weight and / or length.

22. The method of any previous claims, wherein the determined first random -access codebook and / or the selected first codeword depend on one or more of:the device capabilities of the wireless device;the detection of a second wireless device by the wireless device;the detection of a transmission by a second wireless device when transmitting the second message.2025PF0019587 23.03.202623. The method of any previous claims, further comprising:- receiving, by the wireless device, a first message from a fourth access device, wherein the first message indicates a transmission chance;and wherein transmitting, by the wireless device, the second message according to the first codeword comprises determining whether the wireless device can perform the transmission in a first set of communication resources or a second set of communication resources based on the indicated transmission chance.

24. The method of any previous claims, comprising:- receiving, by the wireless device, a third message,- wherein the communication resources and / or parameters used to transmit the third message are determined based on one or more of:- the first codeword,- the codebook entry of the selected first codeword,- any transmission occasion indicated by the first codeword; or- one or more transmitted second messages.

25. The method of any claims from 4 to 24, wherein:- transmit occasions are partitioned into two disjoint subsets A and B, and - codewords are pairs (a,b) with a in A and b in B.

26. The method of any of the previous claims, wherein the first random -access codebook is generated by means of a codebook function characterized by one or more of the following features:- the codebook function computes the first codeword by taking as input the index identifying the selected first codeword;- the codebook function computes the first codeword as a linear combination of code basis vectors;- the codebook function takes as input the desired Hamming distance between the first codeword and any other codeword; and- the codebook function takes as input the desired Hamming weight of the codeword.

27. The method of any of the previous claims, wherein the first access device, the second access device, the third access device, and the fourth access device are the same, two, three or fourth different access devices.2025PF0019588 23.03.202628. The method of any of the previous claims 1 to 27, wherein the one or more second messages transmitted according to the first codeword comprises 1, 2, 3,..., N different second messages, and wherein the combination of the 1, 2, 3,..., N second messages and / or codeword serve as identifier of the wireless device attempting to gain network access.

29. The method of any previous claims 1 to 28, wherein each second message transmitted in each transmission occasion encodes the first codeword identifier, and / or the identities of the one or more second messages, and / or a transformation to obtain the one or more second messages.

30. The method of any of the previous claims, wherein the first codeword determines the transmit occasions used in the transmission of the one or more messages and the parameters of the one or more second messages31. The method of any previous claims, wherein a second message comprises a wireless sensing signal, andwherein the first codeword determines the transmit occasions used in the transmission of the one or more messages and the parameters of the one or more second messages32. The method of any of the previous claims 4 to 31, wherein the N second messages transmitted in the T transmit occasions define an uplink preamble or uplink wake-up signal or uplink sounding reference signal.

33. A method for massive random access with enhanced coverage comprising:- transmitting, by an access device, a first message to one or more wireless devices, wherein the first message is used by the one or more wireless devices to determine a first random-access codebook and / or codeword for the transmission of one or more second messages; and- receiving, by the access device, one or more second messages according to a first codeword from at least a first wireless device, and the access device determining the codeword and / or the one or more second messages transmitted according to the codeword.

34. An apparatus for massive random access with enhanced coverage comprising:- a transceiver,- a processor, and- a memory storing instructions which, when executed, cause the apparatus to- determining a first codeword, wherein the first codeword is one entry of a first randomaccess codebook; wherein each entry of the first random-access codebook is a codeword to be used by a wireless device to transmit one or more second messages,2025PF0019589 23.03.2026- transmiting one or more second message according to the first codeword.

35. An apparatus for massive random access with enhanced coverage comprising:- a transceiver,- a processor, and- a memory storing instructions which, when executed, cause the apparatus to- transmit a first message to one or more wireless devices, wherein the first message is used by the one or more wireless devices to determine a first random-access codebook and / or codeword for the transmission of one or more second messages; and- receive one or more second messages according to a first codeword from at least a first wireless device, and- determine the codeword and / or the one or more second messages transmited according to the codeword.

36. A computer program for massive random access with enhanced coverage comprising computer instructions to perform the steps in the methods of any of claims 1 to 33.

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