Flexible carrier bandwidth handling in wireless communication systems

Abstract

Generally, the present subject matter relates to flexible carrier bandwidth processing in wireless communication systems. In some implementations, a first signal in a first fixed operating bandwidth among a plurality of fixed operating bandwidths defined for the cellular network and a second signal in a second fixed operating bandwidth among a plurality of fixed operating bandwidths defined for the cellular network can be received at a first communication device in the cellular network from a second communication device in the cellular network. The first signal and the second signal can have subcarrier overlap, and the first signal and the second signal can each include at least one null subcarrier value and at least one non-null subcarrier value. The first signal and the second signal can be combined into a single signal that does not include the at least one null subcarrier value of the first signal and the second signal.

Description

[Technical Field]

[0001] In some implementations, the present subject matter relates to telecommunications systems, and more particularly to flexible carrier bandwidth handling in wireless communication systems. [Background technology]

[0002] In today's world, cellular networks provide on-demand communication capabilities to individuals and businesses. Typically, cellular networks are wireless networks that can be distributed over a terrestrial area called a cell. Each such cell is served by at least one fixed-location transceiver called a cell site or base station. Each cell may use a different set of frequencies from its neighboring cells to avoid interference and provide improved service within each cell. When cells are combined together, they provide radio coverage over a wide geographic area, allowing numerous mobile phones and / or other wireless devices or portable transceivers to communicate with each other and with fixed transceivers and phones anywhere in the network. Such communication is performed through base stations and is achieved even when the mobile transceiver is traveling through two or more cells during transmission. Major wireless communication providers have deployed such cell sites worldwide, allowing communicating mobile phones and mobile computing devices to connect to the public switched telephone network and the public Internet.

[0003] A mobile phone is a portable telephone that can receive and / or make telephone and / or data communications through a cell site or transmission tower by using radio waves to transfer signals to and from the mobile phone. Given the large number of mobile phone users, current mobile phone networks offer limited shared resources. In that regard, cell sites and handsets can change frequencies and use low-power transmitters to allow simultaneous use of the network by many callers with less interference. Cell site coverage can depend on a particular geographic location and / or the number of users that can potentially use the network. For example, in cities, cell sites may have a range of up to about 1 / 2 mile, while in suburban areas, the range may be as much as 5 miles, and in some areas, users can receive signals from cell sites 25 miles away.

[0004] The following are some examples of digital cellular technologies used by communication providers: Global System for Mobile Communications ("GSM"), General Packet Radio Service ("GPRS"), cdmaOne, CDMA2000, Evolved Data Optimized ("EV-DO"), Enhanced Data Rates for GSM Evolution ("EDGE"), Universal Mobile Telecommunications System ("UMTS"), Digital Enhanced Cordless Communications ("DECT"), Digital AMPS ("IS-136 / TDMA"), and Integrated Digital Enhanced Network ("iDEN"). 4G LTE, developed by the Long Term Evolution, or 3rd Generation Partnership Project ("3GPP®") standards organization, is a standard for high-speed data wireless communication for mobile phones and data terminals. 5G standards are currently being developed and deployed. 3GPP cellular technologies such as LTE and 5G New Radio (“NR”) are an evolution of earlier generations of 3GPP technologies such as GSM / EDGE and UMTS / HSPA digital cellular technologies, and enable increased capacity and speeds by using different air interfaces along with core network improvements.

[0005] A cellular network may be divided into a radio access network and a core network. The radio access network (RAN) may include network functions capable of handling radio layer communication processing. The core network may include network functions capable of handling higher layer communication, such as Internet Protocol (IP), transport layer, and application layer. In some cases, the RAN function may be divided into baseband unit function and radio unit function; for example, a radio unit connected to the baseband unit via a fronthaul network may be responsible for lower layer processing of the radio physical layer, and the baseband unit may be responsible for higher layer radio protocols, such as MAC, RLC, etc.

[0006] LTE wireless communication systems use frequency bands that support channel bandwidths specified in the 3GPP standard (3GPP TS 36.101): 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz, and 20 MHz. 5G NR wireless communication systems also use frequency bands that support channel bandwidths specified in the 3GPP standard (3GPP TS 38.101): 5 MHz, 10 MHz, 15 MHz, 20 MHz, 25 MHz, 30 MHz, 35 MHz, 40 MHz, 45 MHz, 50 MHz, 60 MHz, 70 MHz, 80 MHz, 90 MHz, and 100 MHz. Spectrum bandwidth released from legacy networks (e.g., 2G LTE and 3G LTE) is available for LTE or NR wireless communication systems. However, the released bandwidth may not be within the defined fixed operating channel bandwidths and may therefore be unused, resulting in wasted available resources. Summary of the Invention

[0007] In some implementations, the present subject matter relates to a computer-implemented method. The method may include, at a first communication device in a cellular network, receiving from a second communication device in the cellular network a first signal in a first fixed operating bandwidth of a plurality of fixed operating bandwidths defined for the cellular network and a second signal in a second fixed operating bandwidth of a plurality of fixed operating bandwidths defined for the cellular network. The first signal and the second signal may have subcarrier overlap, where the first signal may include at least one null subcarrier value and at least one non-null subcarrier value, and the second signal may include at least one null subcarrier value and at least one non-null subcarrier value. The method may also include combining the first signal and the second signal into a single signal that does not include the at least one null subcarrier value of the first signal and does not include the at least one null subcarrier value of the second signal.

[0008] In some implementations, the present subject matter can include one or more of the following optional features.

[0009] In some implementations, at least one null subcarrier value of the first signal may follow at least one non-null subcarrier value of the first signal, and at least one null subcarrier value of the second signal may precede at least one non-null subcarrier value of the second signal, and combining the first and second signals into a single signal may include using at least one non-null subcarrier value of the first signal as a leading subcarrier value of the single signal, and using at least one non-null subcarrier value of the second signal as a trailing subcarrier value of the single signal that follows all of the leading subcarrier values.

[0010] In some implementations, an error condition may occur when at least one null subcarrier value of a first signal precedes at least one non-null subcarrier value of the first signal and at least one non-null subcarrier value of a second signal precedes at least one null subcarrier value of the second signal.

[0011] In some implementations, at least one non-null subcarrier value of the first signal may overlap with at least one null subcarrier value of the second signal, and at least one non-null subcarrier value of the second signal may overlap with at least one null subcarrier value of the first signal.

[0012] In some implementations, the method may further include, after combining the first signal and the second signal into a single signal, applying an inverse fast Fourier transform ("IFFT") process or a fast Fourier transform ("FFT") process to the single signal.

[0013] In some implementations, the method may further include applying IFFT or FFT processing to the first signal and applying IFFT or FFT processing to the second signal before combining the first signal and the second signal into a single signal.

[0014] In some implementations, the single signal may reflect a bandwidth that is not one of multiple fixed operating bandwidths defined for the cellular network.

[0015] In some implementations, the method may further include performing a handshake between the first communication device and the second communication device that establishes an understanding that the binding will be performed at a later time.

[0016] In some implementations, the method may further include detecting subcarrier overlap using digital domain IQ data transmitted in the frequency domain of each of the first signal and the second signal and using symbol duration transmitted in the time domain of each of the first signal and the second signal, which detecting can facilitate combining the first signal and the second signal into a single signal.

[0017] In some implementations, one of the first communication device and the second communication device may include a distribution unit, and the other of the first communication device and the second communication device may include a radio unit. Furthermore, the first communication device receiving the first signal and the second signal may include a distribution unit, and the second communication device may include a radio unit such that the communication is uplink communication, or the first communication device receiving the first signal and the second signal may include a radio unit, and the second communication device may include a distribution unit such that the communication is downlink communication. Furthermore, the first communication device may perform the combining.

[0018] In some implementations, the cellular network may be a 3GPP LTE network. Further, the single signal may reflect a bandwidth that is not one of multiple fixed operating bandwidths defined for the network.

[0019] In some implementations, the cellular network may be a 5G network. Further, the single signal may reflect a bandwidth that is not one of multiple fixed operating bandwidths defined for the network.

[0020] In some implementations, the first fixed operating bandwidth of the plurality of fixed operating bandwidths and the second fixed operating bandwidth of the plurality of fixed operating bandwidths may be different from each other.

[0021] In some implementations, the first fixed operating bandwidth of the plurality of fixed operating bandwidths and the second fixed operating bandwidth of the plurality of fixed operating bandwidths may be the same as each other.

[0022] Non-transitory computer program products (i.e., physically embodied computer program products) that store instructions that, when executed by one or more data processors of one or more computing systems, cause at least one data processor to perform the operations described herein are also described. Similarly, computer systems that can include one or more data processors and memory coupled to the one or more data processors are also described. The memory may temporarily or permanently store instructions that cause at least one processor to perform one or more of the operations described herein. Furthermore, methods of the present invention can be implemented by one or more data processors within a single computing system or distributed among two or more computing systems. Such computing systems may be connected and may exchange data and / or commands or other instructions, etc., via one or more connections, including, but not limited to, connections over a network (e.g., the Internet, a wireless wide area network, a local area network, a wide area network, a wired network, etc.), such as via a direct connection between one or more of the computing systems.

[0023] The details of one or more variations of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features and advantages of the subject matter described herein will be apparent from the description and drawings, and from the claims.

[0024] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate certain aspects of the subject matter disclosed herein and, together with the description, serve to explain some of the principles associated with the disclosed implementations. [Brief explanation of the drawings]

[0025] [Figure 1a] FIG. 1a illustrates an exemplary conventional Long Term Evolution ("LTE") communication system.

[0026] [Figure 1b] FIG. 1b illustrates further details of the exemplary LTE system shown in FIG. 1a.

[0027] [Figure 1c] FIG. 1c illustrates additional details of the evolved packet core of the exemplary LTE system shown in FIG. 1a.

[0028] [Figure 1d] FIG. 1d illustrates an exemplary evolved Node B of the exemplary LTE system shown in FIG. 1a.

[0029] [Figure 2] FIG. 2 shows further details of the evolved Node B shown in FIGS. 1a-1d.

[0030] [Figure 3] FIG. 3 illustrates an exemplary virtual radio access network in accordance with some implementations of the present subject matter.

[0031] [Figure 4] FIG. 4 illustrates an exemplary 3GPP split architecture for providing use of higher frequency bands to its users.

[0032] [Figure 5a] FIG. 5a illustrates an exemplary 5G wireless communication system.

[0033] [Figure 5b] FIG. 5b illustrates an exemplary layer architecture of a split gNB and / or a split ng-eNB (e.g., a next-generation eNB that can connect to 5GC).

[0034] [Figure 5c] FIG. 5c illustrates an exemplary functional division in the gNB architecture shown in FIGS. 5a-5b.

[0035] [Figure 6] FIG. 6 is a diagram illustrating exemplary first and second signals according to some implementations of the present subject matter.

[0036] [Figure 7] FIG. 7 illustrates an exemplary method according to some implementations of the present subject matter.

[0037] [Figure 8a] FIG. 8a is a diagram illustrating exemplary first and second signals that may be transmitted and received in the method of FIG. 7 according to some implementations of the present subject matter.

[0038] [Figure 8b] FIG. 8b is a diagram illustrating the first and second signals of FIG. 8a and a single signal formed by combining the first and second signals, according to some implementations of the present subject matter.

[0039] [Figure 8c] FIG. 8c is a diagram illustrating subcarrier values, frequency offsets, and absolute frequency centers of the first and second signals of FIGS. 8a and 8b according to some implementations of the present subject matter.

[0040] [Figure 9a] FIG. 9a illustrates an exemplary system for processing and combining that may be performed in the method of FIG. 7, according to some implementations of the present subject matter.

[0041] [Figure 9b] FIG. 9b illustrates another exemplary system for processing and combining that may be performed in the method of FIG. 7, according to some implementations of the present subject matter.

[0042] [Figure 10a] FIG. 10a is a diagram illustrating the single signal of FIG. 8b and the null and non-null subcarrier values ​​of the first and second signals of FIGS. 8a-8c according to some implementations of the present subject matter.

[0043] [Figure 10b] FIG. 10b is a diagram illustrating null and non-null subcarrier values ​​of the first and second signals of FIG. 10a and non-null subcarrier values ​​of the single signal of FIG. 8b and FIG. 10a in accordance with some implementations of the present subject matter.

[0044] [Figure 11] FIG. 1 illustrates an exemplary system, in accordance with some implementations of the present subject matter.

[0045] [Figure 12] FIG. 1 illustrates another exemplary method, according to some implementations of the present subject matter. DETAILED DESCRIPTION OF THE INVENTION

[0046] The present subject matter can provide systems and methods that can be implemented in wireless communication systems. Such systems can include various wireless communication systems, including 5G New Radio (5G NR) communication systems, Long Term Evolution (LTE) communication systems, etc.

[0047] Generally, the present subject matter relates to flexible carrier bandwidth handling in wireless communication systems.

[0048] In some implementations of the present subject matter, two signals can be transmitted from one communication device in a wireless communication system to another communication device in the wireless communication system in two fixed operating bandwidths defined by 3GPP for the wireless communication system. The two defined fixed operating bandwidths can be the same or different from each other. Independently, neither signal contains a complete usable signal for further use in the communication system for each typical communication in the system. These signals are independently incomplete because they reflect the use of bandwidth that is not within the defined fixed operating bandwidths. However, these signals can be combined into a single signal that contains a complete usable signal for further use in the communication system. Thus, the single signal can be further used as needed for communication in the wireless communication system and can be communicated within the system using one of the defined fixed operating bandwidths. Thus, the bandwidth that is not within the defined fixed operating bandwidths can be used for communication in the wireless communication system and is not unused, wasted available resources.

[0049] Operators that provide cellular services to their customers may have the ability to use bandwidth that is not within a defined fixed operating bandwidth. Thus, such operators may be able to use these bandwidth resources that would otherwise be unused and wasted assets for the operator. For example, an operator may have the ability to use spectrum bandwidth released from a legacy network (e.g., 2G LTE, 3G LTE, etc.) that is not within a defined fixed operating bandwidth.

[0050] One or more aspects of the present subject matter may be incorporated into transmitter and / or receiver components of base stations (e.g., gNodeB, eNodeB, etc.) in such communication systems. The following is a general description of Long Term Evolution and 5G New Radio communication systems.

[0051] I. Long Term Evolution Communication System 1a-1c and 2 illustrate an exemplary conventional Long Term Evolution ("LTE") communication system 100 along with its various components. The LTE system, or 4G LTE, as it is commercially known, is governed by a standard for high-speed data wireless communication for mobile phones and data terminals. The standard is an evolution of GSM / EDGE ("Global System for Mobile Communications" / "Enhanced Data Rates for GSM Evolution") and UMTS / HSPA ("Universal System for Mobile Communications" / "High Speed ​​Packet Access") network technologies. The standard was developed by 3GPP ("Third Generation Partnership Project").

[0052] As shown in FIG. 1a, system 100 may include an Evolved Universal Terrestrial Radio Access Network (“EUTRAN”) 102, an Evolved Packet Core (“EPC”) 108, and a Packet Data Network (“PDN”) 101, where EUTRAN 102 and EPC 108 provide communications between user equipment 104 and PDN 101. EUTRAN 102 may include multiple evolved Node Bs (“eNodeB” or “ENODEB” or “enodeb” or “eNB”) or base stations 106(a, b, c) (as shown in FIG. 1b) that provide communications capabilities to multiple user equipment 104(a, b, c). User equipment 104 may be a mobile phone, a smartphone, a tablet, a personal computer, a personal digital assistant (“PDA”), a server, a data terminal, and / or any other type of user equipment, and / or any combination thereof. User equipment 104 can connect to the EPC 108 and ultimately to the PDN 101 via any eNodeB 106. Typically, user equipment 104 can connect to the nearest eNodeB 106 in terms of distance. In the LTE system 100, the EUTRAN 102 and the EPC 108 cooperate to provide connectivity, mobility, and services to user equipment 104.

[0053] Figure 1b shows further details of the network 100 shown in Figure 1a. As mentioned above, the EUTRAN 102 includes multiple eNodeBs 106, also known as cell sites. The eNodeBs 106 provide radio functionality and perform important control functions, including air link resource scheduling or radio resource management, active mode mobility or handover, and service-oriented admission control. The eNodeBs 106 are responsible for selecting which mobility management entity (MME, as shown in Figure 1c) will serve the user equipment 104, as well as protocol functions such as header compression and encryption. The eNodeBs 106 that make up the EUTRAN 102 cooperate with each other for radio resource management and handover.

[0054] Communication between the user equipment 104 and the eNodeB 106 occurs over an air interface 122 (also known as the "LTE-Uu" interface). As shown in FIG. 1b, the air interface 122 provides communication between the user equipment 104b and the eNodeB 106a. The air interface 122 uses orthogonal frequency division multiple access ("OFDMA") and single-carrier frequency division multiple access ("SC-FDMA"), an OFDMA variant, on the downlink and uplink, respectively. OFDMA allows the use of multiple known antenna technologies, such as multiple-input multiple-output ("MIMO").

[0055] The air interface 122 uses various protocols, including radio resource control ("RRC") for signaling between the user equipment 104 and the eNodeB 106 and non-access stratum ("NAS") for signaling between the user equipment 104 and the MME (shown in FIG. 1c). In addition to signaling, user traffic is transferred between the user equipment 104 and the eNodeB 106. Both signaling and traffic in the system 100 are carried by physical layer ("PHY") channels.

[0056] Multiple eNodeBs 106 can interconnect with each other using X2 interfaces 130(a, b, c). As shown in FIG. 1b, X2 interface 130a provides interconnection between eNodeB 106a and eNodeB 106b, X2 interface 130b provides interconnection between eNodeB 106a and eNodeB 106c, and X2 interface 130c provides interconnection between eNodeB 106b and eNodeB 106c. The X2 interfaces can be established between two eNodeBs to provide for the exchange of signals, which may include information related to loading or interference as well as information related to handover. The eNodeBs 106 communicate with the evolved packet core 108 via S1 interfaces 124(a, b, c). The S1 interface 124 can be split into two interfaces, one for the control plane (shown in Figure 1c as control plane interface (S1-MME interface) 128) and the other for the user plane (shown in Figure 1c as user plane interface (S1-U interface) 125).

[0057] The EPC 108 establishes and enforces quality of service ("QoS") for user services and allows the user equipment 104 to maintain a consistent Internet Protocol ("IP") address while moving. Note that each node in the network 100 has its own IP address. The EPC 108 is designed to interwork with legacy wireless networks. The EPC 108 is also designed to separate the control plane (i.e., signaling) and user plane (i.e., traffic) in the core network architecture, which allows for more flexibility in implementation and independent scalability of control and user data functions.

[0058] The EPC 108 architecture is dedicated to packet data and is shown in more detail in Figure 1c. The EPC 108 includes a Serving Gateway (S-GW) 110, a PDN Gateway (P-GW) 112, a Mobility Management Entity ("MME") 114, a Home Subscriber Server ("HSS") 116 (a subscriber database for the EPC 108), and a Policy Control and Charging Rules Function ("PCRF") 118. Some of these (such as the S-GW, P-GW, MME, and HSS) are often combined into nodes according to manufacturer implementations.

[0059] The S-GW 110 functions as an IP packet data router and is the bearer path anchor for user equipment within the EPC 108. Thus, when a user equipment moves from one eNodeB 106 to another during mobility operation, the S-GW 110 remains the same, and the bearer path towards the EUTRAN 102 is switched to communicate with the new eNodeB 106 serving the user equipment 104. If the user equipment 104 moves to the domain of a different S-GW 110, the MME 114 will forward all of the user equipment's bearer path to the new S-GW. The S-GW 110 establishes a bearer path for the user equipment to one or more P-GWs 112. When downstream data is received for an idle user equipment, the S-GW 110 buffers the downstream packets and requests the MME 114 to identify and re-establish the bearer path to and through the EUTRAN 102.

[0060] The P-GW 112 is the gateway between the EPC 108 (and user equipment 104 and EUTRAN 102) and the PDN 101 (shown in FIG. 1a). The P-GW 112 acts as a router for user traffic and performs functions on behalf of the user equipment. These include IP address allocation for the user equipment, packet filtering of downstream user traffic to ensure that it is placed on the appropriate bearer path, and enforcement of downstream QoS, including data rate. Depending on the services a subscriber is using, there may be multiple user data bearer paths between the user equipment 104 and the P-GW 112. A subscriber may use services on PDNs served by different P-GWs, in which case the user equipment has at least one bearer path established to each P-GW 112. During handover of a user equipment from one eNodeB to another, if the S-GW 110 is also changing, the bearer path from the P-GW 112 is switched to the new S-GW.

[0061] The MME 114 manages the user equipment 104 in the EPC 108, including managing subscriber authentication, maintaining context for authenticated user equipment 104, establishing a data bearer path within the network for user traffic, and tracking the location of idle mobiles that have not detached from the network. In the case of an idle user equipment 104 that needs to reconnect to the access network to receive downstream data, the MME 114 initiates paging to locate the user equipment and reestablishes a bearer path to and through the EUTRAN 102. The MME 114 for a particular user equipment 104 is selected by the eNodeB 106 from which the user equipment 104 initiates system access. The MME is typically part of a collection of MMEs in the EPC 108 for load sharing and redundancy purposes. In establishing a user's data bearer path, the MME 114 is responsible for selecting the P-GW 112 and S-GW 110, which constitute the termination of the data path through the EPC 108.

[0062] The PCRF 118 is responsible for controlling policy control decision-making and flow-based charging functionality within the Policy Control Enforcement Function ("PCEF") residing within the P-GW 110. The PCRF 118 provides QoS authorization (QoS Class Identifier ("QCI") and bit rate), which determines how a data flow is treated within the PCEF and ensures that this is in accordance with the user's subscription profile.

[0063] As mentioned above, IP services 119 are provided by PDN 101 (as shown in FIG. 1a).

[0064] 1d shows an example structure of an eNodeB 106. The eNodeB 106 may include at least one remote radio head (“RRH”) 132 (typically, there may be three RRHs 132) and a baseband unit (“BBU”) 134. The RRHs 132 may be connected to an antenna 136. The RRHs 132 and BBU 134 may be connected using an optical interface that conforms to the Common Public Radio Interface (“CPRI”) / enhanced CPRI (“eCPRI”) 142 standard specification, either using RRH-specific custom control and user plane framing methods or using O-RAN Alliance compliant control and user plane framing methods. The operation of the eNodeB 106 can be characterized using the following standard parameters (and specifications): radio frequency band (Band 4, Band 9, Band 17, etc.), bandwidth (5, 10, 15, 20 MHz), access method (downlink: OFDMA, uplink: SC-OFDMA), antenna technology (single-user and multi-user MIMO, uplink: single-user and multi-user MIMO), number of sectors (up to 6), maximum transmission speed (downlink: 150 Mb / s, uplink: 50 Mb / s), S1 / X2 interface (1000Base-SX, 1000Base-T), and mobile environment (up to 350 km / h). The BBU 134 can be responsible for digital baseband signal processing, S1 line termination, X2 line termination, call processing, and monitoring and control processing. IP packets received from the EPC 108 (not shown in FIG. 1d) can be modulated into digital baseband signals and transmitted to the RRH 132. Conversely, digital baseband signals received from the RRH 132 can be demodulated into IP packets for transmission to the EPC 108.

[0065] The RRH 132 can transmit and receive wireless signals using the antenna 136. The RRH 132 can convert digital baseband signals from the BBU 134 (using a converter (“CONV”) 140) to radio frequency (“RF”) signals and power amplify them (using an amplifier (“AMP”) 138) for transmission to the user equipment 104 (not shown in FIG. 1d). Conversely, RF signals received from the user equipment 104 are amplified (using AMP 138) and converted (using CONV 140) to digital baseband signals for transmission to the BBU 134.

[0066] Figure 2 shows additional details of an exemplary eNodeB 106. The eNodeB 106 includes multiple layers: LTE Layer 1 202, LTE Layer 2 204, and LTE Layer 3 206. LTE Layer 1 includes the physical layer ("PHY"). LTE Layer 2 includes Medium Access Control ("MAC"), Radio Link Control ("RLC"), and Packet Data Convergence Protocol ("PDCP"). LTE Layer 3 includes various functions and protocols, including Radio Resource Control ("RRC"), dynamic resource allocation, eNodeB measurement configuration and provisioning, radio admission control, connection mobility control, and radio resource management ("RRM"). The RLC protocol is an automatic repeat request ("ARQ") fragmentation protocol used over the cellular air interface. The RRC protocol handles LTE Layer 3 control plane signaling between user equipment and the EUTRAN. The RRC includes functions for connection establishment and release, system information broadcast, radio bearer establishment / reconfiguration and release, RRC connection mobility procedures, paging notification and release, and outer loop power control. The PDCP performs IP header compression and decompression, user data transfer, and radio bearer sequence number maintenance. The BBU 134 shown in FIG. 1d may include LTE layers L1-L3.

[0067] One of the primary functions of the eNodeB 106 is radio resource management, including scheduling of both uplink and downlink air interface resources for the user equipment 104, control of bearer resources, and admission control. As an agent for the EPC 108, the eNodeB 106 is responsible for forwarding paging messages used to locate a mobile when it is idle. The eNodeB 106 also communicates common control channel information over the air, performs header compression, encryption and decryption of user data sent over the air, and establishes handover reporting and trigger criteria. As mentioned above, the eNodeB 106 can cooperate with other eNodeBs 106 via the X2 interface for handover and interference management purposes. The eNodeB 106 communicates with the MME of the EPC via the S1-MME interface and with the S-GW using the S1-U interface. Additionally, the eNodeB 106 exchanges user data with the S-GW via the S1-U interface. The eNodeBs 106 and the EPC 108 have a many-to-many relationship to support load sharing and redundancy between MMEs and S-GWs. The eNodeB 106 selects an MME from a group of MMEs so that the load can be shared by multiple MMEs to avoid congestion.

[0068] II. 5G NR Wireless Communication Network In some implementations, the present subject matter relates to 5G New Radio ("NR") communication systems. 5G NR is the next communication standard beyond the 4G / IMT-Advanced standard. 5G networks offer higher capacity than current 4G, allowing for a larger number of mobile broadband users per unit area, and allowing for consumption of more and / or unlimited data amounts in gigabytes per month and per user. This can enable users to stream high-definition media for many hours per day using their mobile devices, even when Wi-Fi networks do not allow for this. 5G networks have improved support for device-to-device communications, lower costs, lower latency than 4G equipment, and lower battery consumption, among other benefits. Such a network would have data rates of tens of megabits per second for many users, data rates of 100 Mb / s for metropolitan areas, simultaneous 1 Gb / s to users within a limited area (e.g., an office floor), many simultaneous connections for wireless sensor networks, increased spectral efficiency, improved coverage, increased signaling efficiency, 1-10 ms latency, and reduced latency compared to existing systems.

[0069] 3 illustrates an exemplary virtual radio access network 300. The network 300 can provide communication between various components, including a base station (e.g., eNodeB, gNodeB) 301, radio equipment 303, a centralized unit 302, a digital unit 304, and a radio unit 306. The components in the system 300 can be communicatively coupled to the core using backhaul links 305. The centralized unit ("CU") 302 can be communicatively coupled to the distributed unit ("DU") 304 using a midhaul connection 308. The radio frequency ("RU") component 306 can be communicatively coupled to the DU 304 using a fronthaul connection 310.

[0070] In some implementations, the CU 302 can provide intelligent communication capabilities to one or more DU units 304. The units 302, 304 can include one or more base stations, macro base stations, micro base stations, remote radio heads, etc., and / or any combination thereof.

[0071] In a lower layer split architecture environment, the CPRI bandwidth requirement for NR can be several hundred Gb / s. CPRI compression can be implemented in the DU and RU (as shown in Figure 3). In 5G communication systems, compressed CPRI over Ethernet frames is called eCPRI and is the recommended fronthaul network. This architecture can enable standardization of fronthaul / midhaul, which can include upper layer splitting (e.g., Option 2 or Option 3-1 (upper / lower RLC split architecture)) and fronthaul using L1 split architecture (Option 7).

[0072] In some implementations, a lower layer split architecture (e.g., Option 7) can include receiver in the uplink and joint processing across multiple transmission points (TPs) for both DL / UL and transport bandwidth and latency requirements to facilitate deployment. Additionally, the subject lower layer split architecture can include splitting between cell-level processing and user-level processing, which can include cell-level processing in a remote unit ("RU") and user-level processing in a DU. Additionally, using the subject lower layer split architecture, frequency-domain samples can be transported over the Ethernet fronthaul, and the frequency-domain samples can be compressed for reduced fronthaul bandwidth.

[0073] 4 illustrates an example communication system 400 that can implement 5G technology and provide its users with access to higher frequency bands (e.g., greater than 10 GHz). System 400 can include a macro cell 402 and small cells 404 and 406.

[0074] The mobile device 408 can be configured to communicate with one or more of the small cells 404, 406. The system 400 can enable splitting of the control plane (C-plane) and user plane (U-plane) between the macrocell 402 and the small cells 404, 406, with the C-plane and U-plane utilizing different frequency bands. Specifically, the small cells 404, 406 can be configured to utilize higher frequency bands when communicating with the mobile device 408. The macrocell 402 can utilize existing cellular bands for C-plane communications. The mobile device 408 can be communicatively coupled via the U-plane 412, where the small cell (e.g., the small cell 406) can provide higher data rates and more flexible / cost / energy-efficient operation. The macrocell 402 can maintain good connectivity and mobility via the C-plane 410. Furthermore, in some cases, LTE and NR can transmit on the same frequency.

[0075] 5a illustrates an exemplary 5G wireless communication system 500 according to some implementations of the present subject matter. The system 500 may be configured to have a lower-layer split architecture according to Option 7-2. The system 500 may include a core network 502 (e.g., 5G Core) and one or more gNodeBs (or gNBs), where the gNBs may have a centralized unit gNB-CU. The gNB-CU may be logically divided into a control plane portion gNB-CU-CP 504 and one or more user plane portions gNB-CU-UP 506. The control plane portion 504 and the user plane portion 506 may be configured to be communicatively coupled using an E1 communication interface 514 (as defined in the 3GPP standard). The control plane portion 504 may be configured to be responsible for executing the RRC and PDCP protocols of the radio stack.

[0076] The control plane portion 504 and user plane portion 506 of the centralized unit of the gNB can be configured to be communicatively coupled to one or more distributed units (DUs) 508, 510 according to an upper layer split architecture. The distributed units 508, 510 can be configured to execute upper portions of the RLC, MAC, and PHY layer protocols of the radio stack. The control plane portion 504 can be configured to be communicatively coupled to the distributed units 508, 510 using an F1-C communication interface 516, and the user plane portion 506 can be configured to be communicatively coupled to the distributed units 508, 510 using an F1-U communication interface 518. The distributed units 508, 510 can be coupled to one or more remote radio units (RUs) 512 via a fronthaul network 520 (which may include one or more switches, links, etc.), which in turn communicate with one or more user equipment (not shown in FIG. 5a). The remote radio unit 512 may be configured to execute lower portions of the PHY layer protocol and provide antenna capabilities to the remote unit for communication with user equipment (similar to the description above in connection with Figures 1a-2).

[0077] Figure 5b shows an example layer architecture 530 for a split gNB. The architecture 530 can be implemented within the communication system 500 shown in Figure 5a, which can be configured as a virtualized disaggregated radio access network (RAN) architecture, whereby layers L1, L2, L3 and radio processing can be virtualized and disaggregated within centralized units, distributed units, and radio units. As shown in Figure 5b, the gNB-DU 508 can be communicatively coupled to the gNB-CU-CP control plane portion 504 (also shown in Figure 5a) and the gNB-CU-UP user plane portion 506. Each of the components 504, 506, 508 can be configured to include one or more layers.

[0078] The gNB-DU 508 may include RLC, MAC, and PHY layers, as well as various communication sublayers. These may include an F1-Application Protocol (F1-AP) sublayer, a GPRS Tunneling Protocol (GTPU) sublayer, a Stream Control Transmission Protocol (SCTP) sublayer, a User Datagram Protocol (UDP) sublayer, and an Internet Protocol (IP) sublayer. As described above, the distributed unit 508 may be communicatively coupled to the control plane portion 504 of the centralized unit, which may also include the F1-AP, SCTP, and IP sublayers, as well as the Radio Resource Control and PDCP Control (PDCP-C) sublayer. Furthermore, the distributed unit 508 may also be communicatively coupled to the user plane portion 506 of the centralized unit of the gNB. The user plane portion 506 may include the Service Data Adaptation Protocol (SDAP), PDCP User (PDCP-U), GTPU, UDP, and IP sublayers.

[0079] Figure 5c shows an example functional division in the gNB architecture shown in Figures 5a-5b. As shown in Figure 5c, the gNB-DU 508 can be communicatively coupled to the gNB-CU-CP 504 and the GNB-CU-UP 506 using an F1-C communication interface. The gNB-CU-CP 504 and the GNB-CU-UP 506 can be communicatively coupled using an E1 communication interface. An upper portion of the PHY layer (or L1) can be performed by the gNB-DU 508, and a lower portion of the PHY layer can be performed by the RU (not shown in Figure 5c). As shown in Figure 5c, the RRC portion and the PDCP-C portion can be performed by the control plane portion 504, and the SDAP portion and the PDCP-U portion can be performed by the user plane portion 506.

[0080] Some of the functions of the PHY layer in a 5G communication network include error detection on transport channels and indication to higher layers, FEC encoding / decoding of transport channels, hybrid ARQ soft combining, rate matching of coded transport channels to physical channels, mapping of coded transport channels to physical channels, power weighting of physical channels, modulation and demodulation of physical channels, frequency and time synchronization, radio characteristic measurements and indication to higher layers, MIMO antenna processing, digital and analog beamforming, RF processing, and other functions.

[0081] The L2 MAC sublayer performs beam management, random access procedures, mapping between logical channels and transport channels, concatenation of multiple MAC service data units (SDUs) belonging to one logical channel into transport blocks (TBs), multiplexing / demultiplexing of SDUs belonging to logical channels to / from TBs passed to / from the physical layer on transport channels, scheduling information reporting, error correction using HARQ, priority handling between logical channels for one UE, priority handling between UEs using dynamic scheduling, transport format selection, and other functions. The RLC sublayer's functions include forwarding upper-layer packet data units (PDUs), error correction using ARQ, reordering of data PDUs, duplication and protocol error detection, reestablishment, etc. The PDCP sublayer is responsible for forwarding user data, various functions during reestablishment procedures, retransmission of SDUs, discarding SDUs in the uplink, forwarding of control plane data, etc.

[0082] The L3 RRC sublayer may perform broadcasting of system information to the NAS and AS, establishment, maintenance, and release of RRC connections, security, establishment, configuration, maintenance, and release of point-to-point radio bearers, mobility functions, reporting, and other functions.

[0083] III. Flexible Carrier Bandwidth Processing in Wireless Communication Systems In some implementations of the present subject matter, two signals can be transmitted from one communication device in a wireless communication system to another communication device in the wireless communication system in two fixed operating bandwidths defined by 3GPP for the wireless communication system. The two defined fixed operating bandwidths can be the same or different from each other. Independently, neither signal contains a complete usable signal for further use in the communication system for each typical communication in the system. These signals are independently incomplete because they reflect the use of bandwidth that is not within the defined fixed operating bandwidths. However, these signals can be combined into a single signal that contains a complete usable signal for further use in the communication system. Thus, the single signal can be further used as needed for communication in the wireless communication system and can be communicated within the system using one of the defined fixed operating bandwidths. Thus, the bandwidth that is not within the defined fixed operating bandwidths can be used for communication in the wireless communication system and is not unused, wasted available resources.

[0084] In some implementations of the present subject matter, a communication device (e.g., a first communication device) that receives a signal may include one of an RU (e.g., the RU 306 in FIG. 3 , the RU 512 in FIG. 5 a, etc.) and a DU (e.g., the DU 304 in FIG. 3 , the DUs 508, 510 in FIGS. 5 a-5 c, etc.), and a communication device (e.g., a second communication device) that transmits a signal to the first communication device may include the other of the RU and the DU. In this manner, the UE may communicate with the RU using a non-standard bandwidth (e.g., a bandwidth that is not within the fixed operating bandwidth defined by 3GPP for the wireless communication system), and the RU may process signals received over the non-standard bandwidth for further use in the wireless communication system that uses the defined fixed operating bandwidth. In implementations in which the first communication device that receives the first signal and the second signal includes a DU and the second communication device that transmits the first signal and the second signal includes an RU, the communication of the signals is uplink communication. In an implementation in which the first communication device that receives the first signal and the second signal includes an RU and the second communication device that transmits the first signal and the second signal includes a DU, the communication of the signals is downlink communication.

[0085] The LTE wireless communication system uses frequency bands that support the channel bandwidths specified in the 3GPP standard (3GPP TS 36.101): 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz, and 20 MHz. Thus, in implementations where the wireless communication system is an LTE wireless communication system, a single signal generated from multiple signals can be aligned with one of these defined fixed operating bandwidths.

[0086] 5G NR wireless communication systems also use frequency bands that support the channel bandwidths specified in the 3GPP standard (3GPP TS 38.101): 5 MHz, 10 MHz, 15 MHz, 20 MHz, 25 MHz, 30 MHz, 35 MHz, 40 MHz, 45 MHz, 50 MHz, 60 MHz, 70 MHz, 80 MHz, 90 MHz, and 100 MHz. Thus, in implementations where the wireless communication system is a 5G NR wireless communication system, a single signal generated from multiple signals can be aligned with one of these defined fixed operating bandwidths.

[0087] Each of the first and second signals transmitted by one communication device and received by another communication device can be considered a component carrier (CC). Combining the first and second signals can be considered carrier aggregation (CA). Wireless communication systems such as LTE and 5G NR support the use of CC and CA.

[0088] Table 1 shows several example carrier bandwidths of a first signal (CC1 carrier bandwidth) and a second signal (CC2 carrier bandwidth), each of which is aligned with one of the fixed operating bandwidths defined for an LTE wireless communications system. Table 1 also shows, for each of the example first and second signals, the aggregate bandwidth reflected by the first and second signals. The aggregate bandwidth is not one of the fixed operating bandwidths defined for an LTE wireless communications system. [Table 1]

[0089] FIG. 6 illustrates one of the examples shown in Table 1, specifically the third row from the bottom. As shown in FIG. 6, a first signal 600 is transmitted from a communication device using a defined fixed operating bandwidth of 20 MHz, and a second signal 602 is transmitted from the communication device using a defined fixed operating bandwidth of 5 MHz. The aggregate bandwidth of the first signal 600 and the second signal 602 is an undefined bandwidth of 23.9 MHz, as reflected by the overlap 606 of the first signal 600 and the second signal 602. While the first signal 600 and the second signal 602 in FIG. 6 are transmitted at different fixed operating bandwidths, they could alternatively be transmitted at the same fixed operating bandwidth, as shown, for example, in rows 1, 3, and 6 of Table 1.

[0090] Table 1 is in the context of LTE, where in each row, the first and second carrier bandwidths are each one of the defined fixed operating bandwidths for the LTE wireless communications system, and the associated aggregate bandwidth is not one of the defined fixed operating bandwidths for the LTE wireless communications system. The carrier bandwidths and aggregate bandwidths may similarly be used in another, e.g., 5G NR, wireless communications system, where the first and second carrier bandwidths are each one of the defined fixed operating bandwidths for the other, e.g., 5G NR, wireless communications system, and the associated aggregate bandwidth is not one of the defined fixed operating bandwidths for the other, e.g., 5G NR, wireless communications system.

[0091] Wireless communication systems using the Radio Access Network (RAN) architecture can be implemented in accordance with O-RAN Alliance standards. Such standards currently do not allow for the use of undefined fixed operating bandwidths. In the context of the O-RAN split RAN architecture (split 7-2x) with lower layers, the functions of the O-DU (Distributed Unit (DU) of the O-RAN architecture) and the O-RU (Radio Unit (RU) of the O-RAN architecture) are defined in the Control, User, and Synchronization Plane Specification of O-RAN Working Group 4 (Open Fronthaul Interface WG) and the Management Plane Specification of O-RAN Working Group 4 (Open Fronthaul Interface WG). In the split 7-2x interface, the O-RAN Alliance provides that the fronthaul network resides between the resource element mapping in the O-DU and the time-frequency conversion in the O-RU. In the downlink (DL) direction, subcarrier mapping can be performed, and data can be converted from the frequency domain to the time domain by applying inverse fast Fourier transform (IFFT) processing and performing cyclic prefix (CP) addition. In the uplink (UL) direction, subcarrier demapping can be performed and data can be transformed from the time domain to the frequency domain by performing CP removal and applying FFT processing.

[0092] In some implementations, the present subject matter can be applied in the division 7-2x interface defined by the O-RAN Alliance, hi some implementations, the present subject matter can be applied in another existing division (e.g., Division-6 by the Small Cell Forum), or in a future interface (e.g., 7-2C, 7-3, etc.).

[0093] In some implementations of the present subject matter, a method for flexible carrier bandwidth processing in a wireless communication system may include a first signal and a second signal transmitted from one communication device (e.g., one of an RU and a DU) in the wireless communication system to another communication device (e.g., the other of the RU and the DU) in the wireless communication system, where each of the first signal and the second signal is transmitted using a bandwidth within a fixed operating bandwidth defined by 3GPP for the wireless communication system. Each of the first signal and the second signal may include at least one null subcarrier value and at least one non-null subcarrier value. The at least one null subcarrier value in the first signal and the second signal reflects a non-standard bandwidth. In other words, neither signal includes a complete usable signal, and therefore one or more subcarrier values ​​are null in the signal. The first signal and the second signal may be combined into a single signal that does not include the at least one null subcarrier value in the first signal and the second signal. Thus, the single signal may include only non-null subcarrier values, thereby being a complete usable signal that can match one of the defined fixed operating bandwidths. Thus, bandwidth that is not within the defined fixed operating bandwidth may be used for communications in the wireless communications system and is therefore not unused wasted available resource.

[0094] 7 illustrates one implementation of a method 700 for flexible carrier bandwidth processing in a wireless communication system in accordance with some implementations of the present subject matter. Method 700 is described with respect to O-RAN partitioning 7-2x, but may be similarly implemented with other partitionings. Also, method 700 is described with respect to an LTE wireless communication system, but may be similarly implemented with other wireless communication systems, such as 5G NR.

[0095] The method 700 may include a handshake 702 between a first communication device and a second communication device. As mentioned above, in some implementations of the present subject matter, the first communication device and the second communication device may include a DU (e.g., the DU 304 in FIG. 3, the DUs 508, 510 in FIGS. 5a-5c, etc.) and an RU (e.g., the RU 306 in FIG. 3, the RU 512 in FIG. 5a, etc.). The method 700 is described with respect to a DU and an RU, and in particular an O-DU and an O-RU.

[0096] By performing handshake 702, it can be established that the use of overlapping subcarrier signals, each having at least one null subcarrier value, is valid. Thus, handshake 702 can signal the RU's ability to support overlapped mapping / demapping of subcarriers from two different component carriers. Therefore, errors due to receiving overlapping subcarriers, such as signal collisions, can be avoided.

[0097] Execution of handshake 702 may be triggered when a fronthaul connection is established between the RU and DU, so that the RU and DU can quickly establish that the use of overlapping subcarrier signals, each having at least one null subcarrier value, is valid to avoid any errors associated with overlapping subcarrier signals.

[0098] Method 700 may also include, after handshake 702, one of the RU and DU transmitting 704, e.g., over a fronthaul network, a first signal 800 and a second signal 802 (see FIG. 8a) to the other of the RU and DU. The first signal 800 and the second signal 802 are adjacent to each other and are each transmitted using a defined fixed operating bandwidth that may be different or the same, reflecting the use of bandwidth that is not within the defined fixed operating bandwidth. The first signal 800 and the second signal 802 each include subcarrier signals having overlap 804. For example, the first signal 800 and the second signal 802 may be the first signal 600 and the second signal 602 of FIG. 6 having overlap 604.

[0099] The other of the RU and DU receives (706) each of the first signal 800 and the second signal 802. As shown in FIG. 8b, after receiving (706) the first signal 800 and the second signal 802, the receiving one of the RU and DU processes and combines (708) the first signal 800 and the second signal 802 into a single signal 806.

[0100] Processing 708 the first signal 800 and the second signal 802 may include multiplexing the first signal 800 and the second signal 802. The multiplexing may be performed in accordance with 3GPP and O-RAN standards.

[0101] After the first signal 800 and the second signal 802 are multiplexed, IFFT / FFT processing can be performed. Processing 708 the first signal 800 and the second signal 802 may include using one IFFT / FFT engine or may include using two IFFT / FFT engines.

[0102] 9a, processing 708 the first signal 800 and the second signal 802 may include using one IFFT / FFT engine 904 after the first signal 800 and the second signal 802 are multiplexed, for example, using a multiplexer 900. Although engine 904 is shown in FIG. 9a as an IFFT engine 904 representing downlink communications, engine 904 may instead be an FFT engine representing uplink communications.

[0103] Prior to IFFT / FFT processing, the first signal 800 and the second signal 802 may be combined 708 using a combiner 902 .

[0104] According to the O-RAN Alliance, frequency offset (freqOffset) information received in the C-plane, e.g., by either an RU or a DU, indicates the location of the center of the lowest resource element (RE) in the lowest resource block (RB) defined by the frame structure relative to the channel bandwidth center. An RE is one subcarrier in an Orthogonal Frequency Division Multiplexing (OFDM) symbol. A physical resource block (PRB) is a group of 12 subcarriers in an OFDM signal. Also, according to the O-RAN Alliance, absolute frequency center offset information received in the management plane (M-plane), e.g., by either an RU or a DU, indicates that the location of the center of the lowest RE in the lowest RB defined by the frame structure relative to the channel bandwidth center unit is 1 / 2 subcarrier spacing (SCS).

[0105] Figure 8c shows the frequency offset 808 of the received first signal 800 and the absolute frequency center 810 of the received first signal 800. Figure 8c also shows the frequency offset 812 of the received second signal 802 and the absolute frequency center 814 of the received second signal 802.

[0106] Because the RU or DU receiving 706 the first signal 800 and the second signal 802 knows the frequency offsets 808, 812 and absolute frequency centers 810, 814 of the received first signal 800 and second signal 802, the RU or DU can therefrom determine the overlap 804 of the first signal 800 and the second signal 802, e.g., the frequency and time domain offsets of the first signal 800 and the second signal 802. In this manner, detecting the subcarrier overlap 804 can be achieved using the digital domain IQ data transmitted in the frequency domain of each of the first signal 800 and the second signal 802, and using the symbol duration transmitted in the time domain of each of the first signal 800 and the second signal 802. Due to the previously performed handshake 702, one of the RU and DU receiving 706 the first signal 800 and the second signal 802 knows that the overlap 804 between the signals 800, 802 is acceptable and therefore no errors will occur due to the overlap 804.

[0107] Figures 8b and 8c also show subcarrier values ​​816, 818 of the first signal 800 and the second signal 802. Figures 8b and 8c show the first signal 800 as including 14 subcarrier values ​​816 and the second signal 802 as including 8 subcarrier values ​​818. The first signal 800 and the second signal 802 can each include a different number of subcarrier values. Typically, OFDM signals such as the first signal 800 and the second signal 802 include more than 8 or 14 subcarrier values.

[0108] Upon detecting the overlap 804 of the first signal 816 and the second signal 818, subcarrier values ​​816, 818 within the overlap 804 can be identified. As shown in Figure 10a, three subcarrier values ​​816a, 816b, and 816c of the first signal 800 are within the overlap 804, and three subcarrier values ​​818a, 818b, and 818c of the second signal 802 are within the overlap 804. The overlapping subcarrier values ​​816a, 816b, 816c, 818a, 818b, and 818c each have a null value, indicated by an "x" in Figure 10a, for those subcarrier values ​​816a, 816b, 816c, 818a, 818b, and 818c. Thus, the first signal 800 and the second signal 802 each include at least one null subcarrier value, e.g., three null subcarrier values, although other numbers of null subcarrier values ​​are possible (e.g., depending on the overlap size). The remainder of the subcarrier values ​​816 of the first signal 800 (e.g., 11 subcarrier values ​​816) and the remainder of the subcarrier values ​​818 of the second signal 802 (e.g., 5 subcarrier values ​​818) each have a non-null subcarrier value, indicated by the absence of an "x" in Figure 10a for those subcarrier values ​​816, 818.

[0109] The combining 708 of the first signal 800 and the second signal 802 performed by the combiner 902 may include removing subcarrier values ​​816a, 816b, 816c, 818a, 818b, 818c that have null values, e.g., removing subcarrier values ​​816a, 816b, 816c, 818a, 818b, 818c within the overlap 804, and merging subcarrier values ​​816, 818 that have non-null values ​​into one signal to form the single signal 806 shown in Figures 8b, 10a, and 10b. Figure 10b also shows the absolute frequency center 820 of the single signal 806.

[0110] 10a, null subcarrier values ​​816a, 816b, 816c of the first signal 800 follow the non-null subcarrier value 816 of the first signal 800, and null subcarrier values ​​818a, 818b, 818c of the second signal 802 precede the non-null subcarrier value 818 of the second signal 802. Thus, merging the subcarrier values ​​816, 818 having non-null values ​​into one signal includes using the preceding subcarrier value 816 of the first signal 800 as the preceding subcarrier value of the single combined signal 806 and using the following subcarrier value 818 of the second signal 802 as the following subcarrier value of the single combined signal 806. Thus, a single signal 806 may include only non-null subcarrier values, for example, all non-null subcarrier values ​​816 of the first signal 800 followed by all non-null subcarrier values ​​818 of the second signal 802.

[0111] 9a, after the combiner 902 combines the first signal 800 and the second signal 802 to form a single signal 806, the single signal 806 may be further processed 708 for use in further communications according to 3GPP. As shown in FIG. 9a, the processing 708 may include applying an IFFT to the single signal 806 using an IFFT engine 904, then processing the resulting signal using a digital-to-analog converter 906, then applying a pulse 908 to the resulting signal, then processing the resulting signal using a radio frequency (RF) power amplifier (PA) 910, and then filtering the resulting signal using an RF filter 912.

[0112] 9b, the processing 708 of the first signal 800 and the second signal 802 can include using two IFFT / FFT engines 916a, 916b. In this implementation, the first signal 800 and the second signal 802 are processed on parallel tracks from multiplexing to RF power amplification before being combined into a single signal 806 by a combiner 926.

[0113] As shown in Figure 9b, after the first signal 800 and the second signal 802 are multiplexed using, for example, a first multiplexer 914a for the first signal 800 and a second multiplexer 914b for the second signal 802 and filtered using a filter 916, the multiplexed first and second signals can be processed using a first IFFT engine 918a and a second IFFT engine 918b, respectively. Although engines 918a, 918b are shown as IFFT engines 918a, 918b in Figure 9b illustrating downlink communication, engines 918a, 918b may instead be FFT engines illustrating uplink communication. Processing 708 may then include processing each of the two resulting signals using a first digital-to-analog converter 920a and a second digital-to-analog converter 920b, respectively, then applying a first pulse 922a and a second pulse 922b to the two resulting signals, respectively, and then processing the resulting signals using a first RF PA 924a and a second RF PA 924b, respectively. The resulting signals may then be combined using a combiner 926 similar to that described above with respect to combiner 902 of FIG. 9a. The resulting signals may then be filtered using an RF filter 928.

[0114] In some implementations, the present subject matter can be configured to be implemented in a system 1100, as shown in FIG. 11 . The system 1100 can include one or more of a processor 1110, a memory 1120, a storage device 1130, and an input / output device 1140. Each of the components 1110, 1120, 1130, and 1140 can be interconnected using a system bus 1150. The processor 1110 can be configured to process instructions for execution within the system 600. In some implementations, the processor 1110 can be a single-threaded processor. In alternative implementations, the processor 1110 can be a multi-threaded processor. The processor 1110 can be further configured to process instructions stored in the memory 1120 or the storage device 1130, including receiving or transmitting information through the input / output device 1140. The memory 1120 can store information within the system 1100. In some implementations, the memory 1120 can be a computer-readable medium. In alternative implementations, memory 1120 can be a volatile memory unit. Further, in some implementations, memory 1120 can be a non-volatile memory unit. Storage device 1130 may be capable of providing mass storage for system 1100. In some implementations, storage device 1130 can be a computer-readable medium. In alternative implementations, storage device 1130 can be a floppy disk device, a hard disk device, an optical disk device, a tape device, a non-volatile solid-state memory, or any other type of storage device. Input / output device 1140 can be configured to provide input / output operations to system 1100. In some implementations, input / output device 1140 can include a keyboard and / or a pointing device. In alternative implementations, input / output device 1140 can include a display unit for displaying a graphical user interface.

[0115] 12 illustrates an example method 1200 for flexible carrier bandwidth processing in a wireless communication system in accordance with some implementations of the present subject matter. Method 1200 can be performed, for example, using the implementations shown in and described with respect to FIGS.

[0116] The method 1200 includes receiving 1202, at a first communication device (e.g., an RU) in a cellular network (e.g., an LTE network, a 5G NR network, etc.), from a second communication device in the cellular network, a first signal in a first fixed operating bandwidth of a plurality of fixed operating bandwidths defined for the cellular network (e.g., defined by 3GPP) and a second signal in a second fixed operating bandwidth of a plurality of fixed operating bandwidths defined for the cellular network. The first signal and the second signal may have subcarrier overlap, where the first signal may include at least one null subcarrier value and at least one non-null subcarrier value, and the second signal may include at least one null subcarrier value and at least one non-null subcarrier value. The method also includes combining 1204 the first signal and the second signal into a single signal that does not include the at least one null subcarrier value of the first signal and does not include the at least one null subcarrier value of the second signal.

[0117] In some implementations, the present subject matter can include one or more of the following optional features.

[0118] In some implementations, at least one null subcarrier value of the first signal can follow at least one non-null subcarrier value of the first signal, and at least one null subcarrier value of the second signal can precede at least one non-null subcarrier value of the second signal, and combining the first and second signals into a single signal can include using at least one non-null subcarrier value of the first signal as a preceding subcarrier value of the single signal and using at least one non-null subcarrier value of the second signal as a following subcarrier value of the single signal that follows all of the preceding subcarrier values.

[0119] In some implementations, an error condition may occur when at least one null subcarrier value of a first signal precedes at least one non-null subcarrier value of the first signal and at least one non-null subcarrier value of a second signal precedes at least one null subcarrier value of the second signal.

[0120] In some implementations, at least one non-null subcarrier value of the first signal may overlap with at least one null subcarrier value of the second signal, and at least one non-null subcarrier value of the second signal may overlap with at least one null subcarrier value of the first signal.

[0121] In some implementations, the method may further include, after combining the first signal and the second signal into a single signal, applying IFFT or FFT processing to the single signal.

[0122] In some implementations, the method may further include applying IFFT or FFT processing to the first signal and applying IFFT or FFT processing to the second signal before combining the first signal and the second signal into a single signal.

[0123] In some implementations, the single signal may reflect a bandwidth that is not one of multiple fixed operating bandwidths defined for the cellular network.

[0124] In some implementations, the method can further include performing a handshake between the first communication device and the second communication device that establishes an understanding that the binding will be performed at a later time.

[0125] In some implementations, the method may further include detecting subcarrier overlap using digital domain IQ data transmitted in the frequency domain of each of the first signal and the second signal and using symbol duration transmitted in the time domain of each of the first signal and the second signal, which detecting may facilitate combining the first signal and the second signal into a single signal.

[0126] In some implementations, one of the first communication device and the second communication device may include a distributed unit (e.g., the DU 304 in FIG. 3, the DU 508, 510 in FIGS. 5a-5c, etc.), and the other of the first communication device and the second communication device may include a radio unit (e.g., the RU 306 in FIG. 3, the RU 512 in FIG. 5a, etc.). Furthermore, the first communication device that receives the first signal and the second signal may include the distributed unit, and the second communication device may include the radio unit such that the communication is uplink communication, or the first communication device that receives the first signal and the second signal may include the radio unit, and the second communication device may include the distributed unit such that the communication is downlink communication. Furthermore, the first communication device may perform the combining.

[0127] In some implementations, the cellular network may be a 3GPP LTE network. Further, the single signal may reflect a bandwidth that is not one of multiple fixed operating bandwidths defined for the network (e.g., defined by 3GPP TS36.101).

[0128] In some implementations, the cellular network may be a 5G network. Further, the single signal may reflect a bandwidth that is not one of multiple fixed operating bandwidths defined for the network (e.g., defined by 3GPP TS38.101).

[0129] The systems and methods disclosed herein may be embodied in various forms, including, for example, a data processor such as a computer, including a database, digital electronic circuitry, firmware, software, or any combination thereof. Furthermore, the above-described features and other aspects and principles of the implementations of the present disclosure may be implemented in a variety of environments. Such environments and associated applications may be specially constructed to perform the various processes and operations in accordance with the disclosed implementations, or they may comprise general-purpose computers or computing platforms selectively activated or reconfigured by code to provide the required functionality. The processes disclosed herein are not inherently related to any particular computer, network, architecture, environment, or other apparatus, but may be implemented by any suitable combination of hardware, software, and / or firmware. For example, various general-purpose machines may be used with programs written in accordance with the teachings of the disclosed implementations, or it may be more convenient to construct specialized apparatus or systems to perform the required methods and techniques.

[0130] The systems and methods disclosed herein can be implemented as a computer program product, i.e., a computer program tangibly embodied in an information carrier, e.g., a machine-readable storage device or a propagated signal, for execution by or to control the operation of a data processing apparatus, e.g., a programmable processor, a computer, or multiple computers. The computer program can be written in any type of programming language, including compiled or interpreted languages, and can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. The computer program can be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communications network.

[0131] As used herein, the term "user" can refer to any entity, including a person or a computer.

[0132] Although ordinal numbers such as first, second, etc. can relate to order in some circumstances, as used in this document, ordinal numbers do not necessarily imply order. For example, ordinal numbers may be used simply to distinguish one item from another. For example, distinguishing a first event from a second event need not imply any chronological order or fixed frame of reference (just as a first event in one paragraph of description may differ from a first event in another paragraph of description).

[0133] The foregoing description is intended to illustrate, but not to limit, the scope of the invention, which is defined by the appended claims. Other implementations are within the scope of the following claims.

[0134] These computer programs, which may also be referred to as programs, software, software applications, applications, components, or code, include machine instructions for a programmable processor and may be implemented in a high-level procedural and / or object-oriented programming language and / or in assembly / machine language. As used herein, the term “machine-readable medium” refers to any computer program product, apparatus, and / or device used to provide machine instructions and / or data to a programmable processor, such as, for example, a magnetic disk, an optical disk, a memory, and a programmable logic device (PLD), including a machine-readable medium that receives machine instructions as a machine-readable signal. The term “machine-readable signal” refers to any signal used to provide machine instructions and / or data to a programmable processor. A machine-readable medium may non-transitory store such machine instructions, such as, for example, a non-transitory solid-state memory or a magnetic hard drive or any equivalent storage medium. Alternatively or additionally, a machine-readable medium may temporarily store such machine instructions, such as, for example, a processor cache or other random access memory associated with one or more physical processor cores.

[0135] To provide for user interaction, the subject matter described herein can be implemented on a computer having a display device, such as a cathode ray tube (CRT) or liquid crystal display (LCD) monitor, for displaying information to the user, and a keyboard and pointing device, such as a mouse or trackball, by which the user can provide input to the computer. Other types of devices can also be used to provide for user interaction. For example, feedback provided to the user can be any form of sensory feedback, such as visual feedback, auditory feedback, or tactile feedback, and input from the user can be received in any form, including, but not limited to, acoustic input, speech input, or tactile input.

[0136] The subject matter described herein can be implemented in a computing system that includes back-end components, such as, for example, one or more data servers, or includes middleware components, such as, for example, one or more application servers, or includes front-end components, such as, for example, one or more client computers having a graphical user interface or web browser through which a user can interact with an implementation of the subject matter described herein, or any combination of such back-end, middleware, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication, such as, for example, a communications network. Examples of communications networks include, but are not limited to, a local area network ("LAN"), a wide area network ("WAN"), and the Internet.

[0137] A computing system may include clients and servers. Clients and servers are generally, but not exclusively, remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other.

[0138] The implementations described in the foregoing description do not represent all implementations consistent with the subject matter described herein. Rather, they are merely some examples consistent with aspects related to the described subject matter. While several variations have been described in detail above, other modifications or additions are possible. In particular, additional features and / or variations may be provided in addition to those described herein. For example, the implementations described above may be directed to various combinations and subcombinations of the disclosed features and / or combinations and subcombinations of certain additional features disclosed above. Additionally, the logic flow illustrated in the accompanying figures and / or described herein does not necessarily require the particular order shown, or sequential order, to achieve desirable results. Other implementations may be within the scope of the following claims.

Claims

1. 1. A computer-implemented method comprising: receiving, at a first communication device in a cellular network, from a second communication device in the cellular network, a first signal in a first fixed operating bandwidth of a plurality of fixed operating bandwidths defined for the cellular network and a second signal in a second fixed operating bandwidth of the plurality of fixed operating bandwidths defined for the cellular network, wherein the first signal and the second signal have subcarrier overlap, the first signal includes at least one null subcarrier value and at least one non-null subcarrier value, and the second signal includes at least one null subcarrier value and at least one non-null subcarrier value; and combining the first signal and the second signal into a single signal that does not include the at least one null subcarrier value of the first signal and that does not include the at least one null subcarrier value of the second signal; A method comprising:

2. the at least one null subcarrier value of the first signal follows the at least one non-null subcarrier value of the first signal; the at least one null subcarrier value of the second signal precedes the at least one non-null subcarrier value of the second signal; and combining the first signal and the second signal into the single signal includes using the at least one non-null subcarrier value of the first signal as a leading subcarrier value of the single signal, and using the at least one non-null subcarrier value of the second signal as a trailing subcarrier value of the single signal that follows all of the leading subcarrier values. The method of claim 1.

3. an error condition occurs when the at least one null subcarrier value of the first signal precedes the at least one non-null subcarrier value of the first signal and the at least one non-null subcarrier value of the second signal precedes the at least one null subcarrier value of the second signal; The method of claim 1.

4. the at least one non-null subcarrier value of the first signal overlaps with the at least one null subcarrier value of the second signal; and the at least one non-null subcarrier value of the second signal overlaps with the at least one null subcarrier value of the first signal; 4. The method according to any one of claims 1 to 3.

5. after combining the first signal and the second signal into the single signal, applying an inverse fast Fourier transform ("IFFT") or fast Fourier transform ("FFT") process to the single signal; 5. The method according to any one of claims 1 to 4.

6. before combining the first signal and the second signal into the single signal; applying an inverse fast Fourier transform ("IFFT") or fast Fourier transform ("FFT") process to the first signal; and applying IFFT or FFT processing to the second signal.

5. The method according to any one of claims 2 to 4.

7. the single signal reflects a bandwidth that is not one of the plurality of fixed operating bandwidths defined for the cellular network; 7. The method according to any one of claims 1 to 6.

8. performing a handshake between the first communication device and the second communication device establishing an understanding that the combining will be performed at a later time.

8. The method according to any one of claims 1 to 7.

9. detecting the subcarrier overlap using digital domain IQ data transmitted in the frequency domain of each of the first signal and the second signal, and using symbol duration transmitted in the time domain of each of the first signal and the second signal; wherein: the detecting facilitates the combining of the first signal and the second signal into the single signal.

9. The method according to any one of claims 1 to 8.

10. one of the first communication device and the second communication device includes a distributed unit, and the other of the first communication device and the second communication device includes a radio unit; 10. The method according to any one of claims 1 to 9.

11. the first communication device receiving the first signal and the second signal includes the distribution unit, and the second communication device includes the radio unit such that the communication is an uplink communication; The method of claim 10.

12. the first communication device receiving the first signal and the second signal includes the radio unit, and the second communication device includes the distributed unit such that the communication is a downlink communication; The method of claim 10.

13. the first communication device performs the combining; The method of claim 10.

14. the cellular network is a 3rd Generation Partnership Project ("3GPP") Long Term Evolution ("LTE") network; 14. The method of any one of claims 1 to 13.

15. The cellular network is a 5G network.

14. The method of any one of claims 1 to 13.

16. the single signal reflects a bandwidth that is not one of the plurality of fixed operating bandwidths defined for the network; 16. The method of claim 14 or 15.

17. 1. An apparatus comprising: at least one processor; at least one non-transitory storage medium that, when executed by the at least one processor, causes the at least one processor to: receiving, at a first communication device in a cellular network, from a second communication device in the cellular network, a first signal in a first fixed operating bandwidth of a plurality of fixed operating bandwidths defined for the cellular network and a second signal in a second fixed operating bandwidth of the plurality of fixed operating bandwidths defined for the cellular network, wherein the first signal and the second signal have subcarrier overlap, the first signal includes at least one null subcarrier value and at least one non-null subcarrier value, and the second signal includes at least one null subcarrier value and at least one non-null subcarrier value; and combining the first signal and the second signal into a single signal that does not include the at least one null subcarrier value of the first signal and that does not include the at least one null subcarrier value of the second signal; at least one non-transitory storage medium storing instructions for performing operations including: An apparatus comprising:

18. the at least one null subcarrier value of the first signal follows the at least one non-null subcarrier value of the first signal; the at least one null subcarrier value of the second signal precedes the at least one non-null subcarrier value of the second signal; and combining the first signal and the second signal into the single signal includes using the at least one non-null subcarrier value of the first signal as a leading subcarrier value of the single signal, and using the at least one non-null subcarrier value of the second signal as a trailing subcarrier value of the single signal that follows all of the leading subcarrier values.

18. The apparatus of claim 17.

19. an error condition occurs when the at least one null subcarrier value of the first signal precedes the at least one non-null subcarrier value of the first signal and the at least one non-null subcarrier value of the second signal precedes the at least one null subcarrier value of the second signal; 18. The apparatus of claim 17.

20. the at least one non-null subcarrier value of the first signal overlaps with the at least one null subcarrier value of the second signal; and the at least one non-null subcarrier value of the second signal overlaps with the at least one null subcarrier value of the first signal; 20. Apparatus according to any one of claims 17 to 19.

21. the operations further include, after combining the first signal and the second signal into the single signal, applying an inverse fast Fourier transform ("IFFT") or fast Fourier transform ("FFT") process to the single signal.

21. Apparatus according to any one of claims 17 to 20.

22. before said operation of combining said first signal and said second signal into said single signal: applying an inverse fast Fourier transform ("IFFT") or fast Fourier transform ("FFT") process to the first signal; and applying IFFT or FFT processing to the second signal.

21. Apparatus according to any one of claims 17 to 20.

23. the single signal reflects a bandwidth that is not one of the plurality of fixed operating bandwidths defined for the cellular network; 23. Apparatus according to any one of claims 17 to 22.

24. the operations further include performing a handshake between the first communication device and the second communication device establishing an understanding that the combining will be performed at a later time.

24. Apparatus according to any one of claims 17 to 23.

25. the operations further include detecting the subcarrier overlap using digital domain IQ data transmitted in the frequency domain of each of the first signal and the second signal, and using symbol duration transmitted in the time domain of each of the first signal and the second signal; wherein: the detecting facilitates the combining of the first signal and the second signal into the single signal.

25. Apparatus according to any one of claims 17 to 24.

26. one of the first communication device and the second communication device includes a distributed unit, and the other of the first communication device and the second communication device includes a radio unit; 26. The method of any one of claims 17 to 25.

27. the first communication device receiving the first signal and the second signal includes the distribution unit, and the second communication device includes the radio unit such that the communication is an uplink communication; 27. The apparatus of claim 26.

28. the first communication device receiving the first signal and the second signal includes the radio unit, and the second communication device includes the distributed unit such that the communication is a downlink communication; 27. The apparatus of claim 26.

29. the first communication device performs the combining; 27. The apparatus of claim 26.

30. the cellular network is a 3rd Generation Partnership Project ("3GPP") Long Term Evolution ("LTE") network; 30. Apparatus according to any one of claims 17 to 29.

31. The cellular network is a 5G network.

30. Apparatus according to any one of claims 17 to 29.

32. the single signal reflects a bandwidth that is not one of the plurality of fixed operating bandwidths defined for the network; 32. Apparatus according to claim 30 or 31.

33. at least one non-transitory storage medium, that when executed by at least one processor, causes the at least one processor to: receiving, at a first communication device in a cellular network, from a second communication device in the cellular network, a first signal in a first fixed operating bandwidth of a plurality of fixed operating bandwidths defined for the cellular network and a second signal in a second fixed operating bandwidth of the plurality of fixed operating bandwidths defined for the cellular network, wherein the first signal and the second signal have subcarrier overlap, the first signal includes at least one null subcarrier value and at least one non-null subcarrier value, and the second signal includes at least one null subcarrier value and at least one non-null subcarrier value; and combining the first signal and the second signal into a single signal that does not include the at least one null subcarrier value of the first signal and that does not include the at least one null subcarrier value of the second signal; A storage medium storing instructions for performing operations including:

34. the at least one null subcarrier value of the first signal follows the at least one non-null subcarrier value of the first signal; the at least one null subcarrier value of the second signal precedes the at least one non-null subcarrier value of the second signal; and combining the first signal and the second signal into the single signal includes using the at least one non-null subcarrier value of the first signal as a leading subcarrier value of the single signal, and using the at least one non-null subcarrier value of the second signal as a trailing subcarrier value of the single signal that follows all of the leading subcarrier values.

34. The storage medium of claim 33.

35. an error condition occurs when the at least one null subcarrier value of the first signal precedes the at least one non-null subcarrier value of the first signal and the at least one non-null subcarrier value of the second signal precedes the at least one null subcarrier value of the second signal; 34. The storage medium of claim 33.

36. the at least one non-null subcarrier value of the first signal overlaps with the at least one null subcarrier value of the second signal; and the at least one non-null subcarrier value of the second signal overlaps with the at least one null subcarrier value of the first signal; 36. A storage medium according to any one of claims 33 to 35.

37. the operations further include, after combining the first signal and the second signal into the single signal, applying an inverse fast Fourier transform ("IFFT") or fast Fourier transform ("FFT") process to the single signal.

37. A storage medium according to any one of claims 33 to 36.

38. before said operation of combining said first signal and said second signal into said single signal: applying an inverse fast Fourier transform ("IFFT") or fast Fourier transform ("FFT") process to the first signal; and applying IFFT or FFT processing to the second signal.

38. A storage medium according to any one of claims 33 to 37.

39. the single signal reflects a bandwidth that is not one of the plurality of fixed operating bandwidths defined for the cellular network; 39. A storage medium according to any one of claims 33 to 38.

40. the operations further include performing a handshake between the first communication device and the second communication device establishing an understanding that the coupling will be performed at a later time.

40. A storage medium according to any one of claims 33 to 39.

41. the operations further include detecting the subcarrier overlap using digital domain IQ data transmitted in the frequency domain of each of the first signal and the second signal, and using symbol duration transmitted in the time domain of each of the first signal and the second signal; wherein: the detecting facilitates the combining of the first signal and the second signal into the single signal.

41. A storage medium according to any one of claims 33 to 40.

42. one of the first communication device and the second communication device includes a distributed unit, and the other of the first communication device and the second communication device includes a radio unit; 42. A storage medium according to any one of claims 33 to 41.

43. the first communication device receiving the first signal and the second signal includes the distribution unit, and the second communication device includes the radio unit such that the communication is an uplink communication; 43. The storage medium of claim 42.

44. the first communication device receiving the first signal and the second signal includes the radio unit, and the second communication device includes the distributed unit such that the communication is a downlink communication; 43. The storage medium of claim 42.

45. the first communication device performs the combining; 43. The storage medium of claim 42.

46. the cellular network is a 3rd Generation Partnership Project ("3GPP") Long Term Evolution (LTE) network; 46. ​​A storage medium according to any one of claims 33 to 45.

47. The cellular network is a 5G network.

46. ​​A storage medium according to any one of claims 33 to 45.

48. the single signal reflects a bandwidth that is not one of the plurality of fixed operating bandwidths defined for the network; 48. A storage medium according to claim 46 or 47.

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