PRACH processing for O-RU

Abstract

The O-RU may: receive a PRACH preamble and a PUSCH within multiple symbols of a slot, the PRACH and the PUSCH having different parameter designs. The O-RU may: filter the PUSCH CP for each symbol of the PRACH preamble using an FFT window extending from the end of the PUSCH CP within the symbol to the end of the symbol; and perform an FFT on each FFT window for each symbol of the PRACH preamble. The O-RU may: extract I / Q data corresponding to the PRACH preamble in the frequency domain, adjust the phase shift of the extracted I / Q data to generate I / Q data for the PRACH preamble, the phase shift accounting for the shift of each FFT window in the time domain compared to the FFT window of the PRACH preamble with the PRACH CP filtered out, and transmit the I / Q data for the PRACH preamble to the O-DU.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. patent application No. 17 / 087,499, filed on November 2, 2020, entitled “PRACH PROCESSING FOR O-RU,” which is expressly incorporated herein by reference in its entirety. background Technical Field

[0004] The present disclosure relates generally to communication systems, and more particularly to physical random access channel (PRACH) processing for an open radio access network (O-RAN) radio unit (O-RU).

[0005] introduction

[0006] Wireless communication systems are widely deployed to provide a variety of telecommunication services, such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources. Examples of such multiple-access technologies include code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division multiple access (OFDMA), single-carrier frequency division multiple access (SC-FDMA), and time division synchronous code division multiple access (TD-SCDMA).

[0007] These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate at a city, country, region, and even global level. An example telecommunication standard is 5G New Radio (NR). 5G NR is part of the continuous mobile broadband evolution promulgated by the Third Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with the Internet of Things (IoT)) and other requirements. 5G NR includes services associated with enhanced mobile broadband (eMBB), massive machine type communications (mMTC), and ultra-reliable low latency communications (URLLC). Some aspects of 5G NR may be based on the 4G Long Term Evolution (LTE) standard. There is a need for further improvements to 5G NR technology. These improvements may also be applicable to other multiple access technologies and telecommunication standards that employ these technologies.

[0008] Overview

[0009] The following is a brief summary of one or more aspects to provide a basic understanding of such aspects. This summary is not an exhaustive overview of all conceivable aspects and is neither intended to identify key or critical elements of all aspects nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

[0010] In one aspect of the present disclosure, a method, computer-readable medium, and apparatus are provided. An O-RU may receive a PRACH preamble and a physical uplink shared channel (PUSCH) within multiple symbols of a slot, the PRACH and the PUSCH having different parameter designs. The O-RU may: filter a PUSCH cyclic prefix (CP) for each symbol of the PRACH preamble using an FFT window extending from the end of the PUSCH CP within the symbol to the end of the symbol; and perform an FFT within each FFT window for each symbol of the PRACH preamble. The O-RU may extract in-phase and quadrature (I / Q) data corresponding to the PRACH preamble in the frequency domain; adjust a phase shift of the extracted I / Q data to generate I / Q data for the PRACH preamble, the phase shift accounting for a shift of each FFT window in the time domain compared to the FFT window of the PRACH preamble with the PRACH CP filtered out; and send the I / Q data for the PRACH preamble to an O-RAN distribution unit (O-DU).

[0011] To accomplish the foregoing and related ends, one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and accompanying drawings set forth in detail certain illustrative features of the one or more aspects. However, these features are indicative of but a few of the various ways in which the principles of the various aspects may be employed, and this description is intended to encompass all such aspects and their equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a diagram illustrating an example of a wireless communication system and an access network.

[0014] Figure 2A is a diagram illustrating an example of a first frame according to various aspects of the present disclosure.

[0015] Figure 2B is a diagram illustrating an example of DL channels within a subframe according to various aspects of the present disclosure.

[0016] Figure 2C is a diagram illustrating an example of a second frame according to various aspects of the present disclosure.

[0017] Figure 2Dis a diagram illustrating an example of UL channels within a subframe according to various aspects of the present disclosure.

[0018] Figure 3 is a diagram illustrating an example of a base station and a user equipment (UE) in an access network.

[0019] Figure 4 An example of processing the PRACH for wireless communications is illustrated.

[0020] Figure 5 An example of processing the PRACH for wireless communications is illustrated.

[0021] Figure 6 An example of processing the PRACH for wireless communications is illustrated.

[0022] Figure 7 It is a call flow diagram for wireless communication.

[0023] Figure 8 is a flow chart of a wireless communication method.

[0024] Figure 9 is a diagram illustrating an example of a hardware implementation for an example device.

[0025] Detailed description

[0026] The detailed description set forth below in conjunction with the accompanying drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. This detailed description includes specific details to provide a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form to avoid overstating such concepts.

[0027] Several aspects of telecommunications systems will now be presented with reference to various apparatus and methods. These apparatus and methods are described in the following detailed description and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively, "elements"). These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system.

[0028] As an example, an element, or any part of an element, or any combination of elements can be implemented as a "processing system" comprising one or more processors. Examples of processors include: a microprocessor, a microcontroller, a graphics processing unit (GPU), a central processing unit (CPU), an application processor, a digital signal processor (DSP), a reduced instruction set computing (RISC) processor, a system on a chip (SoC), a baseband processor, a field programmable gate array (FPGA), a programmable logic device (PLD), a state machine, a gating logic, a discrete hardware circuit, and other suitable hardware configured to perform the various functionalities described throughout this disclosure. One or more processors in a processing system can execute software. Software should be broadly interpreted to mean instructions, instruction sets, codes, code segments, program codes, programs, subroutines, software components, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., whether it is described in software, firmware, middleware, microcode, hardware description language, or other terms.

[0029] Accordingly, in one or more example embodiments, the functions described can be implemented in hardware, software, or any combination thereof. If implemented in software, each function can be stored or encoded as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media. Storage media can be any available medium that can be accessed by a computer. As an example and not limitation, such computer-readable media may include random access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (EEPROM), optical disk storage, magnetic disk storage, other magnetic storage devices, a combination of the above-mentioned types of computer-readable media, or any other medium that can be used to store computer-accessible instructions or data structure forms of computer-executable code.

[0030] Figure 1 1 is a diagram illustrating an example of a wireless communication system and access network 100. The wireless communication system (also known as a wireless wide area network (WWAN)) includes a base station 102, a UE 104, an evolved packet core (EPC) 160, and another core network 190 (e.g., a 5G core (5GC)). The base station 102 may include a macro cell (a high-power cellular base station) and / or a small cell (a low-power cellular base station). A macro cell includes a base station. Small cells include femto cells, pico cells, and micro cells.

[0031] Base stations 102 configured for 4G LTE (collectively referred to as the Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN)) can interface with the EPC 160 via a first backhaul link 132 (e.g., an S1 interface). Base stations 102 configured for 5G NR (collectively referred to as the Next Generation RAN (NG-RAN)) can interface with the core network 190 via a second backhaul link 184. Among other functions, the base stations 102 can perform one or more of the following: delivery of user data, radio channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection establishment and release, load balancing, distribution of non-access stratum (NAS) messages, NAS node selection, synchronization, radio access network (RAN) sharing, multimedia broadcast multicast service (MBMS), subscriber and equipment tracking, RAN information management (RIM), paging, positioning, and delivery of alert messages. The base stations 102 can communicate with each other directly or indirectly (eg, through the EPC 160 or the core network 190) over a third backhaul link 134 (eg, an X2 interface). The first backhaul link 132, the second backhaul link 184, and the third backhaul link 134 can be wired or wireless.

[0032] Base stations 102 can communicate wirelessly with UEs 104. Each base station 102 can provide communication coverage for a respective geographic coverage area 110. There may be overlapping geographic coverage areas 110. For example, a small cell 102′ can have a coverage area 110′ that overlaps with the coverage area 110 of one or more macro base stations 102. A network that includes both small cells and macro cells can be referred to as a heterogeneous network. A heterogeneous network can also include a home evolved Node B (eNB) (HeNB), which can provide service to a restricted group known as a closed subscriber group (CSG). The communication link 120 between the base station 102 and the UE 104 can include uplink (UL) (also known as reverse link) transmissions from the UE 104 to the base station 102 and / or downlink (DL) (also known as forward link) transmissions from the base station 102 to the UE 104. The communication link 120 can utilize multiple-input multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and / or transmit diversity. These communication links may be over one or more carriers. For each carrier allocated in the carrier aggregation for a total of up to Yx MHz (x component carriers) for transmission in each direction, the base station 102 / UE 104 may use spectrum with a bandwidth of up to Y MHz (e.g., 5, 10, 15, 20, 100, 400 MHz, etc.). These carriers may or may not be adjacent to each other. The allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated to DL compared to UL). The component carriers may include a primary component carrier and one or more secondary component carriers. The primary component carrier may be referred to as a primary cell (PCell), and the secondary component carriers may be referred to as secondary cells (SCells).

[0033] Some UEs 104 may communicate with each other using device-to-device (D2D) communication links 158. The D2D communication links 158 may use DL / UL WWAN spectrum. The D2D communication links 158 may use one or more sidelink channels, such as a physical sidelink broadcast channel (PSBCH), a physical sidelink discovery channel (PSDCH), a physical sidelink shared channel (PSSCH), and a physical sidelink control channel (PSCCH). D2D communication may be accomplished through various wireless D2D communication systems, such as, for example, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, LTE, or NR.

[0034] The wireless communication system may further include a Wi-Fi access point (AP) 150 in communication with a Wi-Fi station (STA) 152 via a communication link 154, e.g., in the 5 GHz unlicensed spectrum. When communicating in the unlicensed spectrum, the STA 152 / AP 150 may perform a clear channel assessment (CCA) to determine whether the channel is available prior to communication.

[0035] Small cell 102′ can operate in licensed and / or unlicensed spectrum. When operating in unlicensed spectrum, small cell 102′ can adopt NR and use the same unlicensed spectrum (e.g., 5 GHz, etc.) used by Wi-Fi AP 150. Small cell 102′ adopting NR in unlicensed spectrum can improve access network coverage and / or increase access network capacity.

[0036] The electromagnetic spectrum is typically subdivided into various classes, bands, channels, etc. based on frequency / wavelength. In 5G NR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz–7.125 GHz) and FR2 (24.25 GHz–52.6 GHz). Frequencies between FR1 and FR2 are typically referred to as mid-band frequencies. Although a portion of FR1 is greater than 6 GHz, FR1 is often (interchangeably) referred to as the “sub-6 GHz” band in various documents and articles. Similar naming issues sometimes arise with respect to FR2, which is often (interchangeably) referred to as the “millimeter wave” band in various documents and articles, although it is different from the extremely high frequency (EHF) band (30 GHz–300 GHz) identified as the “millimeter wave” band by the International Telecommunication Union (ITU).

[0037] In view of the above aspects, unless otherwise specified, it should be understood that the term sub-6 GHz, etc., if used herein, can broadly refer to frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. In addition, unless otherwise specified, it should be understood that the term "millimeter wave", etc., if used herein, can broadly refer to frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies.

[0038] Whether a small cell 102' or a macro cell (e.g., a macro base station), base station 102 may include and / or be referred to as an eNB, a g Node B (gNB), or another type of base station. Some base stations, such as gNB 180, may operate in the traditional sub-6 GHz spectrum, in millimeter wave frequencies, and / or near millimeter wave frequencies to communicate with UE 104. When gNB 180 operates in millimeter wave frequencies or near millimeter wave frequencies, gNB 180 may be referred to as a millimeter wave base station. Millimeter wave base station 180 may utilize beamforming 182 with UE 104 to compensate for path loss and short range. Base station 180 and UE 104 may each include multiple antennas, such as antenna elements, antenna panels, and / or antenna arrays, to facilitate beamforming.

[0039] Base station 180 may transmit beamformed signals in one or more transmit directions 182′ to UE 104. UE 104 may receive beamformed signals from base station 180 in one or more receive directions 182″. UE 104 may also transmit beamformed signals to base station 180 in one or more transmit directions. Base station 180 may receive beamformed signals from UE 104 in one or more receive directions. Base station 180 / UE 104 may perform beam training to determine the best receive direction and transmit direction for each of base station 180 / UE 104. The transmit direction and receive direction of base station 180 may be the same or different. The transmit direction and receive direction of UE 104 may be the same or different.

[0040] EPC 160 may include a Mobility Management Entity (MME) 162, other MMEs 164, a Serving Gateway 166, a Multimedia Broadcast Multicast Service (MBMS) Gateway 168, a Broadcast Multicast Service Center (BM-SC) 170, and a Packet Data Network (PDN) Gateway 172. MME 162 may be in communication with a Home Subscriber Server (HSS) 174. MME 162 is a control node that handles signaling between UE 104 and EPC 160. Generally speaking, MME 162 provides bearer and connection management. All user Internet Protocol (IP) packets are passed through Serving Gateway 166, which itself is connected to PDN Gateway 172. PDN Gateway 172 provides UE IP address allocation and other functions. PDN Gateway 172 and BM-SC 170 are connected to IP Services 176. IP Services 176 may include the Internet, an intranet, an IP Multimedia Subsystem (IMS), PS streaming services, and / or other IP services. The BM-SC 170 can provide functionality for MBMS user service provisioning and delivery. The BM-SC 170 can serve as the entry point for content providers' MBMS transmissions, authorize and initiate MBMS bearer services within the Public Land Mobile Network (PLMN), and schedule MBMS transmissions. The MBMS Gateway 168 can be used to distribute MBMS traffic to base stations 102 within the Multicast Broadcast Single Frequency Network (MBSFN) area broadcasting a specific service, and can be responsible for session management (start / stop) and collecting eMBMS-related charging information.

[0041] The core network 190 may include an access and mobility management function (AMF) 192, other AMFs 193, a session management function (SMF) 194, and a user plane function (UPF) 195. The AMF 192 may be in communication with a unified data management (UDM) 196. The AMF 192 is a control node that handles signaling between the UE 104 and the core network 190. Generally speaking, the AMF 192 provides QoS flow and session management. All user Internet Protocol (IP) packets are passed through the UPF 195. The UPF 195 provides UE IP address allocation and other functions. The UPF 195 is connected to the IP services 197. The IP services 197 may include the Internet, an intranet, an IP multimedia subsystem (IMS), packet switched (PS) streaming (PSS) services, and / or other IP services.

[0042] A base station may include and / or be referred to as a gNB, a Node B, an eNB, an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS), an extended service set (ESS), a transmit reception point (TRP), or some other suitable terminology. Base station 102 provides an access point for UE 104 to EPC 160 or core network 190. Examples of UE 104 include a cellular phone, a smartphone, a Session Initiation Protocol (SIP) phone, a laptop, a personal digital assistant (PDA), a satellite radio, a global positioning system, a multimedia device, a video device, a digital audio player (e.g., an MP3 player), a camera, a game console, a tablet device, a smart device, a wearable device, a vehicle, an electric meter, a gas pump, a large or small kitchen appliance, a healthcare device, an implant, a sensor / actuator, a display, or any other similarly functional device. Some UEs 104 may be referred to as IoT devices (e.g., a parking meter, a gas pump, an oven, a vehicle, a heart monitor, etc.). UE 104 may also be referred to as a station, a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communication device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology.

[0043] Reference again Figure 1 In certain aspects, the base station 180 may include an O-RU including a PRACH processing component 198 configured to: receive a PRACH preamble and a PUSCH within a plurality of symbols of a slot, the PRACH and the PUSCH having different parameter designs; filter the PUSCH CP for each symbol of the PRACH preamble using an FFT window extending from an end of the PUSCH CP within the symbol to an end of the symbol; and perform an FFT per FFT window for each symbol of the PRACH preamble. The PRACH processing component 198 can be further configured to: extract in-phase and quadrature (I / Q) data corresponding to the PRACH preamble in the frequency domain; adjust the phase shift of the extracted I / Q data to generate I / Q data for the PRACH preamble, the phase shift accounting for the shift of each FFT window in the time domain compared to the FFT window of the PRACH preamble with the PRACH CP filtered out; and send the I / Q data for the PRACH preamble to the O-DU. Although the following description may focus on 5G NR, the concepts described herein can be applied to other similar fields, such as LTE, LTE-A, CDMA, GSM, and other wireless technologies.

[0044] Figure 2Ais a diagram 200 illustrating an example of a first subframe within a 5G NR frame structure. Figure 2B is a diagram 230 illustrating an example of DL channels within a 5G NR subframe. Figure 2C is a diagram 250 illustrating an example of a second subframe within a 5G NR frame structure. Figure 2D FIG28 is a diagram illustrating an example of UL channels within a 5G NR subframe. The 5G NR frame structure may be frequency division duplex (FDD), where for a particular set of subcarriers (carrier system bandwidth), subframes within that subcarrier set are dedicated to either DL or UL; or time division duplex (TDD), where for a particular set of subcarriers (carrier system bandwidth), subframes within that subcarrier set are dedicated to both DL and UL. Figure 2A 、 2C In the example provided, the 5G NR frame structure is assumed to be TDD, where subframe 4 is configured with slot format 28 (mostly DL) and subframe 3 is configured with slot format 1 (all UL), where D is DL, U is UL, and F is for flexible use between DL / UL. Although subframes 3 and 4 are shown as having slot formats 1 and 28, respectively, any particular subframe can be configured with any of the various available slot formats 0-61. Slot formats 0 and 1 are full DL and full UL, respectively. Other slot formats 2-61 include a mix of DL, UL, and flexible symbols. The UE is configured with a slot format (dynamically configured through DL control information (DCI) or semi-statically / statically configured through radio resource control (RRC) signaling) via the received slot format indicator (SFI). Note that the following description also applies to the 5G NR frame structure for TDD.

[0045] Other wireless communication technologies may have different frame structures and / or different channels. A frame (10ms) may be divided into 10 equally sized subframes (1ms). Each subframe may include one or more time slots. A subframe may also include mini-slots, which may include 7, 4, or 2 symbols. Each time slot may include 7 or 14 symbols, depending on the time slot configuration. For time slot configuration 0, each time slot may include 14 symbols, while for time slot configuration 1, each time slot may include 7 symbols. The symbols on the DL may be cyclic prefix (CP) OFDM (CP-OFDM) symbols. The symbols on the UL may be CP-OFDM symbols (for high throughput scenarios) or discrete Fourier transform (DFT) spread OFDM (DFT-s-OFDM) symbols (also known as single carrier frequency division multiple access (SC-FDMA) symbols) (for power-limited scenarios; limited to single stream transmission). The number of time slots within a subframe is based on the time slot configuration and parameter design. For slot configuration 0, different parameter designs μ of 0 to 4 allow 1, 2, 4, 8, and 16 slots per subframe, respectively. For slot configuration 1, different parameter designs 0 to 2 allow 2, 4, and 8 slots per subframe, respectively. Accordingly, for slot configuration 0 and parameter design μ, there are 14 symbols per slot and 2 per subframe. μ The subcarrier spacing and symbol length / duration vary depending on the parameter design. The subcarrier spacing can be equal to 2 μ *15kHz, where μ is parameter design 0 to 4. Thus, parameter design μ=0 has a subcarrier spacing of 15kHz, while parameter design μ=4 has a subcarrier spacing of 240kHz. The symbol length / duration is inversely related to the subcarrier spacing. Figures 2A to 2D An example is provided for slot configuration 0 with 14 symbols per slot and parameter design μ=2 with 4 slots per subframe. The slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is approximately 16.67 μs. Within a frame set, there may be one or more different bandwidth parts (BWPs) that are frequency-division multiplexed (see Figure 2B ). Each BWP may have a specific parameter design.

[0046] A resource grid can be used to represent the frame structure. Each slot includes a resource block (RB) (also called a physical RB (PRB)) that extends over 12 consecutive subcarriers. The resource grid is divided into multiple resource elements (REs). The number of bits carried by each RE depends on the modulation scheme.

[0047] like Figure 2AAs illustrated in

[15] , some REs carry reference (pilot) signals (RS) for the UE. The RSs may include a demodulation RS (DM-RS) (indicated as R for one specific configuration, but other DM-RS configurations are possible) and a channel state information reference signal (CSI-RS) for channel estimation at the UE. The RSs may also include a beam measurement RS (BRS), a beam refinement RS (BRRS), and a phase tracking RS (PT-RS).

[0048] Figure 2B Examples of various DL channels within a subframe of a frame are illustrated. The physical downlink control channel (PDCCH) carries DCI within one or more control channel elements (CCEs) (e.g., 1, 2, 4, 8, or 16 CCEs), each CCE comprising 6 RE groups (REGs), each REG comprising 12 consecutive REs within an OFDM symbol of the RB. The PDCCH within a BWP may be referred to as a control resource set (CORESET). The UE is configured to monitor PDCCH candidates in a PDCCH search space (e.g., a common search space, a UE-specific search space) during a PDCCH monitoring opportunity on the CORESET, where the PDCCH candidates have different DCI formats and different aggregation levels. Additional BWPs may be located at higher and / or lower frequencies across the channel bandwidth. The primary synchronization signal (PSS) may be within symbol 2 of a particular subframe of the frame. The PSS is used by the UE 104 to determine subframe / symbol timing and physical layer identity. The secondary synchronization signal (SSS) may be within symbol 4 of a particular subframe of the frame. The SSS is used by the UE to determine the physical layer cell identity group number and radio frame timing. Based on the physical layer identity and the physical layer cell identity group number, the UE can determine the physical cell identifier (PCI). Based on the PCI, the UE can determine the position of the aforementioned DM-RS. The physical broadcast channel (PBCH) carrying the master information block (MIB) can be logically grouped with the PSS and SSS to form a synchronization signal (SS) / PBCH block (also referred to as an SS block (SSB)). The MIB provides the number of RBs in the system bandwidth and the system frame number (SFN). The physical downlink shared channel (PDSCH) carries user data, broadcast system information not transmitted over the PBCH (such as the system information block (SIB)), and paging messages.

[0049] As in Figure 2CAs illustrated in FIG, some REs carry DM-RSs for channel estimation at the base station (indicated as R for one specific configuration, but other DM-RS configurations are possible). The UE may transmit DM-RSs for the physical uplink control channel (PUCCH) and DM-RSs for the physical uplink shared channel (PUSCH). The PUSCH DM-RS may be transmitted in the first or first two symbols of the PUSCH. The PUCCH DM-RS may be transmitted in different configurations depending on whether a short PUCCH or a long PUCCH is transmitted and on the specific PUCCH format used. The UE may transmit a sounding reference signal (SRS). The SRS may be transmitted in the last symbol of the subframe. The SRS may have a comb-tooth structure, and the UE may transmit the SRS on one of the comb teeth. The SRS may be used by the base station for channel quality estimation to enable frequency-dependent scheduling on the UL.

[0050] Figure 2D Illustrated are examples of various UL channels within a subframe of a frame. The PUCCH may be located at the position indicated in one configuration. The PUCCH carries uplink control information (UCI), such as scheduling requests, channel quality indicator (CQI), precoding matrix indicator (PMI), rank indicator (RI), and hybrid automatic repeat request (HARQ) ACK / NACK feedback. The PUSCH carries data and may additionally be used to carry a buffer status report (BSR), a power headroom report (PHR), and / or UCI.

[0051] Figure 33 is a block diagram of a base station 310 and a UE 350 in communication in an access network. In the DL, IP packets from the EPC 160 may be provided to the controller / processor 375. The controller / processor 375 implements layer 3 and layer 2 functionality. Layer 3 includes the radio resource control (RRC) layer, and layer 2 includes the service data adaptation protocol (SDAP) layer, the packet data convergence protocol (PDCP) layer, the radio link control (RLC) layer, and the medium access control (MAC) layer. The controller / processor 375 provides RRC layer functionality associated with broadcasting of system information (e.g., MIB, SIB), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-radio access technology (RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality associated with header compression / decompression, security (ciphering, deciphering, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with delivery of upper layer packet data units (PDUs), error correction through ARQ, concatenation, segmentation and reassembly of RLC service data units (SDUs), resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

[0052] The transmit (TX) processor 316 and the receive (RX) processor 370 implement Layer 1 functionality associated with various signal processing functions. Layer 1, including the physical (PHY) layer, may include error detection on the transport channel, forward error correction (FEC) coding / decoding of the transport channel, interleaving, rate matching, mapping onto the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. The TX processor 316 handles the mapping to the signal constellation based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-phase shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The decoded and modulated symbols may then be split into parallel streams. Each stream may then be mapped to an OFDM subcarrier, multiplexed with a reference signal (e.g., a pilot) in the time and / or frequency domain, and then combined together using an inverse fast Fourier transform (IFFT) to produce a physical channel carrying a time-domain OFDM symbol stream. The OFDM stream is spatially precoded to generate multiple spatial streams. Channel estimates from a channel estimator 374 may be used to determine the coding and modulation schemes and for spatial processing. The channel estimates may be derived from a reference signal and / or channel condition feedback transmitted by the UE 350. Each spatial stream may then be provided to a different antenna 320 via a separate transmitter 318TX. Each transmitter 318TX may modulate an RF carrier with a corresponding spatial stream for transmission.

[0053] At the UE 350, each receiver 354RX receives a signal via its respective antenna 352. Each receiver 354RX recovers the information modulated onto the RF carrier and provides the information to a receive (RX) processor 356. The TX processor 368 and the RX processor 356 implement layer 1 functionality associated with various signal processing functions. The RX processor 356 performs spatial processing on the information to recover any spatial streams destined for the UE 350. If there are multiple spatial streams destined for the UE 350, they may be combined by the RX processor 356 into a single OFDM symbol stream. The RX processor 356 then converts the OFDM symbol stream from the time domain to the frequency domain using a fast Fourier transform (FFT). The frequency domain signal includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, as well as the reference signal, are recovered and demodulated by determining the signal constellation point most likely transmitted by the base station 310. These soft decisions may be based on channel estimates calculated by the channel estimator 358. These soft decisions are then decoded and deinterleaved to recover the data and control signals originally transmitted on the physical channel by the base station 310. These data and control signals are then provided to the controller / processor 359, which implements layer 3 and layer 2 functionality.

[0054] The controller / processor 359 may be associated with a memory 360 that stores program codes and data. The memory 360 may be referred to as a computer-readable medium. In the UL, the controller / processor 359 provides demultiplexing between transport and logical channels, packet reassembly, cipher decoding, header decompression, and control signal processing to recover IP packets from the EPC 160. The controller / processor 359 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operations.

[0055] Similar to the functionality described in conjunction with DL transmissions performed by the base station 310, the controller / processor 359 provides RRC layer functionality associated with system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting; PDCP layer functionality associated with header compression / decompression and security (ciphering, deciphering, integrity protection, integrity verification); RLC layer functionality associated with delivery of upper layer PDUs, error correction through ARQ, concatenation, segmentation, and reassembly of RLC SDUs, resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing MAC SDUs onto TBs, demultiplexing MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

[0056] Channel estimates derived by a channel estimator 358 from a reference signal or feedback transmitted by the base station 310 may be used by a TX processor 368 to select the appropriate coding and modulation scheme, and to facilitate spatial processing. The spatial streams generated by the TX processor 368 may be provided to different antennas 352 via separate transmitters 354TX. Each transmitter 354TX may modulate an RF carrier with a corresponding spatial stream for transmission.

[0057] UL transmissions are processed at the base station 310 in a manner similar to that described in conjunction with the receiver functionality at the UE 350. Each receiver 318RX receives a signal through its respective antenna 320. Each receiver 318RX recovers information modulated onto an RF carrier and provides the information to an RX processor 370.

[0058] The controller / processor 375 may be associated with a memory 376 that stores program codes and data. The memory 376 may be referred to as a computer-readable medium. In the UL, the controller / processor 375 provides demultiplexing between transport and logical channels, packet reassembly, cipher decoding, header decompression, and control signal processing to recover IP packets from the UE 350. The IP packets from the controller / processor 375 may be provided to the EPC 160. The controller / processor 375 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operations.

[0059] At least one of the TX processor 316, the RX processor 370, and the controller / processor 375 may be configured to perform operations related to Figure 1 The 198 combines all aspects.

[0060] O-RAN may provide standardization of radio interfaces to facilitate interoperability between component radio equipment. A base station of O-RAN may include an O-RAN distributed unit (O-DU) and an O-RAN radio unit (O-RU), with lower layer functions split between the O-DU and the O-RU based on a lower layer function split. That is, the O-DU may refer to a logical node configured to host an RLC layer, a MAC layer, and a high PHY layer based on a lower layer function split. The O-RU may refer to a logical node configured to host a low PHY layer and RF processing based on a lower layer function split. The O-RAN may include an open outbound interface between the O-RU and the O-DU, and the open outbound interface may include a control user synchronization (CUS) plane and a management (M) plane.

[0061] The C-plane is the control plane, which may specifically refer to the real-time control between the O-DU and the O-RU. The U-plane is the user plane, which may refer to the IQ sample data transmitted between the O-DU and the O-RU. The S-plane is the synchronization plane, which may refer to the traffic between the O-RU or the O-DU and the synchronization controller. The M-plane is the management plane, which may refer to the non-real-time management operation between the O-DU and the O-RU. The segment type 3 message of the C-plane may specify the scheduling and beamforming command frame format for PRACH and hybrid parameter design. The segment type 3 C-plane message may include parameters such as CP length and / or time offset. The O-RU may receive the segment type 3 C-plane message, extract the PRACH CP, and transmit the I / Q data of the PRACH preamble with the PRACH CP removed to the O-DU.

[0062] In some aspects, the O-RU may not support hybrid parameter design to reduce the cost and complexity of the O-RU. In response to a Segment Type 3 message, the O-RU that does not support hybrid parameter design may perform two separate FFTs for UL data when PUSCH and PRACH are in the same time slot because the PRACH CP is different from the PUSCH CP. Various embodiments of the present disclosure may provide a mechanism for the O-RU to use a single FFT to implement PRACH and PUSCH processing and send IQ data in a format such that the O-DU can receive IQ data from the O-RU regardless of the O-RU's implementation of PRACH processing.

[0063] Figure 4 An example of processing PRACH 400 for wireless communication is illustrated. The O-RU may receive a segment type 3 C-plane message for a PRACH preamble, and the message may instruct the O-RU on the PRACH start symbol and the physical resource blocks (PRBs) requested by the O-DU. For example, the PRACH preamble may include a PRACH CP and four (4) repetitions of the preamble sequence. According to option 1, based on the segment type 3 C-plane message, the O-RU may filter the PRACH preamble by removing the PRACH CP 402 and perform an FFT on each repetition of the preamble sequence. That is, the O-RU may perform FFTs on a first FFT window 404, a second FFT window 406, a third FFT window 408, and a fourth FFT window 410, each FFT window corresponding to four repetitions of the preamble sequence. However, when the O-RU does not support hybrid parameter design, the O-RU may perform two separate FFTs for PUSCH and PRACH because the PRACH CP may be different from the PUSCH CP.

[0064] According to Option 2A, instead of performing an FFT on each repetition of the preamble sequence of the signal with the PRACH CP removed as shown in Option 1, the O-RU may perform an FFT on each symbol of the PRACH preamble from which the PUSCH CP has been removed. That is, the O-RU may filter the PRACH preamble by removing the PUSCH CP 412 and perform an FFT on each symbol of the PRACH preamble from which the PUSCH CP has been removed. The O-RU may perform FFTs for a first FFT window 414, a second FFT window 416, a third FFT window 418, and a fourth FFT window 420, each corresponding to a symbol of the preamble sequence from which the PUSCH CP has been removed. The PUSCH CP may be configured via the M-plane as part of a capability exchange.

[0065] Based on the FFT results, the O-RU may extract I / Q data corresponding to the PRACH preamble in the frequency domain and adjust the phase shift of the extracted I / Q data per symbol to account for the shifted FFT window compared to the intended FFT window for the PRACH preamble. That is, since the first to fourth FFT windows 414, 416, 418, and 420 are shifted compared to the original first to fourth FFT windows 404, 406, 408, and 410, the O-RU may compensate for the shifted FFT window by adjusting the phase shift of the extracted I / Q data to account for the phase difference between the first to fourth FFT windows 414, 416, 418, and 420 and the original first to fourth FFT windows 404, 406, 408, and 410 of the PRACH preamble. The O-RU may send the I / Q data for the PRACH in the frequency domain to the O-DU.

[0066] According to Option 2A, the O-RU may perform one FFT for both PRACH and PUSCH. Thus, the O-RU may not utilize separate chains to process PRACH and PUSCH separately, and the cost, complexity, and power requirements of the O-RU may be reduced. Because the O-DU may be transparent to the processing of PRACH I / Q data in the O-RU (e.g., regardless of whether the O-RU follows Option 1 or Option 2A), the O-RU may perform a single FFT for both PRACH and PUSCH without any changes or impact to the O-RAN framework.

[0067] Figure 5 An example of processing a PRACH for wireless communication 500 is illustrated. In some aspects, a delay 530 greater than a PUSCH CP 512 and less than a PRACH CP 502 may be associated with a PRACH preamble, and at least a portion of the PRACH energy may be lost (i.e., energy loss 540) for a first FFT window corresponding to a first removed PRACH preamble symbol for the PUSCH CP.

[0068] The O-RU may receive a segment type 3 C-plane message for the PRACH preamble, and the message may instruct the O-RU on the PRACH start symbol and the physical resource blocks (PRBs) requested by the O-DU. For example, the PRACH preamble may include a PRACH CP and four (4) repetitions of the preamble sequence. According to option 1, based on the segment type 3 C-plane message, the O-RU may filter the PRACH preamble by removing the PRACH CP 502 and perform an FFT on each repetition of the preamble sequence. That is, the O-RU may perform FFTs for a first FFT window 504, a second FFT window 506, a third FFT window 508, and a fourth FFT window 510, each corresponding to four repetitions of the preamble sequence. However, when the O-RU may not support hybrid parameter design, the O-RU may perform two separate FFTs for PUSCH and PRACH because the PRACH CP may be different from the PUSCH CP. Likewise, option 1 may not account for the delay 530.

[0069] According to Option 2B, the O-RU may perform an FFT on each symbol of the PRACH preamble with the PUSCH CP removed. That is, the O-RU may filter the PRACH preamble by removing the PUSCH CP 512 and perform an FFT on each symbol of the PRACH preamble with the PUSCH CP removed. The O-RU may perform FFTs for a first FFT window 513, a second FFT window 516, a third FFT window 518, and a fourth FFT window 520, each corresponding to a symbol of the preamble sequence with the PUSCH CP removed. The PUSCH CP may be configured via the M-plane as part of a capability exchange. The O-RU may extract frequency-domain I / Q data corresponding to the PRACH preamble.

[0070] The O-RU may detect the delay 530 associated with the PRACH preamble by checking noise samples in the corresponding time domain by taking the inverse FFT (IFFT) of the tone of the first FFT window 513. The O-RU may also detect the delay by correlation with a reference PRACH CP or other means.

[0071] Once the O-RU determines the delay 530, the O-RU may remove the initial time domain samples equivalent to the estimated delay from the first symbol and obtain the initial TD samples (estimated delay - PUSCH CP) for the first symbol of the first FFT window (before removing the PUSCH CP). That is, the O-RU may shift the first FFT window 513 by the estimated delay 530 corresponding to the detected energy loss 540 to a shifted first FFT window 514. The O-RU may perform an FFT on each shifted first FFT window 514. For example, the shifted first FFT window 514 may span two symbols (e.g., symbol 0 and symbol 1).

[0072] The O-RU may adjust the phase shift of the extracted I / Q data per symbol to account for the shifted FFT window compared to the expected FFT window for the PRACH preamble to determine the I / Q data corresponding to the PRACH preamble in the frequency domain. That is, since the shifted first FFT window 514 and the second to fourth FFT windows 516, 518, and 520 are shifted compared to the original first to fourth FFT windows 504, 506, 508, and 510, the O-RU may compensate for the shifted FFT window by adjusting the phase shift of the extracted I / Q data to account for the phase difference between the shifted first FFT window 514 and the second to fourth FFT windows 516, 518, and 520 and the original first to fourth FFT windows 504, 506, 508, and 510 of the PRACH preamble. The O-RU may send the I / Q data for the PRACH in the frequency domain to the O-DU.

[0073] According to Option 2B, the O-RU may perform one FFT for both PRACH and PUSCH. Thus, the O-RU may not utilize separate chains to process PRACH and PUSCH separately, and the cost, complexity, and power specifications of the O-RU may be reduced. Since the O-DU may be transparent to the processing of PRACH I / Q data in the O-RU (e.g., regardless of whether the O-RU follows Option 1 or Option 2B), the O-RU may perform a single FFT for PRACH and PUSCH without any changes or impact to the O-RAN framework. In addition, the PRACH energy loss of the first FFT window of the PRACH may be minimized or reduced. Thus, the O-RU may increase the probability of detection for large delay scenarios.

[0074] Option 2B, on the other hand, includes additional IIFTs and FFTs. Specifically, Option 2B includes one (1) drop-point IFFT corresponding to the PRACH to detect or calculate the delay 530 based on the delay detection mechanism, and one (1) full-point FFT for the shifted first FFT window 514, which can be performed on the first symbol and the second symbol.

[0075] In some aspects, at least one advantage over proposal one may be a function of delay estimation accuracy.

[0076] Figure 6 An example of a PRACH 600 for processing wireless communications is illustrated. In some aspects, the O-RU may take Figure 56. A hybrid approach of Option 1 and Option 2B as described in

[15] . A delay 630 greater than the PUSCH CP 512 and less than the PRACH CP 602 may be associated with the PRACH preamble. According to Option 1, based on the Segment Type 3C message, the O-RU may filter the PRACH preamble by removing the PRACH CP 602 and perform an FFT on each repetition of the preamble sequence. That is, the O-RU may perform FFTs for the first FFT window 604, the second FFT window 606, the third FFT window 608, and the fourth FFT window 610, each corresponding to four repetitions of the preamble sequence. However, when the O-RU may not support hybrid parameter design, the O-RU may perform two separate FFTs for PUSCH and PRACH because the PRACH CP may be different from the PUSCH CP. Similarly, Option 1 may not account for the delay 630.

[0077] According to Option 2C, instead of performing an FFT on each repetition of the preamble sequence of the signal with the PRACH CP removed, the O-RU may perform an FFT on each symbol of the PRACH preamble with the PUSCH CP removed, except for the starting symbol (or first symbol) of the PRACH. The PUSCH CP may be configured via the M-plane as part of capability exchange. For the starting symbol of the PRACH, a CP equivalent to the PRACH CP may be removed to process the PRACH, and one FFT may be performed after taking samples from the PRACH starting symbol. That is, the O-RU may perform FFTs for a second FFT window 616, a third FFT window 618, and a fourth FFT window 620, each corresponding to a symbol of the preamble sequence with the PUSCH CP removed. For the first FFT window 614, the O-RU may shift the first FFT window 614 corresponding to the first symbol of the PRACH by the PRACH CP and perform an FFT on the first FFT window 614.

[0078] The O-RU can extract the I / Q data corresponding to the PRACH preamble in the frequency domain from the FFT results and adjust the phase shift of the extracted I / Q data for each symbol (except for the first symbol of the PRACH) to account for the shifted FFT window compared to the intended FFT window for the PRACH preamble. That is, since the second to fourth FFT windows 616, 618, and 620 are shifted compared to the original second to fourth FFT windows 606, 608, and 610, the O-RU can compensate for the shifted FFT window by adjusting the phase shift of the extracted I / Q data to account for the phase difference between the second to fourth FFT windows 616, 618, and 620 and the original second to fourth FFT windows 606, 608, and 610 of the PRACH preamble. Since the first FFT window 614 of the first symbol of the PRACH is shifted by the PRACH CP, the first FFT window 614 overlaps with the original first FFT window 604. The O-RU may send I / Q data of the PRACH in the frequency domain to the O-DU.

[0079] According to Option 2C, the O-RU may perform one FFT for PRACH and PUSCH together, except for the first symbol of PRACH. Therefore, the O-RU may not utilize separate chains to process PRACH and PUSCH separately, and the cost, complexity, and power specifications of the O-RU may be reduced. Since the O-DU may be transparent to the processing of PRACH I / Q data in the O-RU (e.g., regardless of whether the O-RU follows Option 1 or Option 2C), the O-RU may perform a single FFT for PRACH and PUSCH without any changes or impact to the O-RAN framework. In addition, the PRACH energy loss of the first FFT window of PRACH may be eliminated or reduced. Therefore, the O-RU may increase the detection probability for large delay scenarios. In addition, compared to Option 2B, the O-RU may not perform initial delay estimation.

[0080] However, Option 2C may utilize one full FFT compared to Proposal 1, and if the PRACH CP is close to the symbol length (e.g., PRACH format C2), the time-domain samples of the first FFT window and the second FFT window may almost completely overlap and thus may have reduced time diversity gain. (That is, Option 2C may be more feasible for other PRACH formats such as B2, B3, and / or B4).

[0081] Figure 7 7 is a call flow diagram 700 for wireless communication including an O-RU 700 and an O-DU 704 .

[0082] At 706, the O-RU 702 may receive a PRACH preamble and a PUSCH within multiple symbols of a slot, the PRACH and the PUSCH having different parameter designs, the PRACH preamble including a PRACH CP in the first symbol of the slot, and the PUSCH including a PUSCH CP in each symbol of the slot.

[0083] At 708, the O-RU 702 may filter the PUSCH CP for each symbol of the PRACH preamble using an FFT window extending from the end of the PUSCH CP within the symbol to the end of the symbol. A first FFT window for a first symbol may include a portion of the PRACH CP.

[0084] At 710, the O-RU 702 may shift a first FFT window corresponding to a first symbol of a PRACH by the PRACH CP in the time domain. The first FFT window of the first symbol includes a portion of the PRACH CP.

[0085] At 712, the O-RU 702 may perform an FFT per FFT window for each symbol of the PRACH preamble.

[0086] At 714, the O-RU 702 may extract I / Q data corresponding to the PRACH preamble in the frequency domain from the results of the FFT performed per FFT window for each symbol of the PRACH preamble.

[0087] At 716, the O-RU 702 may estimate a delay associated with the PRACH preamble. The delay associated with the PRACH preamble may be estimated by performing an IFFT on the extracted I / Q data of the first FFT window to check for time domain noise samples or by correlating with a reference PRACH preamble CP.

[0088] At 718, the O-RU 702 may shift the first FFT window corresponding to the first symbol of the PRACH preamble in the time domain by the estimated delay.The shifted first FFT window may span two symbols.

[0089] At 720, the O-RU 702 may perform an FFT on the shifted first FFT window.

[0090] At 722, the O-RU 702 may adjust a phase shift of the extracted I / Q data to account for a shift in the time domain of each FFT window compared to the FFT window of the PRACH preamble with the PRACH CP filtered out to generate I / Q data for the PRACH preamble.

[0091] At 724 , the O-RU 702 may send the I / Q data of the PRACH preamble to the O-DU 704 .

[0092] Figure 8 800 is a flow chart of a wireless communication method. The method may be performed by an O-RU of a base station (eg, base station 102 / 180; device 902).

[0093] At 806, the O-RU may receive a PRACH preamble and a PUSCH within multiple symbols of a slot, the PRACH and the PUSCH having different parameter designs (e.g., as at 706). The PRACH preamble includes a PRACH CP in the first symbol of the slot, and the PUSCH includes a PUSCH CP in each symbol of the slot. For example, 806 may be performed by PRACH processing component 940.

[0094] At 808, the O-RU 702 may filter the PUSCH CP for each symbol of the PRACH preamble using an FFT window that extends from the end of the PUSCH CP within the symbol to the end of the symbol (e.g., as at 708). The first FFT window for the first symbol may include a portion of the PRACH CP. For example, 808 may be performed by the PRACH processing component 940.

[0095] At 810, the O-RU may shift a first FFT window corresponding to a first symbol of the PRACH by the PRACH CP in the time domain (e.g., as at 710). The first FFT window of the first symbol includes a portion of the PRACH CP. For example, 810 may be performed by PRACH processing component 940.

[0096] At 812, the O-RU may perform an FFT per FFT window for each symbol of the PRACH preamble (e.g., as at 712). For example, 812 may be performed by PRACH processing component 940.

[0097] At 814, the O-RU may extract I / Q data corresponding to the PRACH preamble in the frequency domain from the results of the FFT performed per FFT window for each symbol of the PRACH preamble (e.g., as at 714). For example, 814 may be performed by the I / Q data processing component 942.

[0098] At 816, the O-RU may estimate a delay associated with the PRACH preamble (e.g., as at 716). The delay associated with the PRACH preamble may be estimated by performing an IFFT on the extracted I / Q data of the first FFT window to check for time-domain noise samples or by correlating with a reference PRACH preamble CP. For example, 816 may be performed by delay estimation component 944.

[0099] At 818, the O-RU may shift the first FFT window corresponding to the first symbol of the PRACH preamble in the time domain by the estimated delay (e.g., as at 718). The shifted first FFT window may span two symbols. For example, 818 may be performed by PRACH processing component 940.

[0100] At 820, the O-RU may perform an FFT for the shifted first FFT window (eg, as at 720). For example, 820 may be performed by PRACH processing component 940.

[0101] At 822, the O-RU may adjust the phase shift of the extracted I / Q data to account for the shift of each FFT window in the time domain compared to the FFT window of the PRACH preamble with the PRACH CP filtered out (e.g., as at 722) to generate I / Q data for the PRACH preamble. For example, 822 may be performed by I / Q data processing component 942.

[0102] At 824, the O-RU may send the I / Q data of the PRACH preamble to the O-DU (e.g., as at 724). For example, 824 may be performed by I / Q data processing component 942.

[0103] Figure 9FIG900 is a diagram illustrating an example of a hardware implementation for device 902. Device 902 is a base station and includes a baseband unit 904. Baseband unit 904 can communicate with UE 104 via a cellular RF transceiver. Baseband unit 904 may include computer-readable media / memory. Baseband unit 904 is responsible for general processing, including the execution of software stored on the computer-readable media / memory. This software, when executed by baseband unit 904, enables baseband unit 904 to perform the various functions described above. The computer-readable media / memory may also be used to store data manipulated by baseband unit 904 when executing the software. Baseband unit 904 further includes a receiving component 930, a communication manager 932, and a transmitting component 934. Communication manager 932 includes one or more of the illustrated components. Components within communication manager 932 may be stored in computer-readable media / memory and / or configured as hardware within baseband unit 904. The baseband unit 904 may be a component of the BS 310 and may include the memory 376 and / or at least one of the TX processor 316 , the RX processor 370 , and the controller / processor 375 .

[0104] The communication manager 932 includes a PRACH processing component 940 configured to: receive a PRACH preamble and a PUSCH within a plurality of symbols of a slot, the PRACH and the PUSCH having different parameter designs; filter the PUSCH CP for each symbol of the PRACH preamble by an FFT window extending from the end of the PUSCH CP within the symbol to the end of the symbol; shift a first FFT window corresponding to a first symbol of the PRACH by the PRACH CP in the time domain; perform an FFT on each FFT window of each symbol of the PRACH preamble; shift the first FFT window corresponding to the first symbol of the PRACH preamble by an estimated delay in the time domain; and perform an FFT on the shifted first FFT window, e.g., as described in conjunction with 806, 808, 810, 812, 818, and 820. The communication manager 932 further includes an I / Q data processing component 942 configured to: extract I / Q data corresponding to the PRACH preamble in the frequency domain from the results of the FFT performed per FFT window for each symbol of the PRACH preamble; adjust a phase shift of the extracted I / Q data to generate I / Q data for the PRACH preamble, the phase shift accounting for a shift in the time domain of each FFT window compared to the FFT window for the PRACH preamble with the PRACH CP filtered out; and send the I / Q data for the PRACH preamble to the O-DU, e.g., as described in connection with 814, 822, and 824. The communication manager 932 further includes a delay estimation component 944 configured to estimate a delay associated with the PRACH preamble, e.g., as described in connection with 816.

[0105] The apparatus may include executing Figure 7 and Figure 8 The additional components of each box of the algorithm in the preceding flowchart. Therefore, Figure 7 and Figure 8 Each block in the aforementioned flow chart can be performed by a component, and the device may include one or more of these components. These components can be one or more hardware components specifically configured to perform the process / algorithm, implemented by a processor configured to perform the process / algorithm, stored in a computer-readable medium for implementation by a processor, or some combination thereof.

[0106] In one configuration, the apparatus 902 (and in particular the baseband unit 904) includes: means for receiving a PRACH preamble and a PUSCH within a plurality of symbols of a slot, the PRACH and the PUSCH having different parameter designs, the PRACH preamble including a PRACH CP in a first symbol of the slot, and the PUSCH including a PUSCH CP in each symbol of the slot; means for filtering the PUSCH CP for each symbol of the PRACH preamble via an FFT window, the FFT window extending from an end of the PUSCH CP within the symbol to an end of the symbol; and means for performing an FFT in each FFT window for each symbol of the PRACH preamble. The apparatus 902 includes means for adjusting a phase shift of the extracted I / Q data to generate I / Q data for a PRACH preamble, the phase shift accounting for a shift in the time domain of each FFT window compared to the FFT window of the PRACH preamble with the PRACH CP filtered out, and means for transmitting the I / Q data for the PRACH preamble to the O-DU. The apparatus 902 also includes means for extracting I / Q data corresponding to the PRACH preamble in the frequency domain from the results of an FFT performed per FFT window for each symbol of the PRACH preamble; means for estimating a delay associated with the PRACH preamble; means for shifting a first FFT window corresponding to a first symbol of the PRACH preamble in the time domain by the estimated delay; and means for performing an FFT on the shifted first FFT window. The aforementioned means may be one or more of the aforementioned components of the apparatus 902 configured to perform the functions recited by the aforementioned means. As described above, the device 902 may include the TX processor 316, the RX processor 370, and the controller / processor 375. As such, in one configuration, the aforementioned means may be the TX processor 316, the RX processor 370, and the controller / processor 375 configured to perform the functions recited by the aforementioned means.

[0107] Reference again Figure 4 、 5, 6, 7, 8 and 9, the O-RU may: receive a PRACH preamble and a PUSCH within multiple symbols of a slot, the PRACH and the PUSCH having different parameter designs. The O-RU may: filter the PUSCH CP for each symbol of the PRACH preamble using an FFT window extending from the end of the PUSCH CP within the symbol to the end of the symbol; and perform an FFT on each FFT window of each symbol of the PRACH preamble. The O-RU may: extract I / Q data corresponding to the PRACH preamble in the frequency domain; adjust the phase shift of the extracted I / Q data to generate I / Q data of the PRACH preamble, the phase shift accounting for the shift of each FFT window in the time domain compared to the FFT window of the PRACH preamble with the PRACH CP filtered out; and send the I / Q data of the PRACH preamble to the O-DU. The O-RU may estimate the delay associated with the PRACH preamble; shift a first FFT window corresponding to a first symbol of the PRACH preamble in the time domain by the estimated delay; and perform an FFT on the shifted first FFT window. The delay associated with the PRACH preamble is estimated by performing an inverse FFT (IFFT) on the extracted I / Q data of the first FFT window to check for time-domain noise samples or to correlate with a reference PRACH preamble CP. The shifted first FFT window spans two symbols. The O-RU may also shift the first FFT window corresponding to the first symbol of the PRACH in the time domain by the PRACH CP.

[0108] It should be understood that the specific order or hierarchy of the blocks in the disclosed process / flowcharts is an illustration of an example approach. It should be understood that the specific order or hierarchy of the blocks in these process / flowcharts can be rearranged based on design preferences. In addition, some blocks can be combined or omitted. The accompanying method claims present the elements of the various blocks in an example order and are not meant to be limited to the specific order or hierarchy presented.

[0109] The preceding description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the universal principles defined herein can be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but should be granted the full scope consistent with the claims in language, wherein the citation of the singular form of an element is not intended to represent "there is and only one", but "one or more", unless otherwise stated. Terms such as "if", "when..." and "at..." should be interpreted as meaning "under the condition", rather than implying a direct temporal relationship or reaction. That is, these phrases (e.g., "when...") do not imply an immediate action in response to the occurrence of an action or during the occurrence of an action, but only imply that an action will occur when the condition is met, without requiring a specific or immediate time constraint for the action to occur. The word "exemplary" is used herein to mean "used as an example, instance or illustration". Any aspect described herein as "exemplary" is not necessarily to be interpreted as being superior to or superior to other aspects. Unless otherwise stated, the term "some / certain" refers to one or more. Combinations such as "at least one of A, B, or C," "one or more of A, B, or C," "at least one of A, B, and C," "one or more of A, B, and C," and "A, B, C, or any combination thereof" include any combination of A, B, and / or C and may include multiple A's, multiple B's, or multiple C's. Specifically, combinations such as "at least one of A, B, or C," "one or more of A, B, or C," "at least one of A, B, and C," "one or more of A, B, and C," and "A, B, C, or any combination thereof" may be only A, only B, only C, A and B, A and C, B and C, or A, B, and C, where any such combination may include one or more members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are now or later known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. In addition, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The terms “module,” “mechanism,” “element,” “device,” etc. may not be substitutes for the term “means.” Thus, no claim element should be construed as means-plus-function unless the element is explicitly recited using the phrase “means for.”

[0110] The following examples are merely illustrative and may be combined with other embodiments or aspects of the teachings described herein without limitation.

[0111] Example 1 is a method for wireless communication at an O-RU, comprising: receiving a PRACH preamble and a PUSCH within multiple codewords of a time slot, the PRACH and the PUSCH having different parameter designs, the PRACH preamble including a PRACH CP in the first codeword of the time slot, and the PUSCH including a PUSCH CP in each codeword of the time slot; filtering the PUSCH CP for each codeword of the PRACH preamble through an FFT window for each codeword of the PRACH preamble, the FFT window extending from an end of the PUSCH CP in the codeword to an end of the codeword; and performing an FFT in each FFT window for each codeword of the PRACH preamble.

[0112] Example 2 is the method of Example 1, wherein the first FFT window of the first symbol includes a portion of the PRACH CP.

[0113] Example 3 is the method of any one of Examples 1 and 2, further comprising extracting I / Q data corresponding to the PRACH preamble in the frequency domain from a result of the FFT performed per FFT window for each symbol of the PRACH preamble.

[0114] Example 4 is the method of any one of Examples 1 to 3, further comprising: adjusting a phase shift of the extracted I / Q data to generate I / Q data of a PRACH preamble, the phase shift accounting for a shift in the time domain of each FFT window compared to an FFT window of the PRACH preamble from which the PRACH CP is filtered; and sending the I / Q data of the PRACH preamble to the O-DU.

[0115] Example 5 is the method of any one of Examples 1 and 2, further comprising: extracting I / Q data corresponding to the PRACH preamble in the frequency domain from a result of an FFT performed on each FFT window of each symbol of the PRACH preamble; estimating a delay associated with the PRACH preamble; shifting a first FFT window corresponding to a first symbol of the PRACH preamble by the estimated delay in the time domain; and performing an FFT on the shifted first FFT window.

[0116] Example 6 is the method of any one of Examples 1, 2, and 5, wherein the delay associated with the PRACH preamble is estimated by at least one of: performing IFFT on the extracted I / Q data of the first FFT window to check for a time domain noise text or correlating with a reference PRACH preamble CP.

[0117] Example 7 is the method of any of Examples 1, 2, 5, and 6, wherein the shifted first FFT window spans two symbols.

[0118] Example 8 is the method of any of Examples 1 and 2, further comprising: adjusting a phase shift of the extracted I / Q data to generate I / Q data of a PRACH preamble, the phase shift accounting for a shift in the time domain of each FFT window compared to an FFT window of the PRACH preamble from which the PRACH CP is filtered; and sending the I / Q data of the PRACH preamble to the O-DU.

[0119] Example 9 is the method of any one of Examples 1, 2, and 8, wherein filtering the PUSCH CP for each symbol of the PRACH preamble by the FFT window includes shifting a first FFT window corresponding to a first symbol of the PRACH by the PRACH CP in the time domain.

[0120] Example 10 is the method of any of Examples 1, 2, 8, and 9, wherein the first FFT window of the first symbol includes a portion of the PRACHCP.

[0121] Example 11 is the method of any one of Examples 1, 2, 8, 9, and 10, further comprising extracting I / Q data corresponding to the PRACH preamble in the frequency domain from a result of the FFT performed per FFT window for each symbol of the PRACH preamble.

[0122] Example 12 is the method of any one of Examples 1, 2, 8, 9, 10, and 11, further comprising: adjusting a phase shift of the extracted I / Q data, except for the first FFT window, to generate I / Q data of a PRACH preamble, the phase shift accounting for a shift in the time domain of each FFT window compared to an FFT window of the PRACH preamble from which the PRACH CP is filtered; and sending the I / Q data of the PRACH preamble to the O-DU.

[0123] Example 13 is a device comprising one or more processors and one or more memories in electronic communication with the one or more processors, the one or more memories storing instructions executable by the one or more processors to cause the device to implement a method as in any of Examples 1-12.

[0124] Example 14 is a system or apparatus comprising means for implementing the method as in any of Examples 1-12 or implementing the apparatus as in any of Examples 16-27.

[0125] Example 15 is a non-transitory computer-readable medium storing instructions executable by one or more processors to cause the one or more processors to implement the method as in any of Examples 1-12.

Claims

1. A method of wirelessly communicating at an Open Radio Access Network (O-RAN) radio unit (O-RU), comprising: receiving a physical random access channel (PRACH) preamble and a physical uplink shared channel (PUSCH) within a plurality of symbols of a time slot, the PRACH and the PUSCH having different parameter designs, the PRACH preamble including a PRACH cyclic prefix (CP) in a first symbol of the time slot, and the PUSCH including a PUSCH CP in each symbol of the time slot; filtering the PUSCH CP for each symbol of the PRACH preamble by a Fast Fourier Transform (FFT) window, the FFT window extending from an end of the PUSCH CP within a symbol to an end of the symbol; Performing an FFT in each FFT window of each symbol of the PRACH preamble; extracting in-phase and quadrature (I / Q) data corresponding to the PRACH preamble in the frequency domain from a result of FFT performed per FFT window on each symbol of the PRACH preamble; estimating a delay associated with the PRACH preamble; shifting a first FFT window corresponding to a first symbol of the PRACH preamble by an estimated delay in the time domain; as well as An FFT is performed on the shifted first FFT window.

2. The method of claim 1, wherein a first FFT window of the first symbol includes a portion of the PRACH CP.

3. The method of claim 1 , wherein the delay associated with the PRACH preamble is estimated by at least one of: Checking the time domain noise samples by performing an inverse FFT (IFFT) on the extracted I / Q data of the first FFT window, or Correlate with the reference PRACH preamble CP. The method of claim 1 , wherein the shifted first FFT window spans two symbols.

5. The method of claim 1, further comprising: adjusting a phase shift of the extracted I / Q data to generate I / Q data of the PRACH preamble, the phase shift accounting for a shift in the time domain of each FFT window compared to an FFT window of the PRACH preamble from which the PRACH CP is filtered; and The I / Q data of the PRACH preamble is sent to an O-RAN distribution unit (O-DU).

6. An apparatus for wireless communication at an Open Radio Access Network (O-RAN) Radio Unit (O-RU), comprising: means for receiving a physical random access channel (PRACH) preamble and a physical uplink shared channel (PUSCH) within a plurality of symbols of a slot, the PRACH and the PUSCH having different parameter designs, the PRACH preamble including a PRACH cyclic prefix (CP) in a first symbol of the slot, and the PUSCH including a PUSCH CP in each symbol of the slot; means for filtering the PUSCH CP for each symbol of the PRACH preamble by a Fast Fourier Transform (FFT) window, the FFT window extending from an end of the PUSCH CP within a symbol to an end of the symbol; means for performing an FFT on each FFT window of each symbol of the PRACH preamble; means for extracting in-phase and quadrature (I / Q) data corresponding to the PRACH preamble in the frequency domain from a result of an FFT performed per FFT window on each symbol of the PRACH preamble; means for estimating a delay associated with said PRACH preamble; means for shifting in the time domain a first FFT window corresponding to a first symbol of the PRACH preamble by an estimated delay; as well as Means for performing an FFT on the shifted first FFT window.

7. The apparatus of claim 6, wherein a first FFT window of the first symbol includes a portion of the PRACH CP.

8. The apparatus of claim 6 , wherein the means for estimating the delay associated with the PRACH is configured to: Checking the time domain noise samples by performing an inverse FFT (IFFT) on the extracted I / Q data of the first FFT window, or Correlate with the reference PRACH preamble CP.

9. The apparatus of claim 6, wherein the shifted first FFT window spans two symbols.

10. The apparatus of claim 6, further comprising: means for adjusting a phase shift of the extracted I / Q data to generate I / Q data of the PRACH preamble, the phase shift accounting for a shift in the time domain of each FFT window compared to an FFT window of the PRACH preamble from which the PRACH CP is filtered; as well as means for sending the I / Q data of the PRACH preamble to an O-RAN distribution unit (O-DU).

11. An apparatus for wireless communication at an Open Radio Access Network (O-RAN) radio unit (O-RU), comprising: Memory; as well as at least one processor coupled to the memory and configured to: receiving a physical random access channel (PRACH) preamble and a physical uplink shared channel (PUSCH) within a plurality of symbols of a time slot, the PRACH and the PUSCH having different parameter designs, the PRACH preamble including a PRACH cyclic prefix (CP) in a first symbol of the time slot, and the PUSCH including a PUSCH CP in each symbol of the time slot; filtering the PUSCH CP for each symbol of the PRACH preamble by a Fast Fourier Transform (FFT) window, the FFT window extending from an end of the PUSCH CP within a symbol to an end of the symbol; Performing an FFT in each FFT window of each symbol of the PRACH preamble; extracting in-phase and quadrature (I / Q) data corresponding to the PRACH preamble in the frequency domain from a result of FFT performed per FFT window on each symbol of the PRACH preamble; estimating a delay associated with the PRACH preamble; shifting a first FFT window corresponding to a first symbol of the PRACH preamble by an estimated delay in the time domain; as well as An FFT is performed on the shifted first FFT window.

12. The apparatus of claim 11, wherein a first FFT window of the first symbol includes a portion of the PRACH CP.

13. The apparatus of claim 11 , wherein the delay associated with the PRACH preamble is estimated by the at least one processor configured to perform at least one of: Checking the time domain noise samples by performing an inverse FFT (IFFT) on the extracted I / Q data of the first FFT window, or Correlate with the reference PRACH preamble CP.

14. The apparatus of claim 11, wherein the shifted first FFT window spans two symbols.

15. The apparatus of claim 11 , wherein the at least one processor is further configured to: adjusting a phase shift of the extracted I / Q data to generate I / Q data of the PRACH preamble, the phase shift accounting for a shift in the time domain of each FFT window compared to an FFT window of the PRACH preamble from which the PRACH CP is filtered; and The I / Q data of the PRACH preamble is sent to an O-RAN distribution unit (O-DU).

16. A computer-readable medium storing computer-executable code for an Open Radio Access Network (O-RAN) Radio Unit (O-RU), the code, when executed by a processor, causing the processor to: receiving a physical random access channel (PRACH) preamble and a physical uplink shared channel (PUSCH) within a plurality of symbols of a time slot, the PRACH and the PUSCH having different parameter designs, the PRACH preamble including a PRACH cyclic prefix (CP) in a first symbol of the time slot, and the PUSCH including a PUSCH CP in each symbol of the time slot; filtering the PUSCH CP for each symbol of the PRACH preamble by a Fast Fourier Transform (FFT) window, the FFT window extending from an end of the PUSCH CP within a symbol to an end of the symbol; Performing an FFT in each FFT window of each symbol of the PRACH preamble; extracting in-phase and quadrature (I / Q) data corresponding to the PRACH preamble in the frequency domain from a result of FFT performed per FFT window on each symbol of the PRACH preamble; estimating a delay associated with the PRACH preamble; shifting a first FFT window corresponding to a first symbol of the PRACH preamble by an estimated delay in the time domain; and An FFT is performed on the shifted first FFT window.

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