Embodiments pertain to wireless communications including wireless local area networks (WLANS). Some embodiments relate to ranging for next generation vehicle-to-everything (NGV) communication. Some embodiments relate to ranging in accordance with an IEEE 802.11bd standard or draft standard.
One issue with next generation vehicle-to-everything (NGV) communication is that ranging, the ranging process and the associated control signalling for operating in accordance with IEEE 802.11bd are currently undefined. Thus there are needs for procedures for ranging for NGV communication.
The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims.
Some embodiments are directed to a next generation vehicle-to-everything (NGV) station (STA). In these embodiments, when operating as an initiating station (ISTA) for performing non-trigger-based NGV ranging, the NGV STA may encode an NGV ranging null-data packet (NDP) announcement (NGV NDPA) frame for transmission to a responding station (RSTA) to initiate the non-trigger-based NGV ranging. The NGV STA may also encode an initiator-to-responder (I2R) NGV ranging null-data packet (NDP) (I2R NGV ranging NDP) for transmission following the NGV NDPA frame. In some embodiments, the I2R NGV ranging NDP may be encoded in accordance with a NGV Ranging NDP format. In these embodiments, the NGV ranging NDP may be encoded to include an NGV signal field (NGV-SIG), a repeated NGV-SIG (RNGV-SIG), an NGV Short Training field (NGV-STF) and an NGV long training field (NGV-LTF). In these embodiments, the NGV-LTF may include one or two sets of LTF symbols depending on a number of LTF symbol repetitions (LTF_REP). In these embodiments, each set of LTF symbols may have one or two LTF symbols depending on a number of spatial streams (NUM_SS). In these embodiments, the NGV-LTF may be encoded without a packet extension (PE).
In some embodiments, the non-trigger based NGV ranging may be performed in accordance with an IEEE 802.11bd standard or draft standard, although the scope of the embodiments is not limited in this respect.
In some embodiments, the NGV-LTF may be encoded in symbol format NGV-LTF-2x. In these embodiments, symbols of the NGV-LTF may have a duration of 8 microseconds (μs) with a cyclic prefix (CP) of 1.6 μs. In some embodiments, the NGV-SIG, the RNGV-SIG, the NGV-STF and the NGV-LTF, each may have a symbol duration of 8 μs.
In some embodiments, for two spatial streams (NUM_SS=2) with LTF symbol repetition (LTF_REP=1), a first LTF symbol for spatial streams 1 and 2 may be transmitted by a first antenna (antenna 1) and a second antenna (antenna 2) with the same phase, followed by a second LTF symbol for spatial streams 1 and 2 transmitted by the first antenna and the second antenna with opposite phases, respectively, followed by repetition of the first and the second LTF symbols by antenna 1 and antenna 2 as the third and fourth LTF symbols. In these embodiments, NGV-LTF-2x symbol format may comprise an NGV-LTF-2x symbol A1 and an NGV-LTF-2x symbol A2 for one spatial stream, and an NGV-LTF-2x symbol A1 and an NGV-LTF-2x symbol A2 followed by NGV-LTF-2x symbol B1 and an NGV-LTF-2x symbol B2 for two spatial streams.
An example of NGV-LTF with N_SS=2 and LTF_REP=1, the repetition may be done after the LTF symbols of all spatial streams are sent. For example, for two spatial streams with LTF symbol repetition, a first LTF symbol for the two spatial streams may be transmitted by multiple antennas with a set of phases, followed by a second LTF symbol for the two spatial streams transmitted by the same multiple antennas with a different set of phases, respectively, followed by repetition of the first and the second LTF symbols by the same multiple antennas as the third and fourth LTF symbols.
In some embodiments, the NGV STA may set a predetermined bit (i.e., B12) to a predetermine value (i.e., 1) in the NGV-SIG to indicate that that the NGV Ranging NDP is an NGV Ranging NDP with NGV-LTF repetition.
In some embodiments, for transmission of an NGV PPDU with a data field and for transmission of an NGV Ranging NDP without NGV-LTF repetition, the NGV STA may set the predetermined bit to another predetermined value (i.e., 0) of the NGV-SIG. In these embodiments, bit 12 (B12) of the NGV-SIG field may be used to indicate NGV-LTF repetition. In these embodiments, B12 may be set to 0 for an NGV PPDU with a Data field and an NGV ranging NDP without NGV-LTF repetition. In these embodiments, B12 may be set to I for an NGV Ranging NDP with NGV-LTF repetition. In these embodiments, the NGV Ranging NDP format may comprise a NGV PPDU without a data field.
In some embodiments, in response to transmission of the I2R NGV ranging NDP, the NGV STA may decode a responder-to-initiator NGV-NDP (R2I NGV NDP) received from the RSTA following by an R2I link management report (R2I LMR) frame. The R2I LMR frame may report an arrival time of the I2R NGV NDP and a departure time of the R2I NGV NDP.
In some embodiments, the NGV STA may be configured for multiple frame transmission in an enhanced distributed coordination function (EDCA) TXOP. In these embodiments, during the EDCA TXOP for single user (SU) NGV ranging, the NGV STA may transmit the NGV Ranging NDP Announcement frame, may transmit the I2R NGV ranging NDP an SIFS after the NGV Ranging NDP Announcement frame, may receive the R2I NGV ranging NDP an SIFS after the I2R NGV ranging NDP, may receive the R2I LMR frame an SIFS after the R2I NGV ranging NDP, and may optionally transmit a I2R LMR frame an SIFS after receipt of the R2I LMR frame. An example of this is illustrated in
In some embodiments, the NGV STA may encode the NGV NDPA frame to include a STA information field (see
In some of these embodiments, the N_STS subfield may be set according to the number of spatial streams and Rep subfield may be set according to the number of LTF repetitions, although the scope of the embodiments is not limited in this respect.
Some embodiments are directed to non-transitory computer-readable storage medium that stores instructions for execution by processing circuitry of a next generation vehicle-to-everything (NGV) station (STA). In these embodiments, when operating as an initiating station (ISTA) for performing non-trigger-based NGV ranging, the processing circuitry may encode an NGV ranging null-data packet (NDP) announcement (NGV NDPA) frame for transmission to a responding station (RSTA) to initiate the non-trigger-based NGV ranging. The processing circuitry may also encode an initiator-to-responder (I2R) NGV ranging null-data packet (NDP) (I2R NGV ranging NDP) for transmission following the NGV NDPA frame. The I2R NGV ranging NDP may encoded in accordance with a NGV Ranging NDP format as discussed herein.
Some embodiments are directed to next generation vehicle-to-everything (NGV) station (STA) that when operating as a responding station (RSTA) for performing non-trigger-based NGV ranging, the NGV STA may be configured to decode an NGV ranging null-data packet (NDP) announcement (NGV NDPA) frame received from an initiating station (ISTA). The NGV NDPA may initiate non-trigger-based NGV ranging. The NGV STA may also decode an initiator-to-responder (I2R) NGV ranging null-data packet (NDP) (I2R NGV ranging NDP) received from the ISTA following the NGV NDPA frame. The I2R NGV ranging NDP may be encoded in accordance with a NGV Ranging NDP format as discussed herein.
FEM circuitry 104 may include a WLAN or Wi-Fi FEM circuitry 104A and a Bluetooth (BT) FEM circuitry 104B. The WLAN FEM circuitry 104A may include a receive signal path comprising circuitry configured to operate on WLAN RF signals received from one or more antennas 101, to amplify the received signals and to provide the amplified versions of the received signals to the WLAN radio IC circuitry 106A for further processing. The BT FEM circuitry 104B may include a receive signal path which may include circuitry configured to operate on BT RF signals received from one or more antennas 101, to amplify the received signals and to provide the amplified versions of the received signals to the BT radio IC circuitry 106B for further processing. FEM circuitry 104A may also include a transmit signal path which may include circuitry configured to amplify WLAN signals provided by the radio IC circuitry 106A for wireless transmission by one or more of the antennas 101. In addition, FEM circuitry 104B may also include a transmit signal path which may include circuitry configured to amplify BT signals provided by the radio IC circuitry 106B for wireless transmission by the one or more antennas. In the embodiment of
Radio IC circuitry 106 as shown may include WLAN radio IC circuitry 106A and BT radio IC circuitry 106B. The WLAN radio IC circuitry 106A may include a receive signal path which may include circuitry to down-convert WLAN RF signals received from the FEM circuitry 104A and provide baseband signals to WLAN baseband processing circuitry 108A. BT radio IC circuitry 106B may in turn include a receive signal path which may include circuitry to down-convert BT RF signals received from the FEM circuitry 104B and provide baseband signals to BT baseband processing circuitry 108B. WLAN radio IC circuitry 106A may also include a transmit signal path which may include circuitry to up-convert WLAN baseband signals provided by the WLAN baseband processing circuitry 108A and provide WLAN RF output signals to the FEM circuitry 104A for subsequent wireless transmission by the one or more antennas 101. BT radio IC circuitry 106B may also include a transmit signal path which may include circuitry to up-convert BT baseband signals provided by the BT baseband processing circuitry 108B and provide BT RF output signals to the FEM circuitry 104B for subsequent wireless transmission by the one or more antennas 101. In the embodiment of
Baseband processing circuitry 108 may include a WLAN baseband processing circuitry 108A and a BT baseband processing circuitry 108B. The WLAN baseband processing circuitry 108A may include a memory, such as, for example, a set of RAM arrays in a Fast Fourier Transform or Inverse Fast Fourier Transform block (not shown) of the WLAN baseband processing circuitry 108A. Each of the WLAN baseband circuitry 108A and the BT baseband circuitry 108B may further include one or more processors and control logic to process the signals received from the corresponding WLAN or BT receive signal path of the radio IC circuitry 106, and to also generate corresponding WLAN or BT baseband signals for the transmit signal path of the radio IC circuitry 106. Each of the baseband processing circuitries 108A and 108B may further include physical layer (PHY) and medium access control layer (MAC) circuitry and may further interface with application processor 111 for generation and processing of the baseband signals and for controlling operations of the radio IC circuitry 106.
Referring still to
In some embodiments, the front-end module circuitry 104, the radio IC circuitry 106, and baseband processing circuitry 108 may be provided on a single radio card, such as wireless radio card 102. In some other embodiments, the one or more antennas 101, the FEM circuitry 104 and the radio IC circuitry 106 may be provided on a single radio card. In some other embodiments, the radio IC circuitry 106 and the baseband processing circuitry 108 may be provided on a single chip or integrated circuit (IC), such as IC 112.
In some embodiments, the wireless radio card 102 may include a WLAN radio card and may be configured for Wi-Fi communications, although the scope of the embodiments is not limited in this respect. In some of these embodiments, the radio architecture 100 may be configured to receive and transmit orthogonal frequency division multiplexed (OFDM) or orthogonal frequency division multiple access (OFDMA) communication signals over a multicarrier communication channel. The OFDM or OFDMA signals may comprise a plurality of orthogonal subcarriers.
In some of these multicarrier embodiments, radio architecture 100 may be part of a Wi-Fi communication station (STA) such as a wireless access point (AP), a base station or a mobile device including a Wi-Fi device. In some of these embodiments, radio architecture 100 may be configured to transmit and receive signals in accordance with specific communication standards and/or protocols, such as any of the Institute of Electrical and Electronics Engineers (IEEE) standards including, IEEE 802.11n-2009, IEEE 802.11-2012, IEEE 802.11-2016, IEEE 802.11ac, and/or IEEE 802.11ax standards and/or proposed specifications for WLANs, although the scope of embodiments is not limited in this respect. Radio architecture 100 may also be suitable to transmit and/or receive communications in accordance with other techniques and standards.
In some embodiments, the radio architecture 100 may be configured for high-efficiency (HE) Wi-Fi (HEW) communications in accordance with the IEEE 802.11ax standard. In some embodiments, the radio architecture 100 may be configured for Extremely High Throughput (EHT) communications in accordance with the IEEE 802.11be standard. In these embodiments, the radio architecture 100 may be configured to communicate in accordance with an OFDMA technique, although the scope of the embodiments is not limited in this respect. In some embodiments, the radio architecture 100 may be configured for next generation vehicle-to-everything (NGV) communications in accordance with the IEEE 802.11bd standard and one or more stations including the AP 502 may be next generation vehicle-to-everything (NGV) stations (STAs).
In some other embodiments, the radio architecture 100 may be configured to transmit and receive signals transmitted using one or more other modulation techniques such as spread spectrum modulation (e.g., direct sequence code division multiple access (DS-CDMA) and/or frequency hopping code division multiple access (FH-CDMA)), time-division multiplexing (TDM) modulation, and/or frequency-division multiplexing (FDM) modulation, although the scope of the embodiments is not limited in this respect.
In some embodiments, as further shown in
In some embodiments, the radio-architecture 100 may include other radio cards, such as a cellular radio card configured for cellular (e.g., 3GPP such as LTE, LTE-Advanced or 5G communications).
In some IEEE 802.11 embodiments, the radio architecture 100 may be configured for communication over various channel bandwidths including bandwidths having center frequencies of about 900 MHz, 2.4 GHz, 5 GHz, and bandwidths of about 1 MHz, 2 MHz, 2.5 MHz, 4 MHz, 5 MHz, 8 MHz, 10 MHz, 16 MHz, 20 MHz, 40 MHz, 80 MHz (with contiguous bandwidths) or 80+80 MHz (160 MHz) (with non-contiguous bandwidths). In some embodiments, a 320 MHz channel bandwidth may be used. The scope of the embodiments is not limited with respect to the above center frequencies, however.
In some embodiments, the FEM circuitry 200 may include a TX/RX switch 202 to switch between transmit mode and receive mode operation. The FEM circuitry 200 may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry 200 may include a low-noise amplifier (LNA) 206 to amplify received RF signals 203 and provide the amplified received RF signals 207 as an output (e.g., to the radio IC circuitry 106 (
In some dual-mode embodiments for Wi-Fi communication, the FEM circuitry 200 may be configured to operate in either the 2.4 GHz frequency spectrum or the 5 GHz frequency spectrum. In these embodiments, the receive signal path of the FEM circuitry 200 may include a receive signal path duplexer 204 to separate the signals from each spectrum as well as provide a separate LNA 206 for each spectrum as shown. In these embodiments, the transmit signal path of the FEM circuitry 200 may also include a power amplifier 210 and a filter 212, such as a BPF, a LPF or another type of filter for each frequency spectrum and a transmit signal path duplexer 214 to provide the signals of one of the different spectrums onto a single transmit path for subsequent transmission by the one or more of the antennas 101 (
In some embodiments, the radio IC circuitry 300 may include a receive signal path and a transmit signal path. The receive signal path of the radio IC circuitry 300 may include at least mixer circuitry 302, such as, for example, down-conversion mixer circuitry, amplifier circuitry 306 and filter circuitry 308. The transmit signal path of the radio IC circuitry 300 may include at least filter circuitry 312 and mixer circuitry 314, such as, for example, up-conversion mixer circuitry. Radio IC circuitry 300 may also include synthesizer circuitry 304 for synthesizing a frequency 305 for use by the mixer circuitry 302 and the mixer circuitry 314. The mixer circuitry 302 and/or 314 may each, according to some embodiments, be configured to provide direct conversion functionality. The latter type of circuitry presents a much simpler architecture as compared with standard super-heterodyne mixer circuitries, and any flicker noise brought about by the same may be alleviated for example through the use of OFDM modulation.
In some embodiments, mixer circuitry 302 may be configured to down-convert RF signals 207 received from the FEM circuitry 104 (
In some embodiments, the mixer circuitry 314 may be configured to up-convert input baseband signals 311 based on the synthesized frequency 305 provided by the synthesizer circuitry 304 to generate RF output signals 209 for the FEM circuitry 104. The baseband signals 311 may be provided by the baseband processing circuitry 108 and may be filtered by filter circuitry 312. The filter circuitry 312 may include a LPF or a BPF, although the scope of the embodiments is not limited in this respect.
In some embodiments, the mixer circuitry 302 and the mixer circuitry 314 may each include two or more mixers and may be arranged for quadrature down-conversion and/or up-conversion respectively with the help of synthesizer 304. In some embodiments, the mixer circuitry 302 and the mixer circuitry 314 may each include two or more mixers each configured for image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuitry 302 and the mixer circuitry 314 may be arranged for direct down-conversion and/or direct up-conversion, respectively. In some embodiments, the mixer circuitry 302 and the mixer circuitry 314 may be configured for super-heterodyne operation, although this is not a requirement.
Mixer circuitry 302 may comprise, according to one embodiment: quadrature passive mixers (e.g., for the in-phase (I) and quadrature phase (Q) paths). In such an embodiment, RF input signal 207 from
Quadrature passive mixers may be driven by zero and ninety-degree time-varying LO switching signals provided by a quadrature circuitry which may be configured to receive a LO frequency (fLO) from a local oscillator or a synthesizer, such as LO frequency 305 of synthesizer 304 (
In some embodiments, the LO signals may differ in duty cycle (the percentage of one period in which the LO signal is high) and/or offset (the difference between start points of the period). In some embodiments, the LO signals may have a 25% duty cycle and a 50% offset. In some embodiments, each branch of the mixer circuitry (e.g., the in-phase (I) and quadrature phase (Q) path) may operate at a 25% duty cycle, which may result in a significant reduction is power consumption.
The RF input signal 207 (
In some embodiments, the output baseband signals 307 and the input baseband signals 311 may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternate embodiments, the output baseband signals 307 and the input baseband signals 311 may be digital baseband signals. In these alternate embodiments, the radio IC circuitry may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry.
In some dual-mode embodiments, a separate radio IC circuitry may be provided for processing signals for each spectrum, or for other spectrums not mentioned here, although the scope of the embodiments is not limited in this respect.
In some embodiments, the synthesizer circuitry 304 may be a fractional-N synthesizer or a fractional N/N+1 synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, synthesizer circuitry 304 may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider. According to some embodiments, the synthesizer circuitry 304 may include digital synthesizer circuitry. An advantage of using a digital synthesizer circuitry is that, although it may still include some analog components, its footprint may be scaled down much more than the footprint of an analog synthesizer circuitry. In some embodiments, frequency input into synthesizer circuitry 304 may be provided by a voltage controlled oscillator (VCO), although that is not a requirement. A divider control input may further be provided by either the baseband processing circuitry 108 (
In some embodiments, synthesizer circuitry 304 may be configured to generate a carrier frequency as the output frequency 305, while in other embodiments, the output frequency 305 may be a fraction of the carrier frequency (e.g., one-half the carrier frequency, one-third the carrier frequency). In some embodiments, the output frequency 305 may be a LO frequency (fLO).
In some embodiments (e.g., when analog baseband signals are exchanged between the baseband processing circuitry 400 and the radio IC circuitry 106), the baseband processing circuitry 400 may include ADC 410 to convert analog baseband signals received from the radio IC circuitry 106 to digital baseband signals for processing by the RX BBP 402. In these embodiments, the baseband processing circuitry 400 may also include DAC 412 to convert digital baseband signals from the TX BBP 404 to analog baseband signals.
In some embodiments that communicate OFDM signals or OFDMA signals, such as through baseband processor 108A, the transmit baseband processor 404 may be configured to generate OFDM or OFDMA signals as appropriate for transmission by performing an inverse fast Fourier transform (IFFT). The receive baseband processor 402 may be configured to process received OFDM signals or OFDMA signals by performing an FFT. In some embodiments, the receive baseband processor 402 may be configured to detect the presence of an OFDM signal or OFDMA signal by performing an autocorrelation, to detect a preamble, such as a short preamble, and by performing a cross-correlation, to detect a long preamble. The preambles may be part of a predetermined frame structure for Wi-Fi communication.
Referring back to
Although the radio-architecture 100 is illustrated as having several separate functional elements, one or more of the functional elements may be combined and may be implemented by combinations of software-configured elements, such as processing elements including digital signal processors (DSPs), and/or other hardware elements. For example, some elements may comprise one or more microprocessors, DSPs, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), radio-frequency integrated circuits (RFICs) and combinations of various hardware and logic circuitry for performing at least the functions described herein. In some embodiments, the functional elements may refer to one or more processes operating on one or more processing elements.
The HE AP 502 may be an AP using the IEEE 802.11 to transmit and receive. The HE AP 502 may be a base station. The HE AP 502 may use other communications protocols as well as the IEEE 802.11 protocol. The IEEE 802.11 protocol may be IEEE 802.11ax. The IEEE 802.11 protocol may include using orthogonal frequency division multiple-access (OFDMA), time division multiple access (TDMA), and/or code division multiple access (CDMA). The IEEE 802.11 protocol may include a multiple access technique. For example, the IEEE 802.11 protocol may include space-division multiple access (SDMA) and/or multiple-user multiple-input multiple-output (MU-MIMO). There may be more than one HE AP 502 that is part of an extended service set (ESS). A controller (not illustrated) may store information that is common to the more than one HE APs 502.
The legacy devices 506 may operate in accordance with one or more of IEEE 802.11 a/b/g/n/ac/ad/af/ah/aj/ay, or another legacy wireless communication standard. The legacy devices 506 may be STAs or IEEE STAs. The HE STAs 504 may be wireless transmit and receive devices such as cellular telephone, portable electronic wireless communication devices, smart telephone, handheld wireless device, wireless glasses, wireless watch, wireless personal device, tablet, or another device that may be transmitting and receiving using the IEEE 802.11 protocol such as IEEE 802.1 lax or another wireless protocol. In some embodiments, the HE STAs 504 may be termed high efficiency (HE) stations.
The HE AP 502 may communicate with legacy devices 506 in accordance with legacy IEEE 802.11 communication techniques. In example embodiments, the HE AP 502 may also be configured to communicate with HE STAs 504 in accordance with legacy IEEE 802.11 communication techniques.
In some embodiments, a HE frame may be configurable to have the same bandwidth as a channel. The HE frame may be a physical Layer Convergence Procedure (PLCP) Protocol Data Unit (PPDU). In some embodiments, there may be different types of PPDUs that may have different fields and different physical layers and/or different media access control (MAC) layers.
The bandwidth of a channel may be 20 MHz, 40 MHz, or 80 MHz, 160 MHz, 320 MHz contiguous bandwidths or an 80+80 MHz (160 MHz) non-contiguous bandwidth. In some embodiments, the bandwidth of a channel may be 1 MHz, 1.25 MHz, 2.03 MHz, 2.5 MHz, 4.06 MHz, 5 MHz and 10 MHz, or a combination thereof or another bandwidth that is less or equal to the available bandwidth may also be used. In some embodiments the bandwidth of the channels may be based on a number of active data subcarriers. In some embodiments the bandwidth of the channels is based on 26, 52, 106, 242, 484, 996, or 2×996 active data subcarriers or tones that are spaced by 20 MHz. In some embodiments the bandwidth of the channels is 256 tones spaced by 20 MHz. In some embodiments the channels are multiple of 26 tones or a multiple of 20 MHz. In some embodiments a 20 MHz channel may comprise 242 active data subcarriers or tones, which may determine the size of a Fast Fourier Transform (FFT). An allocation of a bandwidth or a number of tones or sub-carriers may be termed a resource unit (RU) allocation in accordance with some embodiments.
In some embodiments, the 26-subcarrier RU and 52-subcarrier RU are used in the 20 MHz, 40 MHz, 80 MHz, 160 MHz and 80+80 MHz OFDMA HE PPDU formats. In some embodiments, the 106-subcarrier RU is used in the 20 MHz, 40 MHz, 80 MHz, 160 MHz and 80+80 MHz OFDMA and MU-MIMO HE PPDU formats. In some embodiments, the 242-subcarrier RU is used in the 40 MHz, 80 MHz, 160 MHz and 80+80 MHz OFDMA and MU-MIMO HE PPDU formats. In some embodiments, the 484-subcarrier RU is used in the 80 MHz, 160 MHz and 80+80 MHz OFDMA and MU-MIMO HE PPDU formats. In some embodiments, the 996-subcarrier RU is used in the 160 MHz and 80+80 MHz OFDMA and MU-MIMO HE PPDU formats.
A HE frame may be configured for transmitting a number of spatial streams, which may be in accordance with MU-MIMO and may be in accordance with OFDMA. In other embodiments, the HE AP 502, HE STA 504, and/or legacy device 506 may also implement different technologies such as code division multiple access (CDMA) 2000, CDMA 2000 1×, CDMA 2000 Evolution-Data Optimized (EV-DO), Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Long Term Evolution (LTE), Global System for Mobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), BlueTooth®, or other technologies.
Some embodiments relate to HE communications. In accordance with some IEEE 802.11 embodiments, e.g., IEEE 802.11ax embodiments, a HE AP 502 may operate as a master station which may be arranged to contend for a wireless medium (e.g., during a contention period) to receive exclusive control of the medium for an HE control period. In some embodiments, the HE control period may be termed a transmission opportunity (TXOP). The HE AP 502 may transmit a HE master-sync transmission, which may be a trigger frame or HE control and schedule transmission, at the beginning of the HE control period. The HE AP 502 may transmit a time duration of the TXOP and sub-channel information. During the HE control period, HE STAs 504 may communicate with the HE AP 502 in accordance with a non-contention based multiple access technique such as OFDMA or MU-MIMO. This is unlike conventional WLAN communications in which devices communicate in accordance with a contention-based communication technique, rather than a multiple access technique. During the HE control period, the HE AP 502 may communicate with HE stations 504 using one or more HE frames. During the HE control period, the HE STAs 504 may operate on a sub-channel smaller than the operating range of the HE AP 502. During the HE control period, legacy stations refrain from communicating. The legacy stations may need to receive the communication from the HE AP 502 to defer from communicating.
In accordance with some embodiments, during the TXOP the HE STAs 504 may contend for the wireless medium with the legacy devices 506 being excluded from contending for the wireless medium during the master-sync transmission. In some embodiments the trigger frame may indicate an uplink (UL) UL-MU-MIMO and/or UL OFDMA TXOP. In some embodiments, the trigger frame may include a DL UL-MU-MIMO and/or DL OFDMA with a schedule indicated in a preamble portion of trigger frame.
In some embodiments, the multiple-access technique used during the HE TXOP may be a scheduled OFDMA technique, although this is not a requirement. In some embodiments, the multiple access technique may be a time-division multiple access (TDMA) technique or a frequency division multiple access (FDMA) technique. In some embodiments, the multiple access technique may be a space-division multiple access (SDMA) technique. In some embodiments, the multiple access technique may be a Code division multiple access (CDMA).
The HE AP 502 may also communicate with legacy stations 506 and/or HE stations 504 in accordance with legacy IEEE 802.11 communication techniques. In some embodiments, the HE AP 502 may also be configurable to communicate with HE stations 504 outside the HE TXOP in accordance with legacy IEEE 802.11 communication techniques, although this is not a requirement.
In some embodiments the HE station 504 may be a “group owner” (GO) for peer-to-peer modes of operation. A wireless device may be a HE station 502 or a HE AP 502.
In some embodiments, the HE station 504 and/or HE AP 502 may be configured to operate in accordance with IEEE 802.11mc. In example embodiments, the radio architecture of
In example embodiments, the HE stations 504, HE AP 502, an apparatus of the HE stations 504, and/or an apparatus of the HE AP 502 may include one or more of the following: the radio architecture of
In example embodiments, the radio architecture of
In example embodiments, the HE station 504 and/or the HE AP 502 are configured to perform the methods and operations/functions described herein. In example embodiments, an apparatus of the HE station 504 and/or an apparatus of the HE AP 502 are configured to perform the methods and functions described herein. The term Wi-Fi may refer to one or more of the IEEE 802.11 communication standards. AP and STA may refer to HE access point 502 and/or HE station 504 as well as legacy devices 506.
In some embodiments, a HE AP STA may refer to a HE AP 502 and a HE STAs 504 that is operating a HE APs 502. In some embodiments, when an HE STA 504 is not operating as a HE AP, it may be referred to as a HE non-AP STA or HE non-AP. In some embodiments, HE STA 504 may be referred to as either a HE AP STA or a HE non-AP.
A new 802.11ngv air interface may be defined that is understood by legacy 80.211p (“11p) STAs (forward-compatible) but still provides improvements especially with regards to range: legacy compatible 802.11ngv (“11ngv) PPDU format (also referred to as next generation vehicle (NGV) Control PHY), and to define another 802.11ngv air interface that is not understood by legacy 11p STAs: legacy non-compatible 11ngv PPDU format (also referred to as NGV Enhanced PHY).
With the increased focus on enabling smart and increasingly autonomous vehicles, Vehicle-to-everything (V2X) has become one of the main target use cases to support over next-generation of wireless communication technologies, such as 5G. V2X communication is the passing of information from a vehicle to any entity that may affect the vehicle, and vice versa. It is a vehicular communication system that incorporates other more specific types of communication as V2I (Vehicle-to-Infrastructure), V2N (Vehicle-to-network), V2V (Vehicle-to-vehicle), V2P (Vehicle-to-Pedestrian), V2D (Vehicle-to-device) and V2G (Vehicle-to-grid).
Wireless ranging is a feature for 802.11bd, the next generation V2X (NGV) communications system. The ranging signal and control signaling are missing in the 802.11 specification draft. Existing solution was to use 802.11az bands to do the ranging for 802.11bd device.
Since the existing solution requires operations in another band, it is desirable to have a default solution that operates in the 802.11bd band.
Example embodiments of the present disclosure relate to systems, methods, and devices for NDP and NDPA Designs for 802.11bd.
In one embodiment, a ranging system may modify the NDP and NDPA frames of 11ax and 11az from designing the NDP and NDPA of 11bd. Although the physical layer of 11bd differs from 11ax, it is much simpler than those of 11ax and 11az. Therefore, simplifying the NDP and NDPA frames for 11ax and 11az for 11bd. The 11bd bands are reserved for vehicular communications. Having the ranging support in 11bd bands enhances the deployment of 11bd and is required by the 11bd task group.
No frame exchange sequence and no frame format are defined for 802.11bd ranging in the 802.11 spec draft. The frame exchange sequence for 802.11bd single user (SU) ranging can be the same as the 802.11az SU ranging as illustrated in
For simplicity, 11bd may only supports immediate feedback since the bandwidth is small, i.e., 10 or 20 MHz, and the SIFS is long, i.e., 32 microseconds. For immediate feedback, the LMR reports the measurement results of the NDP frames in the current measurement round (that is shown in
NGV-LTF SyMbol
In these embodiments, the total number of LTF symbols in an NGV-LTF symbol may be one, two, or four. For example, NGV-LTF symbol formats 702 and 704 have one LTF symbol, NGV-LTF symbol format 706 has two LTF symbols, and NGV-LTF symbol formats 708 and 710 have four LTF symbols. NGV-LTF symbol format 708 has four repeated LTF symbols proceeded by a GI. NGV-LTF symbol format 710 is a doubled version NGV-LTF symbol format 706.
For transmission of one spatial stream without NGV-LTF symbol repetition, the number of NGV-LTF symbols in the NGV-LTF is one. For transmission of one spatial stream with NGV-LTF repetition, the number of NGV-LTF symbols in the NGV-LTF is two. For transmission of two spatial streams without NGV-LTF repetition, the number of NGV-LTF symbols in the NGV-LTF is two. For transmission of two spatial streams with NGV-LTF repetition, the number of NGV-LTF symbols in the NGV-LTF is four.
For example, if NGV-LTF symbol format 704 is used for transmission of one spatial stream with NGV-LTF repetition, the number of NGV-LTF symbols in the NGV-LTF is two. Therefore the NGV Long Training Field (NGV LTF) would comprise two repetitions of NGV-LTF symbol format 704 which comprises two NGV-LTF symbols.
The existing NGV-LTF symbol (not field) structures are shown on the first 3 row of
For example, if NGV-LTF symbol format 704 is used for transmission of one spatial stream with NGV-LTF repetition, the number of NGV-LTF symbols in the NGV-LTF is two. Therefore the NGV Long Training Field (NGV LTF) would comprise two repetitions of NGV-LTF symbol format 704 which comprises two NGV-LTF symbols, as illustrated in
NDP Frame
Reusing the components of existing 11bd data frame, the structure of 11bd NDP frame is illustrated in
Option (b) in
Option (c) in
For combating the multipath delay, guard interval (GI) is applied to each sounding symbol of the NGV-LTF as illustrated in
Although it is proposed to have an NDPA before the sounding NDPs, a third-party device may not receive the NDPA due to the hidden problem or cochannel interference. In this case, the third-party device may not be able to interpret the sounding NDP frame correctly. For clarification, it is desirable that the NDP frame can indicate itself so that intended and unintended receivers can identify the NDP and know its format explicitly. To indicate the NDP frame, the NGV-SIG may be used, though using L-SIG is also doable with more changes. The existing fields in NGV-SIG are listed in Table 1. It should be noticed that there are unused or reserved entries in some fields and reserved field (or reserved bits). These reserved entries or bits can be used to indicate:
Some examples are listed as follows. In general, the NDP frame may be indicated in three ways:
Once the NDP frame is indicated, the other bits except B14-B23 can be redefined to indicate the NGV-LTF type and/or NGV-LTF field repetition and/or packet extension.
This example is the simplest with the fewest feature supports. The reserved entry in Midamble Periodicity may be used, i.e., the fourth entry with value 3, to indicate the NDP frame. For example, if B8-B9 is set to 3, NDP is indicated. The format of NGV-LTF in the ranging NDP can be only one type and can be mandated by the 802.11 spec, e.g., NGV-LTF-2x-Repeat (or NGV-LTF-2x). The indication of the NGV-LTF type is the same as the data PPDU. For example, MCS may be set to n=10 for DCM for using NGV-LTF-2x-Repeat, and MCS may be set to other values and LTF Format may be set to 0 for using NGV-LTF-2x. The NDPA frame of 11az can be reused for 11bd.
If support NGV-LTF field repetition is wanted, the repetition number may be indicated for example using the following bits: B11 LDPC Extra OFDM Symbol and/or B12-B13 Reserved bits and/or B3-B6 MCS. For example, B11 is set to 1 for NGV-LTF field repetition (e.g. two NGV-LTF fields) and B11 is set to 0 otherwise.
This example is similar to the previous except the multiple types of NGV-LTF can be used. The reserved entry in Midamble Periodicity may be used, i.e., the fourth entry with value 3, to indicate the NDP frame. For example, if B8-B9 is set 3, NDP is indicated. The format of NGV-LTF in the ranging NDP can be selected from the existing types, e.g., NGV-LTF-2x-Repeat and NGV-LTF-2x. The indication of the NGV-LTF type is the same as the 11bd data PPDU. For example, MCS may be set to n=10 for DCM for using NGV-LTF-2x-Repeat, and MCS may be set to other values and LTF Format may be set to 0 for using NGV-LTF-2x.
The reserved entries in MCS field may be used, i.e., 11-15, to indicate the NDP frame. For example, for B3-B6, set n=11 to indicate NDP. The format of NGV-LTF in the NDP can be indicated by B10, LTF Format field. Since NGV-LTF-1x may not be desirable for ranging due to the weak signal energy, NGV-LTF-2x-repeat may be used instead. For example, set B10 to 0 for NGV-LTF-2x; and set B10 to 1 for NGV-LTF-2x-Repeat; or vice versa. If NGV-LTF-2x-Repeat is not used for ranging, then B10 can be used as before, i.e., 0 for NGV-LTF-2x and 1 for NGV-LTF-1x. The irrelevant fields like B8-B9 and B11 can be reserved. The useful fields like B1-B2, B3, and B7 can be reused the same way as in the data PPDU.
The reserved entries in MCS field may be used to indicate the NDP frame. For example, for B3-B6, set n=11 to indicate NDP. The format of NGV-LTF in the NDP can be indicated by B10 and B11. For example, B10-B11 can be set as: 00 for NGV-LTF-2x, 10 for NGV-LTF-1x, 01 for NGV-2x-Repeat, (and may be 11 for two copies of NGV-LTF-2x-Repeat). The irrelevant fields like B8-B9 can be reserved. The useful fields like B1-B2, B3, and B7 can be reused the same way as in the data PPDU.
The reserved entries in MCS field may be used to indicate the NDP frame. For example, for B3-B6, set n=11 to indicate NDP. The format of NGV-LTF in the NDP can be indicated by B8-B9, Midamble Periodicity field. For example, set B8-B9 to 0 for NGV-LTF-1x; set B8-B9 to 1 for NGV-LTF-2x; set B8-B9 to 2 for NGV-LTF-2x-Repeat; set B8-B9 to 3 for two copies of NGV-LTF-2x-Repeat (or NGV-LTF-2x-Repeat with NGV-LTF field repetition). The irrelevant fields like B10 and B11 can be reserved. The useful fields like B1-B2, B3, and B7 can be reused the same way as in the data PPDU.
The reserved entries in MCS field may be used to indicate the NDP frame and the NGV-LTF format. For example, for B3-B6, set n=11 to indicate NDP with NGV-LTF-1x; set n=12 to indicate NDP with NGV-LTF-2x; and set n=13 to indicate NDP with NGV-LTF-2x-Repeat; set n=14 to indicate NDP with two copies of NGV-LTF-2x-Repeat (or NGV-LTF-2x-Repeat with NGV-LTF field repetition). If NGV-LTF-1x and NGV-LTF field repetition are not supported, two entries may be used, e.g., n=11 for NDP with NGV-LTF-2x and n=12 for NDP with NGV-LTF-2x-Repeat. The irrelevant fields like B10 and B11 can be reserved (or ignored). The useful fields like B1-B2, B3, and B7 can be reused the same way as in the data PPDU.
The examples above talk little about the indication for the repetition of NGV-LTF field as illustrated in
The reserved entries in MCS field may be used to indicate the NDP frame. For example, for B3-B6, set n=11 to indicate NDP. The format of NGV-LTF in the NDP can be indicated by B10, LTF Format field. B8-B9, Midamble Periodicity, can be used to indicate the number of repetitions, e.g., setting n to 0: 1 NGV-LTF; 1: 2 NGV-LTFs; 2: 3 NGV-LTFs; and 3: 4 NGV-LTFs.
In the examples above, it is desirable that the settings of NGV-LTF format (e.g., 1x, 2x, and 2x-Repeat) and NGV-LTF field repetition remain the same for both the I2R NDP and the R2I NDP. The 802.11bd spec can mandate this.
For calculating the length field of L-SIG and RL-SIG, the parameter of TXTIME in 802.11bd spec needs to take into account the removal of data symbols and the addition of extra NGV-LTF symbols and maybe the PE.
NDP Announcement Frame
The NDPA frame of 11az may be reused, whose STA Info field is shown in
Same as 1az, the 11bd ranging NDPA may be indicated by setting the HE subfield and the Ranging subfield in the Sounding Dialog Token field. The Ranging NDPA frame contains at least one STA Info field. If the Ranging NDPA frame contains only one STA Info field, then the RA address is set to the address of the RSTA (or ISTA) that is the intended recipient of the frame. If the Ranging NDPA frame contains more than one STA Info field, then the RA field is set to the broadcast address. For the non-trigger-based (non-TB) ranging of 11bd in
Since 11bd only supports single user (SU) mode, the LTF Offset field is not used or can be set to zero. The setting of the remaining fields in
For simplicity, 11bd may not support multiple NGV-LTF formats. In this case, the NDA frame of 11az can be reused. The AID11 and LTF Offset may be set to 0 for 11bd. R2I Rep and I2R Rep can be reused by 11bd if 11bd supports NGV-LTF field repetition as illustrated in
For other control frames and management frames such as initial Fine Timing Measurement Request frame (IFTMR), initial Fine Timing Measurement frame (IFTM), and location measurement report (LMR), 11bd may reuse the ones of 11az. It is understood that the above descriptions are for purposes of illustration and are not meant to be limiting.
In some embodiments, when used as part of non-TB Ranging measurement exchange for Non-TB Ranging measurement exchange, the I2R N_STS and I2R Rep subfields are used to indicate the configuration of HE-LTF and NGV-LTF of the following I2R NDPs. The R2I N_STS and R2I Rep subfields indicate the configuration of HE-LTF and NGV-LTF of the R2I NDP sent in response by the RSTA. When a Ranging NDP Announcement frame is configured for NGV ranging, the subfields of the STA Info field shall be set as follows:
In operation 1104, the NGV STA is configured to encode an initiator-to-responder (I2R) NGV ranging null-data packet (NDP) (I2R NGV ranging NDP) for transmission following the NGV NDPA frame. The I2R NGV ranging NDP may be encoded in accordance with a NGV Ranging NDP format, the NGV ranging NDP encoded to include an NGV signal field (NGV-SIG), a repeated NGV-SIG (RNGV-SIG), an NGV Short Training field (NGV-STF) and an NGV long training field (NGV-LTF).
In operation 1106, the NGV STA is encodes the NGV-LTF to include one or two sets of LTF symbols depending on a number of LTF symbol repetitions [(LTF_REP)] such that each set of LTF symbols have one or two LTF symbols depending on a number of spatial streams [NUM_SS]. In operation 1108, the NGV STA may transmit the encoded NGV NDPA followed by the NGV NDP.
The Abstract is provided to comply with 37 C.F.R. Section 1.72(b) requiring an abstract that will allow the reader to ascertain the nature and gist of the technical disclosure. It is submitted with the understanding that it will not be used to limit or interpret the scope or meaning of the claims. The following claims are hereby incorporated into the detailed description, with each claim standing on its own as a separate embodiment.
This application claims the benefit of priority to U.S. Provisional Patent Application Ser. No. 63/136,173, filed Jan. 11, 2021 [reference number AD4628-Z] which is incorporated herein by reference in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/US2021/061952 | 12/6/2021 | WO |
Number | Date | Country | |
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63136173 | Jan 2021 | US |