Abstract: A method of sub-channel independent network allocation vector (NAV) management by a wireless station (STA) in a wideband wireless communications system is proposed. In the wideband system having multiple sub-bands, each NAV for a corresponding sub-band is independently managed. The protection duration for each NAV is independent for each sub-band and the threshold or update rule for NAV modification is also independent for each sub-band. The threshold or update rule for NAV modification may also be different when the NAV is generated or propagated by an OBSS STA. Furthermore, early termination of NAV is allowed if the NAV is set by an OBSS STA only.

Abstract: A method of performing contention-based uplink OFDMA transmission is proposed in accordance with one novel aspect. A wireless communications station (an AP) reserves both dedicated resource and contention resource for uplink OFDMA operation for a list of communications devices (STAs). For contention-based random access, the AP does not need to collect traffic requests from the STAs. The AP only needs to make simple resource arrangement. The AP only needs to specify the allocated resource for random access and the uplink OFDMA operation duration and timing for each uplink OFDMA packet. Each STA having traffic request will contend the resource based on a random access probability scheme.

Abstract: Methods and apparatus are provided for clear channel assessment in the Wifi network. In one novel aspect, different clear channel assessment (CCA) threshold value is set for intra-BSS and inter-BSS frames during the counting down process. A CCA procedure senses the radio channel and determines if the radio channel is busy or idle during the backoff period by comparing the signal level value of detected fames with the CCA threshold value. The counting down will be suspended if the radio channel determined to be busy. If the detected frame is inter-BSS frame, the CCA threshold value is raised. If the signal level of the detected frames is lower than the inter-BSS CCA threshold for inter-BSS fames, the radio channel is considered idle. The counting down process is resumed.

Abstract: Methods and apparatus are provided for burst OFDMA support MU-MIMO in the WLAN network. In one novel aspect, pluralities of user channels are configured for a downlink wideband channel, wherein each user channel is associated with a user group selecting from a SU-SISO, or a SU-MIMO or a MU-MIMO. In one embodiment, the SIG1 and SIG2 signaling fields are independent for each user channel. In another embodiment, the SIG1 fields are duplicates for all user channels carrying common information. The SIG2 fields for each user group are different from each other carrying user group specific information. In another novel aspect, an uplink OFDMA frames contains ACK packets from multiple STAs concurrently using an uplink wideband channel. In one embodiment, one ACK packet is sent for a MU-MIMO user group. In another embodiment, the uplink ACK packet assignment is based on indications in the downlink PHY SIG field.

Abstract: Methods are provided for concurrent communications among multiple wireless communications devices. In one novel aspect, the wireless station transmits a wideband signal to a plurality of wireless communications devices using downlink MIMO and/or OFDMA. The wireless station receives a plurality of responding frames from the plurality of wireless communications devices concurrently using OFDMA. In one embodiment, the wireless station transmits a MU indication bit and MU bandwidth assignment information in the downlink MIMO and/or OFDMA frames. In another novel aspect, the uplink responding frames from multiple wireless communications devices are sent on a corresponding narrow concurrently over more than one transmission instance. AP polling or SIFS only is used between two transmission instances. When the concurrent responding frames occupies less than a bandwidth of an available uplink OFDMA bandwidth, the unoccupied bandwidth is either left empty or occupied by one or more duplicated responding frames.

Abstract: A method of a ranging and positioning with sensor STA/neighbor AP is proposed. An initiating wireless device establishes an FTM procedure with a responding wireless device in an indoor wireless local area network. The initiating device exchanges FTM frames with the responding device and thereby receiving a first set of timestamps from the responding device. The initiating device receives a second set of timestamps associated with the exchanged FTM frames from one or more listening devices. Finally, the initiating device determines location information from the first and the second set of timestamps.

Abstract: A method is provided for sharing a communications channel in a wireless communications system. A network coordinating device of the wireless network obtains a first path quality information of each of a first set of one or more communications paths between a first pair of communications devices. The coordinating device also obtains a second path quality information of each of a second set of communications paths between a second pair of communications devices. The coordinating device then determines one or more co-existing communications paths based on the first and the second path quality information in accordance with a predetermined rule. Finally, the coordinating device sends channel resource allocation information to the first pair and the second pair of communications devices to use corresponding co-existing communications paths such that the first pair and the second pair of communications devices communicate over the communications channel during a period of time concurrently.

Abstract: A method of indoor positioning using Fine Timing Measurement (FTM) protocol with multi-antenna access point (AP) is proposed. In a wireless local area network, an AP has multiple antennas that are strategically located in different physical locations. The AP is used to exchange FTM frames with a wireless station for timing measurement of the FTM frames via its multiple antennas independently. The timing measurement result (e.g., timestamps of transmitting and receiving FTM frames) is then used to determine an absolute location of the station. A simplified Indoor Location operation with simplified deployment is achieved.

Abstract: A communication system is provided. A first communications device transmits at least one first message including predetermined bit sequences. A second communications device determines one or more antenna weighting vectors (AWVs) and one or more bitloading vectors (BLVs) by using the first message in accordance with a predetermined rule and transmits a second message including information pertinent to the AWVs and the BLVs to the first communications device. The first communications device further communicates with the second communications device about an AWV selected from the AWVs and the first and second communications devices apply the selected AWV to the corresponding antennas before exchanging data. The data includes a header carrying information pertinent to a BLV selected from the BLVs used to encode the data and a payload is transmitted to the second communications device. The second communications device decodes the data in accordance with the selected BLV.

Abstract: A communications system including communications devices is provided. A communications device, a trainer, generates at least one concatenated training sequence, transmits the at least one concatenated training sequence, and receives one or more response messages describing corresponding channel characteristics from at least one of the rest of the plurality of communications devices. One or more of the rest of the plurality of communications devices, trainees, each receives the at least one concatenated training sequence, determines channel characteristics between the trainer and a trainee according to the at least one received concatenated training sequence, embeds channel characteristics information to generate at least one of the response messages, and transmits the response message.

Abstract: A communication system includes a trainee communications device and one or more trainer communications devices. The trainee communications device announces a first period of time for beamforming training, switches a receiving antenna pattern to a sector and stays in the sector for a second period of time. The trainer communications devices transmit one or more predetermined bit sequences in the first period of time. The predetermined bit sequences are transmitted in at least one sector. Each of the predetermined bit sequences carries an identifier identifying the transmitting trainer communications device.

Abstract: A communication system includes a trainee communications device and one or more trainer communications devices. The trainee communications device announces a first period of time for beamforming training, switches a receiving antenna pattern to a sector and stays in the sector for a second period of time. The trainer communications devices transmit one or more predetermined bit sequences in the first period of time. The predetermined bit sequences are transmitted in at least one sector. Each of the predetermined bit sequences carries an identifier identifying the transmitting trainer communications device.

Abstract: A communication system is provided. A first communications device transmits at least one first message including predetermined bit sequences. A second communications device determines one or more antenna weighting vectors (AWVs) and one or more bitloading vectors (BLVs) by using the first message in accordance with a predetermined rule and transmits a second message including information pertinent to the AWVs and the BLVs to the first communications device. The first communications device further communicates with the second communications device about an AWV selected from the AWVs and the first and second communications devices apply the selected AWV to the corresponding antennas before exchanging data. The data includes a header carrying information pertinent to a BLV selected from the BLVs used to encode the data and a payload is transmitted to the second communications device. The second communications device decodes the data in accordance with the selected BLV.

Abstract: A communications system including communications devices is provided. A communications device, a trainer, generates at least one concatenated training sequence, transmits the at least one concatenated training sequence, and receives one or more response messages describing corresponding channel characteristics from at least one of the rest of the plurality of communications devices. One or more of the rest of the plurality of communications devices, trainees, each receives the at least one concatenated training sequence, determines channel characteristics between the trainer and a trainee according to the at least one received concatenated training sequence, embeds channel characteristics information to generate at least one of the response messages, and transmits the response message.

Abstract: A rate adaptation method for a wireless communication apparatus includes: determining whether to use a first mode or a second mode according to at least one estimation value, where the first mode and the second mode correspond to different values of an overall data rate of the wireless communication apparatus. A wireless communication apparatus for performing wireless communication with rate adaptation includes: a processing circuit; and a wireless receiver and a wireless transmitter, both coupled to the processing circuit. The processing circuit determines at least one estimation value regarding communication quality of the wireless communication apparatus, and further determines whether to use a first mode or a second mode according to the estimation value, where the first mode and the second mode correspond to different values of an overall data rate of the wireless communication apparatus.

Abstract: A transmission method is provided, whereby a first wireless device transmits an RF signal to a second wireless device using desired transmission power. First, the RF signal to be transmitted is provided. First parameters of the first wireless device are detected, as well as the second parameters of the second wireless device. Transmission power of the RF signal is then determined based on the first and second parameters, and the RF signal is accordingly amplified and output for transmission. Specifically, the second parameters may comprise an algorithm for decoding, and a number of receivers are in the second wireless device.

Abstract: A method is provided for sharing a communications channel in a wireless communications system. A network coordinating device of the wireless network obtains a first path quality information of each of a first set of one or more communications paths between a first pair of communications devices. The coordinating device also obtains a second path quality information of each of a second set of communications paths between a second pair of communications devices. The coordinating device then determines one or more co-existing communications paths based on the first and the second path quality information in accordance with a predetermined rule. Finally, the coordinating device sends channel resource allocation information to the first pair and the second pair of communications devices to use corresponding co-existing communications paths such that the first pair and the second pair of communications devices communicate over the communications channel during a period of time concurrently.

Abstract: An approach for decoding a substantially orthogonal code, such as a CCK code, based on its trellis diagram is provided. Compared to the conventional decoder based on codeword correlation, the unconventional decoder here has the advantage that it can work together with a decision feedback equalizer without suffering from the error propagation effect of the equalizer. In other words, the unconventional decoder makes joint decision feedback equalizer and decoder workable, which in turn enables reliable transmission of a signal encoded by a substantially orthogonal code over a multi-path channel.

Abstract: An approach for decoding a substantially orthogonal code, such as a CCK code, based on its trellis diagram is provided. Compared to the conventional decoder based on codeword correlation, the unconventional decoder here has the advantage that it can work together with a decision feedback equalizer without suffering from the error propagation effect of the equalizer. In other words, the unconventional decoder makes joint decision feedback equalizer and decoder workable, which in turn enables reliable transmission of a signal encoded by a substantially orthogonal code over a multi-path channel.