摘要:
A method to improve the area throughput of dense wireless local area networks (WLAN) by channel access control is proposed. The method allows an access point to obtain information of a plurality of stations within the wireless network. The access point classifies the plurality of stations into at least one group of stations and assigns a group identification (ID) according to the obtained information. The group ID and channel access control parameters are sent to the stations that are classified into the certain group. The stations in each of the group use the received channel access control parameters to communicate with the access point.
摘要:
A method of sounding and feedback with channel quality information and reduced overhead is provided. A receiving station receives a sounding signal transmitted from an access point over multiple sub-channels of a wide channel in a wireless network. The receiving station detects channel quality based on the received sounding signal for each sub-channel. The receiving station then performs channel estimation based on the received sounding signal and thereby determining feedback information. Finally, the receiving station transmits a feedback message to the access point, the feedback message contains NULL feedback information, reduced feedback information, or channel integrity/quality indicators based on the channel quality information for each sub-channel. Based on the feedback message, the access point may repeat the sounding process, narrow the transmission bandwidth, or select only stations who have indicated uncorrupted channel sounding for MU-MMO transmission.
摘要:
An open-loop fast link adaptation scheme is proposed in an OFDM system. An access point first transmits a downlink packet comprising an open-loop link metric to a wireless station. The open-loop link metric contains a transmit power of the downlink packet plus a receiver sensitivity of the access point. The wireless station measures a received signal strength indication (RSSI) value of the downlink packet. The wireless station then applies open-loop link adaptation and determines a modulation and coding scheme (MCS) based on the open-loop link metric and the RSSI value. The open-loop link adaptation scheme is especially suitable for smart meter/sensor networks as it reduces overhead and increases link capacity.
摘要:
A radio frequency (RF) transmitter is coupled to and controlled by a processor to transmit data. A physical layer circuit is coupled to the RF transmitter to encode and decode between a digital signal and a modulated analog signal. The physical layer circuit comprises a high rate physical layer circuit (HRP) and a low rate physical layer circuit (LRP). The low rate channels generated by the low rate physical layer circuit (LRP) share a same frequency band as a corresponding high rate channel generated by the high rate physical layer circuit (HRP).