Hong Kong Applied Science and Technology Research Institute Company, Limited

Vincent Lau

Soung Liew

Yan Wang

Meixia Tao

Sammy Ming Kit Chau

Kent Chen

Cheong-Yui Wong

Pui Bill Wong

Some representative embodiments are directed to controlling access to a wireless medium using 'credit' periods and 'free' periods. During a credit period, credits are initially assigned to the stations and each station is repetitively polled as long as the station has credit remaining and data is available to communicate. During the free periods, stations are polled using a start-time fair queuing algorithm. By dividing the access to the wireless medium in this manner, real time applications may use the credit periods to prevent communication latency from deteriorating application performance. Specifically, the repetitive occurrence of the credit periods and the assignment of credits to the stations ensures that each station will communicate at least at a minimum data rate. Additionally, controlling access to the wireless medium in this manner prevents frame collisions and, thereby, increases network throughput.

System and method for controlling access to a wireless medium

Disclosed are systems and methods which provide a busy tone or signal for use in communication collision avoidance in a wireless network, such as a WLAN, a cellular network, or other point-to-multipoint wireless network. An intelligent busy tone generator, upon the proper conditions, transmits a busy tone or signal to one or more wireless device which may otherwise be hidden from particular communications. According to embodiments the busy tone mimics a carrier sequence of an actual transmission to facilitate the wireless devices recognizing the channel as busy. Because the original uplink packet may be interfered by transmission of a busy tone carrier-sense sequence, embodiments are provided with interference cancellation capability. Interference cancellation circuitry of embodiments may operate in a plurality of modes, including a training mode (including an online training mode, an offline training mode, and a hybrid or combined mode) and an operating mode.

Busy tone for wireless networks

Disclosed are systems and methods which provide high bandwidth data communication with respect to a large coverage area using smart antenna and/or directional antenna techniques. Embodiments provide extended wireless local area network (WLAN) coverage areas using a directional antenna, with the cooperation of a cellular system or proprietary WLAN infrastructure to perform best antenna beam pattern estimation and signaling. Stations disposed beyond a WLAN coverage area may establish contact and exchange signaling information with an access point through a secondary control channel. Such a secondary control channel signaling may be relatively low bandwidth and may be utilized to identify the need to communicate data, to identify a 'best' directional antenna beam through which to communicate data, etcetera. Payload data may then be transmitted at a high bit rate through one or more smart antenna beams targeted at the appropriate stations.

Systems and methods for wireless network range extension

Growing community of inventors

Hong Kong, China

Vincent Lau