摘要:
A radio communications system for performing communications based on an adaptive modulation by selecting one MCS from a set of MCSs each comprising a combination of a modulation scheme and a coding scheme which are ranked according to a transmission rate, the radio communications system comprising a change unit to change the selected MCS to a MCS of a higher ranking than the selected MCS when communication quality exceeds a first threshold, and change the selected MCS to a MCS of a lower ranking than the selected MCS when the communication quality is less than a second threshold lower than the first threshold, a first threshold controller to control the first threshold based on a first error rate, and a second threshold controller to control the second threshold based on a second error rate different from the first error rate.
摘要:
A receiver for receiving a CDMA signal comprises a common channel interference cancellation facility operable to cancel common channel interference by applying a common channel interference estimate to the received signal through a weighted hybrid of parallel and serial interference cancellation, and a physical channel self-interference cancellation facility operable to cancel physical channel self-interference by applying an interference estimate to the received signal through a weighted hybrid of parallel and serial interference cancellation.
摘要:
The present invention relates to wireless communication between a mobile terminal and a base station, and the use of interference cancellation in the uplink. The present invention is particularly but not exclusively concerned with 3G or UTRAN applications. In general terms the present invention provides a method of improving the performance of a CDMA based wireless network, such as a 3G cellular network for example. Interference cancellation is effectively performed earlier by using the channel request such as a reservation packet from a mobile terminal to estimate interference from that mobile on existing mobile users and interference on the mobile from existing mobile users, by determining the relative transmission timing of the new mobiles channel request compared with the transmission timings of the existing mobiles. This allows the base station to determine the cross-correlation between the codes already assigned to the existing users and the code to be allocated to the new user in order to determine an interference measure. This interference can then be cancelled from the new mobile when its data packets are received.
摘要:
A communication network comprises at least a first region serviced by a base station, and further comprises a plurality of bridging stations deployed around the base station so defining a circumference about said base station. Each bridging station comprises one or more directional antennas operable to generate a coverage area lying predominantly outside said circumference, so forming in operation an inner zone within said circumference wherein bridging station sensitivity and signal strength is significantly lower than that of the base station.
摘要:
A communication network comprises at least a first region serviced by a base station. This region also comprises a plurality of bridging stations deployed around the base station, so defining a circumference around it. Each bridging station comprises one or more directional antennas operable to generate a coverage area lying predominantly outside said circumference. The effect is to form, in operation, an outer zone predominantly outside said circumference serviced by said bridging stations, and an inner zone within said circumference serviced by said base station. For communications with the outer zone, said base station is operable to assign duplicate CDMA spreading codes to mobile stations in respective areas of the outer zone served by bridging stations that experience sufficiently low levels of cross-interference from each other's communications.