초록 ▼

A TDD antenna array S-CDMA system for increasing the capacity and quality of a wireless communications is disclosed. By simultaneous exploiting the spatial and code diversities, high performance communications between a plurality of remote terminals and a base station is achieved without sacrificing

A TDD antenna array S-CDMA system for increasing the capacity and quality of a wireless communications is disclosed. By simultaneous exploiting the spatial and code diversities, high performance communications between a plurality of remote terminals and a base station is achieved without sacrificing system flexibility and robustness. The time-division-duplex mode together with the inherent interference immunity of S-CDMA signals allow the spatial diversity to be exploited using simple and robust beamforming rather than demanding nulling. Measurements from an array of receiving antennas at the base station are utilized to estimate spatial signatures, timing offsets, transmission powers and other propagation parameters associated with a plurality of S-CDMA terminals. Such information is then used for system synchronization, downlink beamforming, as well as handoff management. In an examplary embodiment, the aforementioned processing is accomplished with minimum computations, thereby allowing the disclosed system to be applicable to a rapidly varying environment. Among many other inherent benefits of the present invention are large capacity and power efficiency, strong interference/fading resistance, robustness power control, and easy hand-off.

대표청구항 ▼

[ What is claimed is:] [1.] A time division duplex (TDD) antenna array synchronous code division multiple access (S-CDMA) communications system for communicating message data to/from a plurality of terminals, comprising:a multichannel transceiver array comprising a plurality of antennas and a plural

[ What is claimed is:] [1.] A time division duplex (TDD) antenna array synchronous code division multiple access (S-CDMA) communications system for communicating message data to/from a plurality of terminals, comprising:a multichannel transceiver array comprising a plurality of antennas and a plurality of transceivers, wherein said multichannel transceiver array is adapted for receiving combinations of multichannel uplink S-CDMA signals from said terminals and transmitting multichannel downlink S-CDMA signals towards said terminals, wherein said multichannel transceiver array is adapted for receiving said combinations of multichannel uplink S-CDMA signals from said terminals and transmitting multichannel downlink S-CDMA signals towards said terminals during different time frames in a time division duplex manner;a spatial processor coupled to said multichannel transceiver array for determining spatial signature estimates associated with said terminals from said combinations of multichannel uplink S-CDMA signals, wherein said spatial processor is also operable to calculate uplink and downlink beamforming matrices based on the spatial signature estimates;a demodulator coupled to said spatial processor and said multichannel transceiver array for determining estimates of uplink messages from said terminals from said combinations of multichannel uplink S-CDMA signals; anda modulator coupled to said multichannel transceiver array for generating said multichannel downlink S-CDMA signals to transmit messages destined for said terminals.