Path division multiple access radio apparatus having directivity control based on received radio strength
AssigneeSanyo Electric Co., Ltd.
InventorsYoshiharu Doi, Toshinori Iinuma
Life of this patent
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Abstract
An adaptive array multiplies a radio signal received in four antennas by a received weight vector thereby separating a signal from each user. On the basis of the received signal and the received weight vector, a received power measuring circuit derives radio signal strength from each terminal. A transmit weight vector control part controls a transmit weight vector in response to the receive radio signal strength, i.e., the distance between a base station and each terminal, and reduces undesired interference with another cell by adjusting transmission power.
Claims10
A radio apparatus comprising:
- a receiver, having receiving directivity for performing path division multiple access with a plurality of terminal units, for separating a received signal from one of said terminal units from a received radio signal, said receiver including:
- a plurality of received signal separators multiplying said received radio signal by a received weight vector corresponding to each said terminal unit thereby extracting said received signal, and
- received strength measuring means for measuring received radio strength of each said terminal unit;
- and
- a transmitter, having transmission directivity for performing said path division multiple access, for generating a transmit signal having directivity to said specific terminal unit, said transmitter including:
- a plurality of transmit signal generators multiplying a transmit signal by a transmit weight vector obtained by weighting said received weight vector for each said terminal unit in response to said received radio strength from said received radio strength measuring means thereby generating said transmit signal having directivity,
- wherein said received radio strength from said received radio strength measuring means corresponds to all the terminal units accessing said radio apparatus through said path division multiple access.
A method of controlling a radio apparatus having transmission directivity for performing path division multiple access with a plurality of terminal units, comprising steps of:
- deriving a received weight vector corresponding to each said terminal unit in real time and separating a received signal from said terminal unit;
- measuring received radio strength of each said terminal unit on the basis of a received radio signal and said separated received signal;
- deriving a transmit weight vector obtained by weighting said received weight vector in response to said received radio strength corresponding to all the terminal units accessing said radio apparatus through said path division multiple access;
- and
- multiplying a transmit signal by said transmit weight vector thereby generating a transmit signal having directivity.
Dependencies are inferred from the claim text.