Receiving apparatus for receiving signals through adaptive array antenna
View Patent ↗Preceding filters receive the inputs of a plurality of received signals associated respectively with a plurality of antennas. Subsequent filters band-limit the plurality of inputted received signals, respectively. A first combining unit derives a weight vector for the plurality of band-limited received signals and performs array synthesis on the plurality of band-limited received signals, using the derived weight vector. The second combining unit performs array synthesis on the plurality of inputted received signal signals, using the derived weight vector. A demodulator demodulates the array-synthesis result.
1. A receiving apparatus comprising:
an input unit configured to receive a plurality of received signals corresponding respectively to a plurality of antennas;
a band limiting unit configured to band-limit the plurality of received signals, respectively, received from said input unit;
a first combining unit configured to derive a weight vector for the plurality of received signals which have been band-limited by said band limiting unit and configured to perform array synthesis on the plurality of received signals which have been band-limited by said band limiting unit, using the derived weight vector;
a second combining unit configured to perform array synthesis on the plurality of received signals received from said input unit, using the weight vector derived by said first combining unit; and
an output unit configured to output an array-synthesis result in said second combining unit;
a measurement unit configured to measure an interference power in a band adjacent to a desired band of the array-synthesis result to be outputted from said output unit; and
a regulating unit configured to adjust the bandwidth of said band limiting unit, according to the interference power measured by said measurement unit.
2. A receiving apparatus comprising:
an input unit configured to receive a plurality of received signals corresponding respectively to a plurality of antennas;
a band limiting unit configured to band-limit the plurality of received signals, respectively, received from said input unit;
a first combining unit configured to derive a weight vector for the plurality of received signals which have been band-limited by said band limiting unit and configured to perform array synthesis on the plurality of received signals which have been band-limited by said band limiting unit, using the derived weight vector;
a signal delay unit configured to delay the plurality of received signals, respectively, received from said input unit;
a second combining unit configured to perform array synthesis on the plurality of received signals delayed by said signal delay unit, using the weight vector derived by said first combining unit; and
an output unit configured to output an array-synthesis result in said second combining unit;
a vector delay unit configured to delay the weight vector derived by said first combining unit;
a selector configured to select either the delayed weight vector delayed by said vector delay unit or the weight vector derived by said first combining unit and configured to output the selected weight vector to said second combining unit; and
a control unit configured to control the selection made by said selector, based on convergence degree of the weight vector derived by said first combining unit,
wherein the amount of delay in said vector delay unit is smaller than that in said signal delay unit.
3. A receiving apparatus according to claim 2 , further comprising a monitoring unit configured to monitor error between a synthesis result in said first combining unit and a reference signal, as the convergence degree of the weight vector derived by said first combining unit,
wherein when the error monitored by said monitoring unit becomes less than a threshold value, said control unit has said selector select the weight vector derived by said first combining unit.
4. A receiving apparatus according to claim 3 , wherein when a predetermined period of time elapses after said control unit has had said selector select the weight vector derived by said first combining unit, said control unit has said selector select the weight vector delayed by said vector delay unit.
5. A receiving apparatus, comprising:
an input unit configured to receive a plurality of received signals corresponding respectively to a plurality of antennas, the received signals being such that Orthogonal Frequency Division Multiplexing (OFDM) signals and Frequency Modulation (FM) signals are subjected to frequency-division multiplexing;
a first conversion unit configured to convert the plurality of received signals, respectively, received from said input unit into frequency domain;
an insertion unit configured to insert zero into a subcarrier that differs from a subcarrier to which a known signal is assigned, for each of the plurality of received signals which have been converted by said first conversion unit, wherein the known signal is assigned to a subcarrier of a part of OFDM signal in each of the plurality of received signals which have been converted by said first conversion unit;
a second conversion unit configured to convert the plurality of received signals, respectively, to which zeros are inserted by said insertion unit, into time domain;
a first combining unit configured to derive a weight vector for the plurality of received signals which have been converted by said second conversion unit and configured to perform array synthesis on the plurality of received signals which have been converted by said second conversion unit, using the derived weight vector;
a second combining unit configured to perform array synthesis on the plurality of received signals received from said input unit, using the weight vector derived by said first combining unit; and
an output unit configured to output an array-synthesis result in said second combining unit.
6. A receiving apparatus according to claim 5 , wherein, in each of the plurality of received signals received from said input unit, a first OFDM signal is assigned to a low-frequency side of the FM signal and a second OFDM signal is assigned to a high-frequency side thereof, and
wherein, for each of the plurality of received signals, said insertion unit inserts zero into a subcarrier, in the first OFDM signal, differing from a subcarrier to which the known signal is assigned, inserts zero to a subcarrier corresponding to the FM signal, and inserts zero into a subcarrier, in the second OFDM signal, differing from a subcarrier to which the known signal is assigned.
7. A receiving apparatus, comprising:
a plurality of antennas;
a first conversion unit configured to convert a plurality of received signals corresponding respectively to said plurality of antennas, into frequency domain, respectively, the received signals being such that Orthogonal Frequency Division Multiplexing (OFDM) signals and Frequency Modulation (FM) signals are subjected to frequency-division multiplexing;
an insertion unit configured to insert zero into a subcarrier that differs from a subcarrier to which a known signal is assigned, for each of the plurality of received signals which have been converted by said first conversion unit, wherein the known signal is assigned to a subcarrier of a part of OFDM signal in each of the plurality of received signals which have been converted by said first conversion unit;
a second conversion unit configured to convert the plurality of received signals, respectively, to which zeros are inserted by said insertion unit, into time domain;
a first combining unit configured to derive a weight vector for the plurality of received signals which have been converted by said second conversion unit and configured to perform array synthesis on the plurality of received signals which have been converted by said second conversion unit, using the derived weight vector;
a second combining unit configured to perform array synthesis on the plurality of received signals corresponding respectively to the plurality of antennas, using the weight vector derived by said first combining unit; and
an output unit configured to output an array-synthesis result in said second combining unit.