摘要:
A patch having a circular shape for instance is formed on the main surface of a substrate in the shape of, for example, an equilateral triangle. The center of the main surface of the patch is at a position different from the center of the substrate. A grounding conductor is disposed on the backside of the substrate. Power is supplied to the patch through, for example, a microstrip line, triplate line, coplanar waveguide, slot line or the like. An antenna configured as described above has the center of the patch at a position different from the center of the triangle substrate, so that beams can be tilted in a desired direction by a single patch and a single feeder circuit.
摘要:
An adaptive antenna is disclosed, that comprises a plurality of antenna elements 1.sub.1, 1.sub.2, . . . , and 1.sub.N with different directivity, delay profile measuring units 2.sub.1, 2.sub.2, . . . , and 2.sub.N for estimating states of received signals of the antenna elements for each of delay times that have been designated, antenna selecting units 3.sub.1, 3.sub.2, . . . , and 3.sub.L for selecting a part of the antenna elements for each of the delay times corresponding to the estimated result, adaptive signal processing portions 4.sub.1, 4.sub.2, . . . , and 4.sub.L for determining the received signals of the part of the antenna elements that have been selected and multiplying the received signals to which relevant weights have been determined for each of the delay time and summing the weighted signals, delaying circuits 5.sub.2 and 5.sub.3 for compensating the time lag, or delay of each of the received signals for each of the delay times, and a combining unit 6 for combining the weighted signals that have been compensated for the delay times.
摘要:
In a radio communication apparatus, delay profiles of a desired wave and delay waves thereof are estimated by plural delay profile estimation sections for each of received signals from directional antennas constituting an array antenna. Received signals from the antennas selected by a reception antenna selector on the basis of the delay profile are subjected to a temporal/spatial equalization processing by an adaptive signal processing section and a path diversity combining section, thereby obtaining a reception output. An arrival angle range of the desired wave is estimated by a DOA estimation section from the delay profile estimated by the delay profile estimation section. Based on the arrival angle range, the antenna for transmission is selected by a transmission antenna selection section, and transmission signals are sent out.
摘要:
In a radio communication apparatus, delay profiles of a desired wave and delay waves thereof are estimated by plural delay profile estimation sections for each of received signals from directional antennas constituting an array antenna. Received signals from the antennas selected by a reception antenna selector on the basis of the delay profile are subjected to a temporal/spatial equalization processing by an adaptive signal processing section and a path diversity combining section, thereby obtaining a reception output. An arrival angle range of the desired wave is estimated by a DOA estimation section from the delay profile estimated by the delay profile estimation section. Based on the arrival angle range, the antenna for transmission is selected by a transmission antenna selection section, and transmission signals are sent out.
摘要:
There is disclosed a radio communication system in which a constitution of a base station and further a control station can be simplified. A radio communication system according to the present invention converts a received signal received by a plurality of antenna elements in a base station to a signal of different frequency band, and then conflates the converted signal in order to generate sub-carrier wave multiplex signal. The signal is converted to an optical signal, and then the optical signal is transmitted to a control station via an optical fiber. Or the control station performs weighting to phase of the transmitted signal transmitted from a plurality of antennas of a base station, and then performs frequency conversion to different frequency band, and then conflates the converted signal in order to generate the sub-carrier wave multiplex signal. The signal is converted to an optical signal, and then an optical signal is transmitted to the base station side via the optical fiber. The control station and the base station divides the received sub-carrier wave multiplex signal by each frequency band, and then the frequency of the divided signals are converted to the same frequency band in order to generate the transmitted/received signal of each antenna element. By such a constitution, it is possible to reduce constituent of the optical transmission components to the minimum and to simplify the constitution of the base station. Furthermore, it is possible to maintain the relative phase difference and the relative intensity of the transmitted/received signal of each antenna element. Because of this, it is possible to estimate an arrival direction of the received signal and to control radiation beam pattern of the transmitted signal.
摘要:
A diversity receiver device includes N antennas to receive OFDM signals, N digital filters to filter the signals received by the N antennas in order to reduce delay spread, K (K≦N) beamforming units configured to subject the filtered signals to a beamforming process by using combining weights, an eigen-decomposition unit configured to subject the filtered signals to eigen-decomposition to generate N eigenvalues, a weight setting unit configured to select K eigenvalues in descending order from the generated N eigenvalues in order to set eigenvectors corresponding to the K eigenvalues to the beamforming units as the combing weight, respectively, K FFT units configured to subject the output signals of the beamforming units to fast Fourier transformation to output FFT signals, and a diversity combining unit configured to combine the FFT signals.
摘要:
There is disclosed a radio communication system in which a constitution of a base station and further a control station can be simplified. A radio communication system according to the present invention converts a received signal received by a plurality of antenna elements in a base station to a signal of different frequency band, and then conflates the converted signal in order to generate sub-carrier wave multiplex signal. The signal is converted to an optical signal, and then the optical signal is transmitted to a control station via an optical fiber. Or the control station performs weighting to phase of the transmitted signal transmitted from a plurality of antennas of a base station, and then performs frequency conversion to different frequency band, and then conflates the converted signal in order to generate the sub-carrier wave multiplex signal. The signal is converted to an optical signal, and then an optical signal is transmitted to the base station side via the optical fiber. The control station and the base station divides the received sub-carrier wave multiplex signal by each frequency band, and then the frequency of the divided signals are converted to the same frequency band in order to generate the transmitted/received signal of each antenna element. By such a constitution, it is possible to reduce constituent of the optical transmission components to the minimum and to simplify the constitution of the base station. Furthermore, it is possible to maintain the relative phase difference and the relative intensity of the transmitted/received signal of each antenna element. Because of this, it is possible to estimate an arrival direction of the received signal and to control radiation beam pattern of the transmitted signal.
摘要:
There is disclosed a radio communication system in which a constitution of a base station and further a control station can be simplified. A radio communication system according to the present invention converts a received signal received by a plurality of antenna elements in a base station to a signal of different frequency band, and then conflates the converted signal in order to generate sub-carrier wavemultiplex signal. The signal is converted to an optical signal, and then the optical signal is transmitted to a control station via an optical fiber. Or the control station performs weighting to phase of the transmitted signal transmitted from a plurality of antennas of a base station, and then performs frequency conversion to different frequency band, and then conflates the converted signal in order to generate the sub-carrier wave multiplex signal. The signal is converted to an optical signal, and then an optical signal is transmitted to the base station side via the optical fiber. The control station and the base station divides the received sub-carrier wave multiplex signal by each frequency band, and then the frequency of the divided signals are converted to the same frequency band in order to generate the transmitted/received signal of each antenna element. By such a constitution, it is possible to reduce constituent of the optical transmission components to the minimum and to simplify the constitution of the base station. Furthermore, it is possible to maintain the relative phase difference and the relative intensity of the transmitted/received signal of each antenna element. Because of this, it is possible to estimate an arrival direction of the received signal and to control radiation beam pattern of the transmitted signal.
摘要:
Orthogonal frequency division multiplexing demodulation apparatus includes: antenna to receive signal including holding period including part of period ranging from leading portion of delayed wave of maximum-delay time to trailing portion of preceding wave, unit estimating channel response of signal received by antenna, unit holding, based on channel response, first-signal component contained in holding period, first-signal component including second-signal component which is contained in period of preset length which is included in holding period, unit acquiring filter-bank outputs by subjecting second-signal component to frequency conversion, unit generating replicas for each of filter-bank outputs, based on estimated-channel response, frequency response of each of filter-bank outputs, and candidates for modulation signal corresponding to subcarrier included in each of filter-bank outputs, unit selecting one of replicas which minimizes quantity corresponding to differences between components of each of filter-bank outputs and components of replicas, and unit determining modulation signal based on selected replica.
摘要:
Orthogonal frequency division multiplexing demodulation apparatus includes: antenna to receive signal including holding period including part of period ranging from leading portion of delayed wave of maximum-delay time to trailing portion of preceding wave, unit estimating channel response of signal received by antenna, unit holding, based on channel response, first-signal component contained in holding period, first-signal component including second-signal component which is contained in period of preset length which is included in holding period, unit acquiring filter-bank outputs by subjecting second-signal component to frequency conversion, unit generating replicas for each of filter-bank outputs, based on estimated-channel response, frequency response of each of filter-bank outputs, and candidates for modulation signal corresponding to subcarrier included in each of filter-bank outputs, unit selecting one of replicas which minimizes quantity corresponding to differences between components of each of filter-bank outputs and components of replicas, and unit determining modulation signal based on selected replica.