Multicarrier communication system
Improving channel response characteristics between a transmitter and a receiver, in a Multiple-Input-Multiple-Output (MIMO)-system without increasing the number of receiving antennas, by using fractional sampling in a receiver, delaying and transmitting part of plural transmitting signals demodulating data of the plural data series.
1. A multi-carrier communications system, comprising:
a transmitter that transmits plural data series by the same subcarrier from plural antennas and a receiver that receives the plural data series with plural antennas; wherein:
the transmitter transmits the plural data series with a transmitting pulse period [−Ts, Ts], and a multiplicity of transmitting signal Mt, and includes a means for delaying the k-th (2<=K<=Mt) transmitting signal of a part series of the plural data series for Ts(K−1)/Mt from the first transmitting signal and transmitting from the plural antennas, and
the receiver includes a means for receiving the signals transmitted from the transmitter with each antenna of the one or plural antennas and performing fractional sampling to the received signals, and a means for demodulating data of the plural data series obtained by the fractional sampling.
2. The multi-carrier communications system as set forth in claim 1 , said receiver includes:
a means for judging good or bad of qualities of channel response characteristics of received multi-carrier signals, and
a means for indicating to the transmitter to transmit signals after delaying signals for the predetermined time based on a judgment of the means for judging.
3. The multi-carrier communications system as set forth in claim 1 , said receiver includes:
a means for transmitting data about channel response characteristics of received multi-carrier signals to the transmitter,
a means for judging qualities of the channel response characteristics based on the data about the channel response characteristics that the receiver transmitted, and
a means for delaying signals for the predetermined time based on a judgment of the means for judging.
4. The multi-carrier communications system as set forth in claim 1 , said receiver includes:
a means for determining a necessary amount of delay by the channel response characteristics of a received multi-carrier signal, and
a means for indicating to the transmitter to delay and transmit signals based on the judged amount.
5. The multi-carrier communications system as set forth in claim 1 , said receiver includes:
a means for transmitting a data about channel response characteristics of a received multi-carrier signal to the transmitter,
a means for determining a necessary amount of delay by the channel response characteristics that the receiver transmitted, and
a means for delaying a transmission of signals based on the determined amount of delay.