RECEIVING DEVICE, RECEIVING METHOD, PROGRAM AND WIRELESS COMMUNICATION SYSTEM

• US 20100095180A1
• Filed: 09/14/2009
• Published: 04/15/2010
• Est. Priority Date: 10/10/2008
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: SAWAI, Ryo
• Granted Patent: US 8,250,422 B2
• Time in Patent Office: Days
• US Class Current: 714/746
• CPC Class Codes: H04L 1/0048 in conjunction with detection of multiuser or interfering signals, e.g. iteration between CDMA or MIMO detector and FEC decoder for spatial equalizer H04L25/03286

Abstract

A receiving device is provided that includes a radio receiving unit to receive radio signals transmitted from multiple transmitting antennas by multiple receiving antennas and output received signals being digital signals, a frequency control unit to detect and correct a frequency error contained in the received signals, a channel estimation unit to estimate a channel matrix of which each element corresponds to respective pair of each transmitting antenna and each receiving antenna, an equalization unit to equalize the received signals by using the estimated channel matrix, a demodulation and decoding unit to demodulate and decode the equalized received signals, and an error estimation unit to estimate a channel variation component indicating temporal variation of characteristics of each channel and a phase error component remaining in the received signals based on the channel matrix, the received signals, and a decoding result or an equalization result.

Claims

1. A receiving device comprising:

a radio receiving unit to receive radio signals transmitted from a plurality of transmitting antennas by a plurality of receiving antennas and output received signals being digital signals;

a frequency control unit to detect a frequency error contained in the received signals and correct the frequency error;

a channel estimation unit to estimate a channel matrix of which each element corresponds to respective pair of each transmitting antenna and each receiving antenna;

an equalization unit to equalize the received signals by using the channel matrix estimated by the channel estimation unit;

a demodulation and decoding unit to demodulate and decode the received signals equalized by the equalization unit; and

an error estimation unit to estimate a channel variation component indicating temporal variation of characteristics of each channel and a phase error component remaining in the received signals based on the channel matrix, the received signals, and a decoding result by the demodulation and decoding unit or an equalization result by the equalization unit.

2. The receiving device according to claim 1, wherein the error estimation unit calculates the channel variation component and the phase error component by creating a sufficient number of relational expressions between the received signals and the decoding result or the equalization result for calculating the channel variation component and the phase error component with use of a plurality of receiving symbols and solving the created relational expressions.

3. The receiving device according to claim 1, wherein the error estimation unit calculates the channel variation component and the phase error component according to a recursive least square algorithm or a least mean square algorithm with use of the channel matrix, the received signals, and the decoding result or the equalization result.

4. The receiving device according to claim 1, wherein the error estimation unit outputs weighted averages of the channel variation component and the phase error component calculated for a plurality of times.

5. The receiving device according to claim 1, wherein the equalization unit equalizes the received signals by further using the channel variation component estimated by the error estimation unit.

6. The receiving device according to claim 1, wherein the frequency control unit further corrects phases of the received signals by using the phase error component estimated by the error estimation unit.

7. The receiving device according to claim 1, wherein the frequency control unit further corrects an error of a phase due to clock deviation based on the amount of change between subcarriers in the phase error component estimated by the error estimation unit.

8. The receiving device according to claim 1, wherein the error estimation unit further estimates an amplitude error component remaining in the received signals based on the channel matrix, the received signals, and the decoding result or the equalization result.

9. The receiving device according to claim 8, wherein the demodulation and decoding unit corrects an amplitude of the equalization result by the equalization unit by using the amplitude error component estimated by the error estimation unit.

10. A method for receiving radio signals in a receiving device, comprising the steps of:

receiving radio signals transmitted from a plurality of transmitting antennas by a plurality of receiving antennas and outputting received signals being digital signals;

detecting a frequency error contained in the received signals and correcting the frequency error;

estimating a channel matrix of which each element corresponds to respective pair of each transmitting antenna and each receiving antenna;

equalizing the received signals by using the estimated channel matrix;

demodulating and decoding the equalized received signals; and

estimating a channel variation component indicating temporal variation of characteristics of each channel and a phase error component remaining in the received signals based on the channel matrix, the received signals, and a decoding result or an equalization result.

11. A program causing a computer controlling a receiving device comprising:

a radio receiving unit to receive radio signals transmitted from a plurality of transmitting antennas by a plurality of receiving antennas and output received signals being digital signals;

a frequency control unit to detect a frequency error contained in the received signals and correct the frequency error;

a channel estimation unit to estimate a channel matrix of which each element corresponds to respective pair of each transmitting antenna and each receiving antenna;

an equalization unit to equalize the received signals by using the channel matrix estimated by the channel estimation unit; and

a demodulation and decoding unit to demodulate and decode the received signals equalized by the equalization unit,

to function as an error estimation unit to estimate a channel variation component indicating temporal variation of characteristics of each channel and a phase error component remaining in the received signals based on the channel matrix, the received signals, and a decoding result by the demodulation and decoding unit or an equalization result by the equalization unit.

12. A wireless communication system comprising:

a transmitting device to transmit radio signals from a plurality of transmitting antennas; and

a receiving device including;

a radio receiving unit to receive the radio signals by a plurality of receiving antennas and output received signals being digital signals,

a frequency control unit to detect a frequency error contained in the received signals and correct the frequency error,

a channel estimation unit to estimate a channel matrix of which each element corresponds to respective pair of each transmitting antenna and each receiving antenna,

an equalization unit to equalize the received signals by using the channel matrix estimated by the channel estimation unit,

a demodulation and decoding unit to demodulate and decode the received signals equalized by the equalization unit, and

an error estimation unit to estimate a channel variation component indicating temporal variation of characteristics of each channel and a phase error component remaining in the received signals based on the channel matrix, the received signals, and a decoding result by the demodulation and decoding unit or an equalization result by the equalization unit.