Full-Duplex Self-Interference Channel Estimation via Sparse Reference Signals
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Solution Overview
Problem
Current full-duplex communication systems face inefficiencies in channel estimation due to the slow frequency domain variation of self-interference channels, leading to increased time-frequency resources for data transmission.
Innovation Solution
A method for acquiring channel responses of self-interference channels in full-duplex communication devices involves transmitting reference signals at specific frequency points with intervals less than coherence time and bandwidth, determining stable frequency intervals, selecting optimal transmission frequency points, and calculating channel responses using interpolation in both time and frequency domains.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If reference signals are transmitted at all frequency points for channel estimation, then channel estimation precision is improved, but time-frequency resources for data transmission are reduced
Solution Approach 1:
The patent applies partial action by transmitting reference signals at only a subset of frequency points rather than all frequency points. Specifically, reference signals are transmitted at first, second, and third frequency points within a bandwidth, and channel responses at fourth frequency points are obtained through interpolation instead of direct measurement. This reduces the number of reference signal transmissions while maintaining acceptable channel estimation precision.
Solution Approach 2:
The patent uses interpolation to copy or estimate channel responses at frequency points where reference signals are not transmitted. The channel response at a fourth frequency point is calculated by interpolating between channel responses at surrounding frequency points (e.g., using linear interpolation: Hr(i) = (Hr(i-1) + Hr(i+1)) / 2). This creates a complete channel response profile without requiring direct measurement at every frequency point.
2Measurement precision
If reference signals are transmitted frequently in time domain, then channel estimation accuracy is improved, but reference signal resources are consumed
Solution Approach 1:
The patent reduces reference signal resources by transmitting reference signals at only certain frequency points and using interpolation for others. This partial measurement approach maintains channel estimation accuracy while consuming fewer reference signal resources compared to transmitting reference signals at all frequency points.
Solution Approach 2:
The patent performs preliminary channel estimation at a reduced set of frequency points, then uses interpolation to derive complete channel responses. This preliminary action at select frequency points suffices to reconstruct the full channel characteristics, avoiding the need for exhaustive reference signal transmissions.
Data Source
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AI summary
The present invention is applicable in the technical filed of communications. Provided are a method and full-duplex communication device for acquiring a channel response of a self-interfering channel. The method comprises: first, employing multiple reference signals to perform a channel estimation on the self-interfering channel, acquiring a channel response estimated value of the self-interfering channel, where the time intervals between adjacent reference signals are less than a related time of the self-interfering channel, and where the frequency-domain intervals between the adjacent reference signals are less than a related bandwidth of the self-interfering channel, then, determining a stable range of each channel frequency-domain response on the basis of the channel response estimated value, and then randomly selecting a frequency point within the stable range of each channel frequency-domain response or selecting a frequency point of a greater channel response to serve as an emission frequency point of the reference signals, and, when an interrelation of the channel responses on the emission frequency point and on a non-emission frequency point is acquired, acquiring all of the channel responses on time-domain and frequency-domain directions on the basis of a reception signal corresponding to the reference signals on the emission frequency point. The present invention conserves reference signal resources used for estimation of the self-interfering channel.