8 results about "Rake receiver" patented technology

The invention relates to the technical field of spread spectrum communication, and discloses a channel equalization method for short-wave spread spectrum communication, which comprises the following steps: performing initial channel estimation and RAKE equalization according to a received complete receiving sequence to obtain an initial RAKE equalization result; performing channel decoding on the initial RAKE equalization result to obtain a decoding reconstruction sending sequence; and correcting channel estimation and RAKE equalization according to the decoding reconstruction sending sequence to obtain an RAKE equalization result for data decoding. According to the method, the error correction capability of channel coding can be fully utilized, and equalization errors caused by channel fading can be corrected. When deep fading occurs in a short-wave communication channel, the equalization accuracy of the RAKE receiver can be improved. The invention further discloses a channel equalization device for short-wave spread spectrum communication and the RAKE receiver.

The RAKE receiver signal synchronization detection method provided in the application comprises the following steps: sorting each correlation value in an initial correlation value set by a RAKE receiver to obtain a final correlation peak position set, selecting a first group of correlation value positions from the final correlation peak position set as a first correlation value position set, and selecting a second group of correlation value positions from the final correlation peak position set as a second correlation value position set; determining the initial position of each correlation value in the second correlation value position set, and selecting the associated position of each correlation value position to be detected based on the initial position to obtain an associated position set of each correlation value position; comparing the associated positions in each associated position set with the final correlation peak positions in the first correlation value position set to determine the number of paths; determining a synchronization detection position based on the number of paths, and processing the received signal based on the synchronization detection position. The synchronization performance under a low signal-to-noise ratio is improved.

The application discloses a signal receiving method for spread spectrum underwater acoustic communication of long-distance time-varying channel, which comprises the following steps: obtaining the received communication signal, carrying out down-conversion and low-pass filtering to obtain a baseband signal, and carrying out synchronization to divide the baseband signal into pilot signals and spread spectrum sequence signals; using the pilot signals to complete initial channel estimation to obtain initial Doppler estimation value, time delay and amplitude response estimation value of each path; using the estimated Doppler to carry out frequency offset compensation and resampling on the first spread spectrum sequence receiving signal; using the estimated time delay and amplitude response to construct a first to-be-estimated spread spectrum sequence signal Rake receiver; combining the Rake receiver and using maximum likelihood estimation to realize the decision of the current spread spectrum sequence and the log-likelihood ratio of each bit; using the decided spread spectrum sequence to estimate the Doppler, time delay and amplitude response of the current spread spectrum sequence signal; and in this way, the decision of all spread spectrum sequences is completed. The application can effectively reduce the demodulation error rate.

Methods, systems, and devices for wireless communications are described. The techniques described herein relate to user equipment (UE) reporting for a rake receiver configuration and setting transmission parameters. The UE receives, from a network entity, a request to provide a report indicative of one or more capability parameters associated with a rake receiver of the UE. The UE transmits, to the network entity, the report based on the one or more capability parameters. The UE receives from the network entity, signaling indicating a configuration to be applied to the rake receiver based at least in part on the report.

A method for dynamically adjusting the revisit rate of a rake receiver for an individual UE is disclosed, such that the time to initially acquire the UL transmission is optimized while the ongoing Central Processing Unit (CPU) loading during normal operation is minimized. The method may comprise operating a multipath searcher in a first mode of operation at a first time, the first mode being an acquisition mode, the multipath searcher operating with a revisit rate of 100 percent; and, operating the multipath searcher in a second mode of operation at a second time, the second mode being a steady-state mode and the multipath searcher operating with a revisit rate of less than 100 percent.

A method for dynamically adjusting the revisit rate of a rake receiver for an individual UE is disclosed, such that the time to initially acquire the UL transmission is optimized while the ongoing Central Processing Unit (CPU) loading during normal operation is minimized. The method may comprise operating a multipath searcher in a first mode of operation at a first time, the first mode being an acquisition mode, the multipath searcher operating with a revisit rate of 100 percent; and, operating the multipath searcher in a second mode of operation at a second time, the second mode being a steady-state mode and the multipath searcher operating with a revisit rate of less than 100 percent.

This invention discloses a signal receiving method for spread spectrum underwater acoustic communication in long-distance time-varying channels, comprising: acquiring the received communication signal, obtaining a baseband signal through down-conversion and low-pass filtering, and dividing the baseband signal into blocks according to pilot signals and spread spectrum sequence signals after synchronization; performing initial channel estimation using the pilot signals to obtain initial Doppler estimates, time delay estimates, and amplitude response estimates for each path; performing frequency offset compensation and resampling on the first spread spectrum sequence received signal using the estimated Doppler; constructing a Rake receiver for the first spread spectrum sequence signal to be estimated using the estimated time delay and amplitude response; combining the Rake receiver and using maximum likelihood estimation to realize the decision on the current spread spectrum sequence and the log-likelihood ratio of each corresponding bit; estimating the Doppler, time delay, and amplitude response of the current spread spectrum sequence signal using the decided spread spectrum sequence; and so on, completing the decision on all spread spectrum sequences. This invention can effectively reduce the demodulation bit error rate.

The invention relates to the technical field of wireless communication, and discloses a signal receiving method applied to DSSS-OQPSK and a differential rake receiver, and the method comprises the following steps: carrying out multipath separation on a received signal, and sequentially carrying out the following steps on each path: a, carrying out de-spreading processing based on a direct sequence spreading code, and generating a complex symbol sequence containing a phase error; b, performing conjugate differential operation on adjacent complex symbols to eliminate phase errors, and obtaining differential symbols after the phase errors are eliminated; combining the differential symbols after the phase errors are eliminated according to the receiving power of the paths where the differential symbols are located, wherein the receiving power is obtained through channel estimation (CE); and outputting the combined demodulation signal. According to the method, energy-based combination is carried out on differential symbols output by each path, and the method is not sensitive to frequency deviation, phase deviation and sampling deviation.