2 results about "Time domain equalization" patented technology

The application provides a time domain adaptive equalization method based on bidirectional superimposed training sequence, which uses superimposed training sequence to improve the spectrum utilization of underwater acoustic communication and the tracking ability of time-varying underwater acoustic channel. The method uses linear superimposed structure at the transmitting end and optimizes the power distribution of training sequence and information symbol, and the receiving end uses forward and reverse adaptive time domain equalization parallel processing to construct a bidirectional iterative optimization framework. Meanwhile, the application designs a time domain symbol-by-symbol training sequence interference cancellation mechanism to eliminate the interference of superimposed training sequence on the underwater acoustic communication system. The application mainly uses superimposed training sequence to improve the spectrum utilization of the system, saves bandwidth compared with the traditional inserted training sequence mode, and uses symbol-by-symbol to eliminate the interference of superimposed training sequence on the system. The simulation results prove that the method can improve the performance of the underwater acoustic communication system.

Methods, systems, and devices for wireless communications are described. A wireless communications device may receive a waveform including both a first waveform comprising an orthogonal frequency division multiplexing (OFDM) waveform and a second waveform comprising a single-carrier waveform via a set of time-frequency resources. The wireless device may decode the first waveform based on receiving the waveform, where the first waveform includes one or more reference signals. The wireless communications device may decode the second waveform based on receiving the waveform and on a time domain equalization filter that is based on decoding the one or more reference signals, where the second waveform comprises a set of data bits. In some examples, the waveform may further include a third waveform including a second OFDM waveform and the wireless communications device may decode the third waveform including one or more second reference signals based on receiving the waveform.