Application And Research About Single Bit Technology In Time Delay Estimation

Time delay estimation of wide-band signal is a basic problem in the field of signal processing,and it has an important application in underwater acoustic range finder.Usually,the A/D converter is used to quantify the received signal and transform it into a multi-bit digital signal,and then use the processor to copy the correlation operation,and further get the time delay estimation result.This method requires multiple multiplication and multiplication,which requires the hardware multiplier inside the processor and the complexity of the hardware.While the single bit quantization of signal processing technology,is receiving the signal to quantization for single digital signal characteristics,the operation does not require a multiplication,can significantly reduce the size of the hardware processor.This paper studies a kind of single bit signal processing technology based on delta-sigma modulation,the single bit quantization signal in the time domain directly copy related operations,significantly reduced the amount of calculation of single point.The main contents of the paper are as follows:First of all,this paper through theoretical research and simulation experiment for LFM and CW signals using acoustic ranging in the delay of the single bit correlator and multi-bit correlator estimation results are analyzed,and the single bit quantization sampling rate,order number on quantization noise is analyzed.Then,in order to test one bit correlator estimation performance,using FPGA as the processor,design the corresponding hardware verification platform,design the specific circuit structure of each module.Subsequently,the use of FPGA development environment for the preparation of the corresponding single correlator associated with multiple bits for the procedure,focuses on the analysis of the comparison of resources and power consumption in single bit quantization and multi-bit quantized signal copy correlation algorithm in the realization process.For the multi-bit quantized signal time correlation algorithm,eight bit or sixteen bit multiplication requires a huge amount of hardware resources,while the single bit quantization signal,each operation requires only one digit multiplication,can save a lot of multipliers.Without loss of time delay estimation accuracy under the premise of using the single signal processing technology with high operation frequency,in a "space for time" thought to reduce the computational complexity of the.Finally,the hardware verification platform is designed,and the LFM signal is taken as input signal.After quantizing by single bit ADC and multi-bit ADC,the related operations arecarried out respectively,and the result is output through DAC.The hardware verification proved that single bit correlator results correctly,by reducing the scale of hardware can significantly reduce the power consumption of the system.And the data analysis on the test of Lake Qiandao Lake single bit related processing,to verify the feasibility of single bit signal processing technology in the actual conditions.