Signal generator and wavetable recombination method thereof

Abstract

The invention provides a signal generator and a wavetable recombination method thereof. The signal generator comprises a CPU, a field programmable gate array (FPGA), an external waveform memory, a digital analog conversion chip and an analog circuit. The field programmable gate array is connected to the CPU through a CPU interface. The external waveform memory is connected with an external storage controller of the FPGA. The external waveform memory comprises a user wavetable storage module and a buffer wavetable storage module. The user wavetable storage module is used for storing a user wavetable. The FPGA comprises a work mode determination module which is in the CPU and is used for determining whether a work mode of a random wave is a pumping point mode or not, and a wavetable recombination module which is connected with the CPU interface and controls the external storage controller to draw a wavetable from the user wavetable storage module and outputs a stored wavetable. According to the signal generator and the wavetable recombination method, an output frequency scope and frequency precision of a large wavetable random wave are raised.

Description

technical field [0001] The present invention relates to signal processing technology, in particular to signal generator technology, and specifically to a direct digital synthesis (Direct Digital Synthesis DDS) method. Background technique [0002] At present, there are many types of memory on the market, mainly volatile RAM and DRAM, non-volatile EEPROM, ROM, EPROM, NOR, NAND flash memory, ferroelectric memory (FeRAM) and emerging magnetic memory (MRAM). When applying a signal generator, it is necessary to select an appropriate memory. [0003] SRAM has rich access interfaces, simple control, and fast access speed; but its basic unit is usually composed of 4 to 6 transistors, and the cost is very high, especially when the signal source requires a large-capacity arbitrary wave, the cost is particularly difficult. accept. [0004] Some field programmable gate array FPGA-based signal source products use embedded memory units as waveform memory, such as field programmable gate...

AI Technical Summary

Problems solved by technology

The above-mentioned signal generator can only meet the requirements of high sampling rate output by reading DRAM point by point. In the case of a large wave table length, it cannot output higher frequency waveforms.

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