Universal demodulator

Abstract

The invention discloses a universal demodulator, comprising an interface, an interface circuit, an analog-to-digital converter and an FPGA chip, wherein the interface circuit comprises a hardware filter circuit, a voltage conversion circuit and a single-end-to-differential circuit, a demodulation algorithm module is constructed in the FPGA chip, the interface, the hardware filter circuit, the voltage conversion circuit, the single-end-to-differential circuit, the analog-to-digital converter and the FPGA chip are connected in sequence, the interface collects an intermediate frequency signal, the intermediate frequency signal is preprocessed by the interface circuit and is sent to the analog-to-digital converter, the analog-to-digital converter completes AD conversion on the intermediate frequency signal, and then a digital signal after the AD conversion is sent to the demodulation algorithm module of the FPGA chip for demodulation. According to the universal demodulator disclosed by theinvention, the interface circuit has universality on the bandwidth and the gain performance, thereby effectively preventing the amplitude of a circuit saturation signal from being too small, and ensuring the conversion precision of the analog-to-digital converter.

Description

technical field [0001] The present invention relates to a general demodulator. Background technique [0002] In foreign countries, discussions and reports on digital demodulation systems appeared in the 1980s, and digital demodulation design ideas based on System On Chip (SOC) and software radio technology gradually appeared after the 1990s. Some companies have launched digital demodulation products one after another. In 2007, Pentek of the United States successfully launched the powerful Model 7142-428 software radio processor, which not only includes 14-bit 125MHz 4 AD and 1 DA conversion channels, but also designs a multi-band digital down-conversion core , which can realize the extraction range of 2-65536, and also has an interpolation filter with an interpolation range of 2-32768; a series of software wireless processor products launched by Pentek provide superior solutions for wireless communication and other systems. In the research and development of signal generat...

AI Technical Summary

Problems solved by technology

However, the high cost of hundreds of thousands or millions is unbearable for test equipment, and it can only be used as experimental equipment.

Now some universities and companies in China have also begun to develop boards and equipment in this area, but the functions of such equipment are relatively single, and they can only work under fixed modulation and demodulation mode, symbol rate and carrier frequency

In the development of test equipment, for the different parameter requirements of test equipment, there is no universal and cost-effective modulation and demodulation test platform, and high-efficiency solutions for project design and development. Only the expensive foreign general-purpose models can be selected. Domestic modem boards with a single product or performance, in the process, the procurement cycle becomes longer and the product cost rises sharply, seriously affecting product development and delivery

At the same time, in such a development mode of modem test equipment, different test parameter requirements make the development parameters of test equipment different, making the development of each test equipment independent of each other, unable to form economies of scale, and difficult to master core technologies

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