Multi-channel high-speed synchronous acquisition and quadrature modulation system

Abstract

The invention discloses a multi-channel high-speed synchronous sampling and quadrature modulation system which comprises a channel module and a digital processing module. The channel module and the digital processing module are connected. The digital processing module comprises a modulating circuit. A modulating circuit interface is connected with the channel module. The channel module comprises at least two radio frequency input channels with signal amplifying and filtering functions and at least one radio frequency output channel. The digital processing module comprises a single-plate-mounted FPGA module which is connected with an AGC control interface. An FPGA is connected with an analog-digital conversion module. The FPGA module is connected with a DSP with a CAN bus function. The FPGA is connected with a clock module. According to the system, multi-channel synchronous sampling and high-speed undersampling functions can be achieved, meanwhile, the functions of quadrature modulation, sampling signal level controlling and power supply protecting are achieved, and the multi-channel high-speed synchronous sampling and quadrature modulation system has the advantages of being high in accuracy, good in real-time performance, high in channel selectivity, adjustable in sampling rate, capable of working in a high-noise-interference environment and the like.

Description

technical field [0001] The invention relates to a signal acquisition and modulation device, in particular to a multi-channel high-speed synchronous acquisition and orthogonal modulation system. Background technique [0002] AGC is Automatic Gain Control (Automatic Gain Control), an automatic control method that automatically adjusts the gain of the amplifier circuit with the strength of the input signal. There are two control methods for AGC: one is to reduce the gain by increasing the AGC control voltage, which is called forward AGC, and the other is to reduce the gain by reducing the AGC control voltage, which is called reverse AGC. [0003] The AD undersampling technique is a technique that uses undersampling criteria in ADC applications. According to the Nyquist theory: the sampling rate (fs) must be greater than twice the highest frequency component (fa) of the signal in order to achieve a more accurate sampling effect. The frequency of signals in the modern communica...

AI Technical Summary

Problems solved by technology

[0009] Nowadays, the commonly used high-speed data acquisition cards are generally PCI cards, ISA cards and USB cards. Restrictions, poor scalability; in some test sites with strong electromagnetic interference, it is impossible to specifically shield them, resulting in distortion of the collected data

[0010] Most of the early data acquisition cards were designed based on CPLD. In this case, the data sampling speed and sampling accuracy are not high. Due to the influence of CPLD resources, it is impossible to perform complex processing on the sampling data, and can only rely on the back-end equipment for storage. After processing, its real-time performance is low

[0011] In radar, communication and other fields, a complete communication link must have signal reception and transmission. Generally, general-purpose acquisition cards only have the function of data sampling, and cannot rely on a single board to send the processed data to the outside.

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