Demodulation method of independent sideband modulation signal based on fpga

Abstract

The invention discloses an independent sideband modulation signal demodulation method based on an FPGA, and the method comprises the steps: building a mathematical expression formula of an independentsideband modulation signal s(t); carrying out the Hilbert transformation of the signal s(t), and obtaining a signal s(t)<^>; inputting the signals s(t) and s(t)<^> into a first channel, and carryingout the down-conversion operation; enabling the signals to pass through a group of extraction filters, and obtaining a signal m1(t); inputting the signals s(t)<^> and s(t) into a second channel, carrying out the down-conversion calculation, enabling the signals to pass through a group of extraction filters, and obtaining a signal m2(t); carrying out the Hilbert transformation of the signal m2(t),and obtaining a signal m2(t)<^>; carrying out the Hilbert transformation of the signal m2(t)<^> again, and obtaining a signal -m2(t); carrying out the algorithm calculation of the obtained signals m1(t) and m2(t)<^>, and respectively solving upper and lower sideband signals. Based on the software radio core thought, the method employs the basic idea of the digital quadrature demodulation, combinesthe Hilbert transformation, designs two paths, achieves the algorithm calculation of the obtained signals, obtains the upper and lower sideband signals, is high in sensitivity of a demodulated signal, and is suitable for the demodulation application of LSB / USB / SSB signals.

Description

technical field [0001] The invention belongs to the field of radio monitoring, and in particular relates to an FPGA-based independent sideband modulation signal demodulation method, which can be used for the demodulation application of receivers to ISB signals. Background technique [0002] In wireless communication transmission, it is roughly divided into a signal transmitting module and a signal receiving module. The signal transmitting module converts the baseband signal that needs to be transmitted into a functional module suitable for transmission in the channel. Since it includes lower frequency components, it needs to be processed. Modulation processing moves the frequency to a higher frequency to improve transmission efficiency; and the signal receiving module is its inverse process, which demodulates the modulated signal to obtain the required baseband signal. The ISB signal is a new type of signal modulation. The two sideband signals of the modulated signal can be ...

AI Technical Summary

Problems solved by technology

[0010] The purpose of the present invention is to overcome the strong demand of existing baseband sideband filter method to data processing capability and high computing speed, the shortcoming that is not easy to realize in FPGA, proposes a kind of novel ISB demodulation method based on FPGA realization

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