Apparatus for high-speed demodulation under bandwidth-constrained conditions

Abstract

The invention discloses a device for high-speed demodulation under the condition of limited bandwidth, including a test source unit, a demodulation intermediate frequency unit, an AD conversion unit, a demodulation synchronization unit, a non-ideal channel compensation unit, a decoding unit, and a self-test unit. The device relates to pseudo-random sequence technology, orthogonal modulation technology, channel simulation technology, AD conversion technology, clock recovery technology, carrier recovery technology, non-ideal channel compensation technology and LDPC coding and decoding technology in the communication field. The test source unit generates the modulated signal; the demodulation intermediate frequency unit completes the level adjustment and quadrature demodulation of the input signal; the AD conversion unit completes the analog-to-digital conversion of the demodulated signal; the demodulation synchronization unit completes clock and carrier synchronization; non-ideal channel compensation The unit completes the correction of channel distortion; the decoding unit completes LDPC high-speed decoding; the self-test unit performs bit error comparison. Compared with the traditional high-speed demodulation technology, the invention has the ability to compensate channel distortion, can simulate various transmission systems, can perform self-loop testing, has the advantages of strong adaptability and simple operation.

Description

technical field [0001] The invention relates to a device for high-speed demodulation under the condition of limited bandwidth in the communication field, and is especially suitable for high-speed demodulation module of satellite-ground high-speed data transmission and high-speed receiving terminal in broadband communication under the condition of limited bandwidth channel. Background technique [0002] In satellite-to-ground high-speed data transmission and broadband communication systems with limited bandwidth, high-order modulation systems should be selected for transmission as much as possible to achieve the purpose of saving bandwidth and increasing transmission rates. However, the high-order modulation system is very sensitive to the nonlinear distortion of the power amplifier and will introduce nonlinear distortion. In the previous system, there is no non-ideal channel compensation function, and the nonlinear distortion can only be solved by power back-off, but this wi...

AI Technical Summary

Problems solved by technology

However, the high-order modulation system is very sensitive to the nonlinear distortion of the power amplifier and will introduce nonlinear distortion

In the previous system, there is no non-ideal channel compensation function, and only power backoff can be used to solve nonlinear distortion, but this will cause power waste

In the previous system, there is no complex channel simulation function, no channel distortion compensation function, different encoding and decoding parameters, different modulation systems, and bit error rate indicators under different channel conditions cannot be tested, making high-speed demodulation technology The scope of application of the project is greatly reduced

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