Switchable equalizer for demodulator

Abstract

The invention relates to a convertible equalizer used for a demodulator. The convertible balancer comprises a forward direction equalizer set, a backward direction equalizer set, a special equalizer set, a first controller, a second controller, a judging device, an error calculator and an accumulator. The special equalizer set can be controlled by the first controller and the second controller to switch between a forward direction working mode and a backward direction working mode. The input end of the forward direction equalizer is connected with the input end of the convertible equalizer. Output signals of the judging device can be used as output signals of the convertible equalizer. By the adoption of the structure, the convertible equalizer used for the demodulator can reduce the order of the front direction equalizer set and the order of the backward direction equalizer set, greatly improves the dynamic channel processing ability of the demodulator, is simple in structure, quick in dynamic tracking, little in free noise, and quick in rate of convergence, is reduced in cost, and has a wider application range.

Description

technical field [0001] The invention relates to the field of communication signal processing, in particular to the field of equalizers, in particular to a switchable equalizer for a demodulator. Background technique [0002] In the field of modern digital communication, adaptive equalizers are widely used in digital cable TV signal demodulators. The main function of adaptive equalizers is to offset the interference of multipath reflections, reduce noise and improve the performance of demodulators. At the same time, such an adaptive equalizer can also be used in a wireless digital communication system. Equalizers are often used for signal recovery in digital TV / audio broadcast receivers such as the US, Europe and China. [0003] Since multipath and channel fading are the most common problems encountered in real digital communication systems, adaptive equalizers are generally more effective methods for solving multipath and channel fading problems. Described and detailed in ...

AI Technical Summary

Problems solved by technology

[0013] However, this patent has obvious disadvantages in the actual implementation process: additional circuits and time are required to determine the position of the "non-zero coefficient", and the arithmetic unit needs to slide to the corresponding position. If the position of the "non-zero coefficient" Time changes, because the channel fading changes with time, which is a common phenomenon in the actual environment, then the performance of the equalizer using this patent will be unstable

However, it still does not solve the problem of reducing the equalizer order under the premise of ensuring system performance.

Images