A Parallel Frequency Point Flexible and Adjustable Σ-δ Modulator and Its Working Method

Abstract

The invention discloses a parallel Sigma-Delta modulator with flexible and adjustable frequency points and a working method thereof. The tunable frequency band range of the Sigma-Delta modulator is 0-fs / 2. The frequency points are flexibly switched and highly universal. The Sigma-Delta modulator is suitable for power amplifiers in 0-s / 2 different working frequencies. Based on the simplicity and modularization of the basic model of the Sigma-Delta modulator, the structure of the Sigma-Delta modulator can be conveniently expanded, so a equivalent time interlacing bandpass Sigma-Delta modulator of a bi-branch, tri-branch, quadric-branch or more branches is obtained, and is converted into a parallel bandpass Sigma-Delta modulator based on key node signal operation, which is highly expandable.Thus, logic operation time delays are reduced; the maximum working frequency of the Sigma-Delta modulator in the circuit is improved, sampling frequency of the modulator is improved and the signal tonoise ratio of the output signal of the modulator is improved.

Description

technical field [0001] The present invention relates to the technical field of sigma-delta modulators with flexible and adjustable parallel frequency points in digital transmitters, in particular to a tunable frequency point, capable of working at high sampling frequency, strong reconfigurability, good flexibility and A sigma-delta modulator for switching power amplifiers and its working method. Background technique [0002] In the development process of wireless communication systems, due to the different requirements of application scenarios, communication systems need to be able to process signals in different frequency bands, rates, and standard standards for different encoding and modulation, which also makes traditional analog front-ends appear. With the trend of digitalization, concepts such as software-defined radio and digital transceivers have emerged. The digital transmitter based on the digital circuit completes the baseband signal processing and up-conversion p...

AI Technical Summary

Problems solved by technology

The main problem in the above-mentioned digital transmitter system is: because the operating clock frequency of the digital circuit is very limited, generally 200MHz to 500MHz for the FPGA, the sampling frequency of the traditional Σ-Δ modulator must be less than or equal to the circuit's The highest clock frequency, which limits the generation of high signal-to-noise ratio signals

In addition, traditional Σ-Δ modulators are generally low-pass Σ-Δ modulators or band-pass Σ-Δ modulators with fixed frequency points, which is not easy to achieve a common frequency point tunable, multi-rate, multi-standard system coexistence , flexible and efficient reconfigurable digital transmitter

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