Method and apparatus for generating a carrier frequency signal

Abstract

A method and apparatus for generating a carrier frequency signal is disclosed. The method includes generating a first frequency signal; injecting a modulation signal at a first point of the two-point modulation architecture; 5 generating a second frequency signal from the modulation signal; introducing the second frequency signal by mixing the first frequency signal and the second frequency signal to generate a mixed frequency signal and outputting the carrier frequency signal selected from the mixed frequency signal.

Description

technical field

[0001] The present invention relates to the communication field, in particular to a method and equipment for generating carrier frequency signals. Background technique

[0002] Using the polar modulation structure, the phase modulation of the carrier is performed by a method of modulating a phase locked loop (Phase Locked Loop, PLL) in a frequency synthesizer used to generate the carrier. In order to minimize the noise from the PLL, its loop filter (loop filter, LPF) bandwidth is usually relatively small. The modulation bandwidth of modern wireless communication protocols (such as Wideband Code Division Multiple Access (WCDMA), Enhanced Data Rates for GSM Evolution (EDGE), and others) is usually larger than this bandwidth. Furthermore, the bandwidth required for phase modulation is approximately five times the modulation bandwidth. This creates a problem: when modulating the PLL directly, it limits the modulation bandwidth because it applies a low-pass filt...

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