Trim for dual-port frequency modulation

Abstract

The application relates to trim for dual-port frequency modulation. Various methods provide for trimming the gain in a dual-port phase-locked loop (PLL) of a radio transceiver. Use is made of the radio's demodulator to perform modulation accuracy measurements, thereby reducing the cost and complexity of external test equipment.

Description

[0001] This application claims the benefit of Provisional Patent Application No. 62 / 187,667, filed July 1, 2015, the contents of which are hereby incorporated by reference in their entirety. technical field [0002] This application is concerned with pruning for two-port frequency modulation. Background technique [0003] In order to obtain the ideal all-pass modulation characteristic of the phase-locked loop (PLL) of the radio transceiver (in the ideal all-pass modulation characteristic, the switching functions of the two ports of the PLL are complementary), the two ports of the PLL are modulated simultaneously, And the overall transfer function seen by the modulating signal will preferably have an all-pass characteristic. However, to achieve the ideal all-pass characteristic, the two ports of the PLL must have equal gains. While digital gain is stable and accurate, analog gain can vary with processing and temperature, so must be trimmed at the factory just like digital ga...

AI Technical Summary

Problems solved by technology

The need for an external receiver adds complexity and cost to the pruning station

Images