Frequency offset processing method and device for multi-mode terminal

Abstract

The invention provides a frequency offset processing method and a frequency offset processing device for a multi-mode terminal. The multi-mode terminal generates a reference clock through a digital compensation crystal oscillator (DCXO) and at least supports communication with a first communication network and a time division-synchronization code division multiple access (TD-SCDMA) network. The method comprises the following steps that: the multi-mode terminal resides in the first communication network to detect that TD-SCDMA service is needed to be performed; the multi-mode terminal reads cell broadcast information in the TD-SCDMA network and performs frequency offset estimation by utilizing P-channel common control physical channel (P-CCPCH) of a time slot 0 to obtain a frequency offset estimation value; and the multi-mode terminal performs frequency offset compensation on the P-CCPCH data according to the frequency offset estimation value. The performance of various services of a TD-SCDMA system can be guaranteed when the multi-mode terminal resides in different systems.

Description

A frequency offset processing method and device for a multi-mode terminal technical field The invention belongs to the field of mobile communication, in particular to a frequency offset processing method and device for a multi-mode terminal using a digitally compensated crystal oscillator (DCXO). Background technique At present, in the clock interface circuit of the terminal, a transceiver including a voltage-controlled crystal oscillator (VCXO) or a fully digitally controlled crystal oscillator is commonly used. The VCXO itself has a temperature compensation circuit that can automatically compensate for frequency offsets caused by temperature changes. . Due to the lower cost and smaller size of the digitally compensated crystal oscillator (DCXO), the DCXO has gradually been adopted in the terminal to generate the system reference clock. However, the DCXO itself does not have the function of automatically adjusting the frequency according to the temperature change. There...

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Problems solved by technology

However, the DCXO itself does not have the function of automatically adjusting the frequency according to the temperature change. Therefore, when the terminal performs different services, it should consider the frequency offset problem caused by the temperature change.

Especially, for a multi-mode terminal, when the multi-mode terminal resides in a different system (a system different from TD-SCDMA) and needs to perform TD-SCDMA services, if the frequency offset is not compensated and / or adjusted in time, the Affects the performance of various services in the TD-SCDMA system, and the prior art does not provide a solution for how to deal with frequency offset in this situation

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