Method for implementing hard switching between access networks

Abstract

The invention discloses a method for realizing hard handoff between access networks. The method comprises the following steps: S302, a source side access network transmits a calculated loop round-trip delay time of a pilot frequency of a target side access network or the calculated loop round-trip delay time of the pilot frequency of the source side access network to the target side access network while needing the hard handoff between the access networks; and S304, the target side access network sets a search window center of the pilot frequency of the target side access network according tothe loop round-trip delay time of the pilot frequency of the target side access network, or computes the loop round-trip delay time of the pilot frequency of the target side access network according to the loop round-trip delay time of the pilot frequency of the source side access network and sets the search window center of the pilot frequency of the target side access network according to the loop round-trip delay time of the pilot frequency of the target side access network to realize the hard handoff between the source side access network and the target side access network. The method canhelp realize the hard handoff between the access networks smoothly.

Description

technical field [0001] The present invention relates to the communication field, and more specifically relates to a method for realizing hard handover between access networks. Background technique [0002] There are three system times in the Code Division Multiple Access (CDMA) system, namely, the base station transmitting system time, the access terminal (AccessTerminal, referred to as AT) receiving system time (the AT transmitting system time coincides with it), and the base station Receive system time. The three vertical thick lines shown in Figure 1 represent the above-mentioned system time respectively. The AT receiving system time is delayed relative to the base station transmitting system time, and the base station receiving system time is delayed relative to the AT receiving system time. [0003] In the following, it is assumed that a signal of a base transceiver station (Base Transceiver Station, BTS for short) can propagate to the AT in a straight line, and other...

AI Technical Summary

Problems solved by technology

However, because the target AN cannot receive the RU message, it cannot obtain the RTD of the PN of the target side AN.

In this way, the CE of the AN on the target side cannot determine its own search window center

This will cause the CE of the target AN to capture the reverse pilot channel of the AT when the AT is handed over to the cell of the target AN.

Images