Frame structure of time division duplex system and method for sending synchronous signals

Abstract

The invention provides a frame structure of a time division duplex system and a method for sending synchronous signals. The method comprises that: a base station sends a main synchronous signal and an auxiliary synchronous signal on last two orthogonal frequency division multiplexing signals of a same downlink time slot of each half frame respectively, and the time slot is different from the time slot for sending the main synchronous signal and the auxiliary synchronous signal in a frequency division duplex system; and the base station also sends a main physical broadcast channel of system broadcast information on continuous multiple orthogonal frequency division multiplexing signals of a downlink time slot of any half frame of the half frame, and the time slot of the main physical broadcast channel for sending the system broadcast information is on a same subframe as the time slot for sending the main synchronous signal and the auxiliary synchronous signal in the half frame. By using the frame structure and the method, under the condition that a double-mode terminal detects out a duplex mode in advance, the search performance of a cell can be improved; and according to the size of a time domain interval from the synchronous signals to the physical broadcast channel, the method can easily help the double-mode terminal to detect the duplex mode.

Description

technical field [0001] The invention relates to the field of mobile communication, in particular to a method for sending synchronous signals of a time division duplex system. Background technique [0002] The frame structure of the current third-generation mobile communication time-division duplex (Time Divided Duplex, TDD) long-term evolution system (Long-Term Evolution, LTE), such as figure 1 shown. In this frame structure, a 10ms radio frame is divided into two half frames, each half frame is divided into 10 time slots with a length of 0.5ms, and every two time slots form a subframe with a length of 1ms, and a radio frame A radio frame contains 10 subframes (numbered from 0 to 9), and a radio frame contains 20 time slots (numbered from 0 to 19). For the conventional cyclic prefix (Cyclic Prefix, CP) with a length of 5.21us and 4.69us, a time slot contains 7 uplink / downlink symbols with a length of 66.7us, of which the length of the first symbol cyclic prefix is ​​5.21us...

AI Technical Summary

Problems solved by technology

Therefore, compared to the LTE FDD system, the cell search performance of LTE TDD is low

In addition, the transmission of the primary synchronization signal on the third OFDM symbol of the DwPTS will also affect the design of the downlink control signaling of the LTE TDD system. The LTE system stipulates that the control signaling can be on the first 1, 2 or 3 OFDM symbols of the downlink subframe. However, for DwPTS, the protocol has to stipulate that the downlink control signaling should be sent on the first 1 or 2 OFDM symbols to avoid conflict with the main synchronization channel, which may cause a mismatch in the downlink coverage capability and increase the complexity of sending control signaling Spend

Images