Method for unifying secondary synchronization signal detection and frame timing synchronization

An apparatus for joint secondary synchronization signal detection and frame timing synchronization, comprising:

• a local secondary synchronization sequence generation module, which is configured to:
• generate two local secondary synchronization sequences, i.e. SSC1—n and SSC2—n, according to a sector number of a cell group, and send the local secondary synchronization sequences SSC1—n and SSC2—n to a multiple-frame average module, wherein n is an index of multiple-frame average, and n=0;
• the multiple-frame average module, which is configured to:
• convert received one frame time domain signal to frequency domain to obtain secondary synchronization signals S1 and S2 to be detected respectively corresponding to two half-frames of the one frame time domain signal;
• carry out inner products on said S1 and S2 with SSC1—n and SSC2—n respectively to obtain [S1,SSC1—n], [S2,SSC2—n], [S1,SSC2—n], [S2,SSC1—n], then combine inner product results to obtain sets [S1,SSC1—n]+[S2,SSC2—n] and [S1,SSC2—n]+[S2,SSC1—n], let P1—n=P1—n−1+[S1,SSC1—n]+[S2,SSC2—n], P2—n=P2—n−1+[S1,SSC2—n]+[S2,SSC1—n], and send the P1—n and P2—n to a frame timing synchronization module, wherein P1—−1 and P2—−1 are empty sets;
• the frame timing synchronization module, which is configured to:
• select a maximum value P of absolute values of correlation values in the P1—n and P2—n, and judge whether the maximum value P is greater than a preset threshold Tmax, and if yes, take the index of the maximum value P as an ID number of the cell group, and complete one frame timing synchronization by judging whether the maximum value occurs in P1—n or P2—n;
• if not, compare the absolute values of the correlation values in the P1—n and P2—n with a threshold Tccv, select the secondary synchronization sequences corresponding to the correlation value of which the absolute value is not less than the Tccv in the P1—n and P2—n as new secondary synchronization sequences SSC1—n and SSC2—n with the index being increased by 1 to send to the multiple-frame average module.