Cell search procedure for heterogeneous networks

摘要

In a heterogeneous network, low power cells are detected by correlating a first and second signal originating from an unknown cell, such as synchronization signals, e.g., SSS received in a first and second time period (e.g., subframes 0 and 5 of a frame with corresponding sets of possible SSS signals. The cell identities for the candidate cells can be used to determine corresponding reference symbol sequences for the candidate cells. The final determination of the cell identity is then made by correlating a third signal originating from the unknown cell, such as a reference signal received in a third time period (e.g., an almost blank subframe or a broadcast subframe) with the set of reference signals for the candidate cells. The correct cell identity is determined to be the cell identity yielding the greatest correlation with its corresponding reference signal.

主权项

1. A method of determining the cell identity of a cell in a wireless network, said method comprising:
correlating a first signal originating from an unknown cell in a first time period with a first set of possible synchronization signals to obtain a first set of correlations; correlating a second signal originating from the unknown cell in a second time period with a second set of possible synchronization signals to obtain a second set of correlations; selecting a candidate set of cell identities for the unknown cell based on the first and second sets of correlations; correlating a third signal originating from the unknown cell in a third time period with a set of reference signals corresponding to the cell identities in the candidate set to obtain a third set of correlations; and selecting a cell identity associated with a reference signal in said third set having the greatest correlation with the third signal.