Method and apparatus using cell-specific and common pilot subcarriers in multi-carrier, multi-cell wireless communication networks

摘要

A multi-carrier cellular wireless network (400) employs base stations (404) that transmit two different groups of pilot subcarriers: (1) cell-specific pilot subcarriers, which are used by a receiver to extract information unique to each individual cell (402), and (2) common pilots subcarriers, which are designed to possess a set of characteristics common to all the base stations (404) of the system. The design criteria and transmission formats of the cell-specific and common pilot subcarriers are specified to enable a receiver to perform different system functions. The methods and processes can be extended to other systems, such as those with multiple antennas in an individual sector and those where some subcarriers bear common network/system information.

主权项

1. A transmitting method for a base station in a cell within a group of cells in an orthogonal frequency division multiplexing system, the base station having multiple transmission branches, the method comprising:
transmitting cell-specific pilot subcarriers, in accordance with a transmission diversity scheme or a multiple-input multiple-output scheme, wherein the cell-specific pilot subcarriers possess amplitudes, phases, and frequency subcarrier indices specific to the cell; and some of the cell-specific pilot subcarriers are not aligned in frequency subcarrier index with cell-specific pilot subcarriers transmitted by another base station in the group of cells; transmitting common pilot subcarriers in accordance with a common pilot transmission scheme, wherein: the common pilot subcarriers are aligned in frequency subcarrier index with common pilot subcarriers transmitted by other base stations in the group of cells; a ratio of an amplitude (ai,m and an,m) of two common pilot subcarriers having a same time index (tk) that are transmitted via a common transmission branch is a constant for the group of cells; and a difference of a phase (φi,m and φn,m) of two common pilot subcarriers having a same time index (tk) that are transmitted via a common transmission branch is a constant for the group of cells; and controlling independently a transmission power of the cell-specific pilot subcarriers and a transmission power of the common pilot subcarriers.