Pilot design using costas arrays

摘要

A multi-pilot frame handler (36) of a radio access network node (28) is arranged to prepare a block of a frame of information to include a first pilot signal of a pilot signal first type and a first pilot signal of a pilot signal second type. The pilot signal of the pilot signal first type is expressed as a first Costas array base pattern of resource elements of the block; the pilot signal of the second type is expressed as a second Costas array base pattern of resource elements of the block. The multi-pilot frame handler (36) is arranged to prepare the block so that any pilot signal of the pilot signal first type is carried by at least some subcarriers of a first set of subcarriers of the block and any pilot signal of the pilot signal second type is carried by at least some subcarriers of a second set of subcarriers of the block.

主权项

1. A method of operating a node of a radio access network, the method comprising:
the node providing a frame of information comprising at least one block, the block comprising frequency-time resources structured in a frequency-time plane array, the frequency-time plane array comprising plural frequency subcarriers and plural symbols; selecting at the node a first set of frequency-time resources of the block for carrying any pilot signals which serve as a pilot signal of a pilot signal first type; selecting at the node a second set of frequency-time resources of the block for carrying any pilot signals which serve as a pilot signal of a pilot signal second type; the second set being mutually exclusive relative to the first set; using at the node a first base pattern of frequency-time resources of the block derived from a first Costas array for forming a first pilot signal of the pilot signal first type and allocating the frequency-time resources of the block whereby the first pilot signal of the pilot signal first type is carried by at least some frequency-time resources of the first set of frequency-time resources; using at the node a second base pattern of frequency-time resources of the block derived from a second Costas array for forming a first pilot signal of the pilot signal second type and allocating the frequency-time resources of the block whereby the first pilot signal of the pilot signal second type is carried by at least some frequency-time resources of the second set of frequency-time resources, the second base pattern being different from the first base pattern and the second Costas array being different from the first Costas array; wherein for a shift of an integer number M subcarriers in frequency and an integer number N symbols in time, shifting a symbol at index (i,j) in the first base pattern derived from the first Costas array to an index (mod(i+N, A), mod(j+M,B) to form a second pilot signal of the pilot signal first type, where A is an integer number of symbols in the block and B is an integer number of subcarriers in the block; the node transmitting the frame including the block over a radio interface.