US 7,738,437 B2 · Physical layer structures and initial access schemes in an unsynchronized communication network

Abstract

Physical layer structures and related access schemes for unsynchronized communication networks are provided. Access channel information, preferably including a common synchronization code associated with all transceiver stations in a communication network and a cell-specific synchronization code uniquely associated with one of the transceiver stations, is modulated onto at least one set of time-continuous signal components of a communication signal. In order to access the communication network, communication terminals search for the access channel information in one or more sets of time-continuous signal components and synchronization parameters are then determined based on a location of the access channel information in the sets of time-continuous signal components. Some embodiments of the invention provide for joint frame synchronization and coarse timing synchronization. In further embodiments, the communication signal also includes a scattered pilot channel onto which a portion of the access channel information, preferably the cell-specific synchronization code, is modulated. The pilot channels may then be re-used for initial access operations in addition to its conventional uses for such operations as channel estimation.

Claims15

Dependent claims

A method of transmitting information in an unsynchronized Orthogonal Frequency Division Multiplexing (OFDM) communication network comprising a plurality of base stations, the method comprising:

modulating access channel information onto a predetermined initial access channel of an OFDM communications signal, wherein the access channel information comprises a common synchronization code that is common to each of the plurality of base stations and a cell-specific synchronization code that is orthogonal to the common synchronization code and unique to each base station, and wherein the initial access channel comprises a predetermined set of one or more time-continuous signal components of the OFDM communications signal, each time-continuous signal component being carried by a respective sub-carrier;
and transmitting the communication signal.

A method of transmitting information in an unsynchronized Orthogonal Frequency Division Multiplexing (OFDM) communication network comprising a plurality of base transceiver stations, the method comprising:

modulating a cell-specific synchronization code uniquely associated with a selected one of the plurality of base transceiver stations onto a scattered pilot channel of an OFDM communication signal;
modulating access channel information to a predetermined initial access channel of the OFDM communications signal, wherein the access channel information comprises the cell-specific synchronization code and a common synchronization code that is orthogonal to the cell-specific synchronization code and common to each of the plurality of base transceiver stations, and wherein the initial access channel comprises a predetermined set of one or more time-continuous signal components of the OFDM communications signal, each time-continuous signal component being carried by a respective sub-carrier;
and
transmitting the communication signal.

1 more element

Dependencies are inferred from the claim text.

Physical layer structures and initial access schemes in an unsynchronized communication network

Life of this patent

Physical layer structures and initial access schemes in an unsynchronized communication network

Life of this patent

Abstract

Claims15