CODE DIVISION MULTIPLE ACCESS TRANSMISSION ANTENNA WEIGHTING

• US 20110026496A1
• Filed: 10/11/2010
• Published: 02/03/2011
• Est. Priority Date: 09/10/1999
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Mesecher, David K.
• Granted Patent: US 9,219,522 B2
• Time in Patent Office: Days
• US Class Current: 370/335
• CPC Class Codes: H04B 1/712 Weighting of fingers for combining, e.g. amplitude control or phase rotation using an inner loop
• CPC Class Codes: H04B 2201/70701 featuring pilot assisted reception
• CPC Class Codes: H04B 7/0613 using simultaneous transmission H04B7/0686 takes precedence
• CPC Class Codes: H04B 7/0615 of weighted versions of same signal
• CPC Class Codes: H04B 7/0619 using feedback from receiving side feedback signaling for adaptive modulation/coding H04L1/0001
• CPC Class Codes: H04B 7/0634 Antenna weights or vector/matrix coefficients
• CPC Class Codes: H04B 7/0678 using different spreading codes between antennas code allocation H04J13/16
• CPC Class Codes: H04B 7/0845 per branch equalization, e.g. by an FIR-filter or RAKE receiver per antenna branch rake receivers as such H04B1/7115
• CPC Class Codes: H04B 7/0854 using error minimizing algorithms, e.g. minimum mean squared error [MMSE], "cross-correlation" or matrix inversion
• CPC Class Codes: H04B 7/0857 using maximum ratio combining techniques, e.g. signal-to- interference ratio [SIR], received signal strenght indication [RSS]
• CPC Class Codes: H04B 7/0891 Space-time diversity rake receivers H04B1/7115; space-time decoding H04L1/0631
• CPC Class Codes: H04J 13/0003 Code application, i.e. aspects relating to how codes are applied to form multiplexed channels

Abstract

A code division multiple access communication system has a base station with a plurality of transmitting antennas. From each transmitting antenna of the base station, a pilot signal is transmitted having a different chip sequence than the other transmitting antenna. At a user equipment, the transmitted pilot signals are received from each transmitting antenna. A weight adjustment is derived in response to the received transmitted pilot signals. The user equipment transmits the weight adjustment to the base station. The transmitted weight adjustment is received from the user equipment. A data signal is processed to produce a plurality of versions of the data signal. At least a portion of each processed data signal has a different chip sequence than the other processed data signal version. At least one processed data signal version is weighted by a weight value adjusted in response to the received transmitted weight adjustment. From each transmitting antenna, a different one of the data signal versions is transmitted and the transmitted data signal versions are received at the user equipment.

Claims

1. A user equipment (UE) comprising:

circuitry configured to receive signal(s) transmitted by plurality of antennas of a base station;

wherein the received signal having from each transmitting antenna a sequence of symbols unique to that antenna and the received signal having a weighted sequence of symbols transmitted from all of the plurality of antennas;

wherein the circuitry is further configured to derive a preferred weight for a subsequent received signal based on the received signal and transmit an indication of the preferred weight to the base station.

2. The UE of claim 1, wherein the sequences of symbols from each antenna and the weighted sequence of symbols are derived from a same type of sequence.

3. The UE of claim 2, wherein the same type of sequence is a pseudo random sequence.

4. The UE of claim 2, wherein the sequences of symbols from each antenna are pilot symbols.

5. A base station comprising:

a plurality of antennas that transmit signal(s), wherein each signal comprises a sequence of symbols unique to each one of the plurality of antennas and the signal has a weighted sequence of symbols,

wherein the antenna is configured to receive a signal indicating a preferred weight for a subsequent transmission signal based on the preferred weight.

6. The base station of claim 5, wherein the sequences of symbols and the weighted sequence of symbols are derived from a same type of sequence.

7. The base station of claim 6, wherein the same type of sequence is a pseudo random sequence.

8. The base station of claim 6, wherein the sequences of symbols are pilot symbols.

9. A method for deriving a preferred weight for a received signal from a Node B based on a received signal and transmitting an indication of the preferred weight to the base station comprising:

receiving signal(s) transmitted by plurality of antennas of a base station wherein the received signal has from each transmitting antenna a sequence of symbols unique to that antenna and the received signal has a weighted sequence of symbols transmitted from all of the plurality of antennas;

deriving a preferred weight for a subsequent received signal based on the received signal; and

transmitting an indication of the preferred weight to the base station.

10. The method of claim 9, wherein the sequences of symbols and the weighted sequence of symbols are derived from a same type of sequence.

11. The method of claim 10, wherein the same type of sequence is a pseudo random sequence.

12. The method of claim 10, wherein the sequences of symbols are pilot symbols.