Reducing collisions in a radio communications system

• US 6,888,882 B1
• Filed: 11/30/2000
• Issued: 05/03/2005
• Est. Priority Date: 11/30/2000
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: ArrayComm LLC (Ygomi LLC)
• Inventors: Dogan, Mihat C.
• Primary Examiner(s): Chin, Stephen
• Assistant Examiner(s): Pathak, Sudhanshu C.
• Application Number:
  US09/726,375
• Time in Patent Office: 1,615 Days
• Field of Search: 375/220, 375/343, 375/130, 375/147, 375/294, 375/132, 375/365, 375/140, 375/150, 375/136, 375/135, 370/280, 370/334, 370/342, 370/335, 370/350, 370/347, 370/337, 463/20
• US Class Current: 375/220
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0865 Independent weighting, i.e. weights based on own antenna reception parameters
• CPC Class Codes: H04B 7/2678 Time synchronisation
• CPC Class Codes: H04W 56/0035 detecting errors in frequency or phase
• CPC Class Codes: H04W 56/0085 detecting a given structure in the signal

Abstract

A method and apparatus are provided that allows a predetermined training sequence to be selected from among different choices. According to one aspect of the present invention, the invention includes receiving a downlink broadcast burst from a base station, determining timing for sending an uplink burst, selecting a training sequence for the uplink burst; and transmitting the uplink burst using the selected training sequence.

Claims

1. A method comprising:

receiving at a receiving station a downlink broadcast burst from a base station;

determining timing for transmitting an uplink burst;

selecting a training sequence at the receiving station for the uplink burst by determining a digit from a number stored in the receiving station, the number being unique to each receiving station, and applying the determined digit to select from among a set of predetermined training sequences; and

transmitting the uplink burst from the receiving station using the selected training sequence.

2. The method of claim 1 wherein the stored number comprises the identification number of the receiving station.

3. The method of claim 1 wherein receiving a downlink broadcast burst comprises receiving an indication of a set predetermined training sequences for use in selecting a training sequence.

4. The method of claim 1 wherein determining timing comprises determining timing of a broadcast channel on which broadcast burst was received.

5. The method of claim 1 wherein determining timing comprises determining nominal timing relative to a frame of the broadcast burst.

6. The method of claim 1 wherein determining timing comprises determining timing on a broadcast channel on which the broadcast burst was received.

7. The training sequence of claim 1 wherein the training sequence training sequence comprises a repetition of a core sequence successively a specified number of times.

8. The training sequence of claim 7 wherein the core sequence has 12 symbols.

9. The training sequence of claim 7 wherein the core sequence has a normalized cross-correlation of about ⅓

.

10. The training sequence of claim 7 wherein the core sequence has a normalized autocorrelation of about ⅓

.

11. The training sequence of claim 7 wherein the absolute value of the mean of the core sequence is about zero.

12. A machine-readable medium having stored thereon data representing sequences of instructions which, when executed by a machine, cause the machine to perform operations comprising:

receiving at a receiving station a downlink broadcast burst from a base station;

determining timing for transmitting an uplink burst;

selectin a training sequence at the receiving station for the uplink burst by determining a digit from a number stored in the receiving station, the number being unique to each receiving station, and applying the determined digit to select from among a set of predetermined training sequences; and

transmitting the uplink burst from the receiving station using the selected training sequence.

13. The medium of claim 12 wherein the stored number comprises a sequence further comprising instructions for determining a digit from an identification number of the receiving station.

14. The medium of claim 12 wherein the instructions causing the machine to perform operations comprising receiving a downlink broadcast burst further comprise instructions for receiving an indication of a set of predetermined training sequences for use in selecting a training sequence.

15. An apparatus comprising:

a receiver to receive a downlink broadcast burst from a base station;

a processor to determine timing for sending an uplink burst, and to selecting a training sequence at the receiving station for the uplink burst by determining a digit from a number stored in the receiving station, the number being unique to each receiving station, and applying the determined digit to select from among a set of predetermined training sequences for the uplink burst; and

a transmitter to transmit the uplink burst using the selected training sequence.

16. The apparatus of claim 15 further comprising a register containing an identification number of the apparatus and wherein the processor selects by determining a digit from the identification number register.

17. The apparatus of claim 15 wherein the receiver receives a downlink broadcast burst including an indication of a set of predetermined training sequences for use in selecting a training sequence.

18. The method of claim 15 wherein determining timing comprises determining timing of a broadcast channel on which the broadcast burst was received.