Method and apparatus for accessing a wireless multi-carrier communication system

• US 20050286547A1
• Filed: 12/03/2004
• Published: 12/29/2005
• Est. Priority Date: 06/24/2004
• Status: Abandoned Application

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Inventors: Baum, Kevin L., Nangia, Vijay
• Application Number:
  US11/004,358
• Publication Number:
  US 20050286547A1
• Time in Patent Office: Days
• US Class Current: 370/437
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04J 3/0682 by delay compensation, e.g. by compensation of propagation delay or variations thereof, by ranging
• CPC Class Codes: H04L 5/023 Multiplexing of multicarrier modulation signals multicarrier modulation H04L27/2601
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access

Abstract

A subscriber station (101-103) accesses a multicarrier communication system (100) by determining (505) one or more channel characteristics that is indicative of a range of the subscriber station from a base station, selecting (510) an access code that generates an access signal having a peak to average power ratio, using the one or more channel characteristics, generating (515) an access signal from the access code, and transmitting (525) the access signal and also by determining (405) one or more channel characteristics of each frequency sub-band of a set of frequency sub-bands, selecting (410) a frequency sub-band of the set of frequency sub-bands based on the one or more channel characteristics, and transmitting (420) the access signal on the selected frequency sub-band.

Claims

1. A method used by a subscriber station for accessing a wireless multi-carrier communication system, comprising:

determining one or more channel characteristics of each frequency sub-band of a set of frequency sub-bands;

selecting a frequency sub-band of the set of frequency sub-bands based on the one or more channel characteristics;

forming an access signal; and

transmitting the access signal on the selected frequency sub-band.

2. The method according to claim 1, further comprising:

determining a rate of change of the one or more channel characteristics;

selecting a frequency sub-band of the set of frequency sub-bands randomly when the rate of change of the one or more channel characteristics is greater than a threshold.

3. The method according to claim 1, futher comprising:

determining one or more channel characteristics of a set of frequency sub-bands that is indicative of a range of the subscriber station from a base station;

selecting an access code that generates an access signal having a peak to average power ratio, using the one or more channel characteristics; and

generating the access signal from the access code.

4. The method according to claim 3, wherein the access signal is transmitted using a transmit signal power that is determined from the one or more channel characteristics.

5. A method used by a subscriber station for accessing a wireless multi-carrier communication system, comprising:

determining one or more channel characteristics that is indicative of a range of the subscriber station from a base station;

selecting an access code that generates an access signal having a peak to average power ratio, using the one or more channel characteristics;

generating an access signal from the access code; and

transmitting the access signal.

6. The method according to claim 5, wherein a relationship of the peak to average power ratio (PAPR) to the one or more channel characteristics is a monotonically decreasing relationship of the PAPR to a range estimate determined from the one or more channel characteristics of each frequency sub-band of the set of frequency sub-band.

7. The method according to claim 5, wherein the access signal is transmitted using a transmit signal power that is determined from the one or more channel characteristics.

8. The method according to claim 7, wherein a relationship of the transmit signal power to the one or more channel characteristics is a monotonically decreasing relationship of a monotonically decreasing relationship of the transmit power to a range estimate determined from the one or more channel characteristics.

9. The method according to claim 5, further comprising:

determining one or more channel characteristics of a frequency sub-band within each of a set of frequency sub-bands;

selecting a frequency sub-band of the set of frequency sub-bands based on the one or more channel characteristics; and

transmitting the access signal on the selected frequency sub-band.

10. A method used by a subscriber station for accessing a wireless multi-carrier communication system, comprising:

determining a desired transmit power for a transmission of an access signal to a base station;

determining whether a transmit power amplifier of the subscriber station has sufficient power output capability to achieve the desired transmit power for an access signal having a relatively high peak to average power ratio within the range of peak to average ratios of a defined set of access signals; and

when the determination is negative, attempting to select an access code that generates an access signal having a peak to average power ratio that is lower than the relatively high peak to average power ratio.

11. A method used by a subscriber station for accessing a wireless multi-carrier communication system, comprising:

determining a desired transmit power for a transmission of an access signal to a base station;

selecting a first access code from a set of access codes;

determining whether a transmit power amplifier of the subscriber station has sufficient power output capability to achieve the desired transmit power for an access signal based on the first access code; and

when the determination is negative, selecting at least a second access code in an attempt to provide an access signal having a peak to average power ratio that is lower than a peak to average power ratio of the access signal based on the first access signal.