Base station using global channel power control

• US 20060264230A1
• Filed: 07/27/2006
• Published: 11/23/2006
• Est. Priority Date: 02/12/1997
• Status: Abandoned Application

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Ozluturk, Fatih M.
• Application Number:
  US11/493,948
• Publication Number:
  US 20060264230A1
• Time in Patent Office: Days
• US Class Current: 455/522
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/16 Deriving transmission power values from another channel
• CPC Class Codes: H04W 52/24 using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 52/32 TPC of broadcast or control channels
• CPC Class Codes: H04W 52/322 Power control of broadcast channels
• CPC Class Codes: H04W 52/343 taking into account loading or congestion level
• CPC Class Codes: H04W 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A wireless spread spectrum base station has a plurality of modems. The modems produce at least one baseband channel signal and a baseband reference signal. At least one forward power controller controls a power level of the at least one baseband channel signal. A baseband signal combiner combines the at least one baseband channel and baseband reference signals. A radio frequency transmitter modulates to radio frequency and transmits the combined signal. A reference power control processor determines a desired transmit power level of the baseband reference signal to the desired transmit power level.

Claims

1. In a cellular wireless communication system including a plurality of base stations and wireless transmit/receive units (WTRUs) wherein each base station transmits a reference signal over an entire range of a cell, a method for controlling transmit power of the reference signal, the method comprising:

a base station measuring a total transmit power level of combined signals on a channel specifically assigned to a WTRU and a reference signal; and

the base station adjusting a transmit power level of the reference signal based on the total transmit power level of the combined signals.

2. The method of claim 1, wherein the total transmit power level is measured after combining signals on a channel specifically assigned to a WTRU and the reference signal.

3. The method of claim 1, wherein individual transmit power levels are measured at each assigned channel and a reference channel, and the total transmit power level is measured by summing the individual transmit power levels.

4. The method of claim 1, wherein the total transmit power level is measured after transmission of combined signals on a channel specifically assigned to a WTRU and the reference signal.

5. The method of claim 1, wherein the transmit power level of the reference signal is determined based on at least one of:

a desired signal-to-noise ratio (SNR), a processing gain, a transmit bandwidth, a noise density, a cell radius, and a carrier frequency.

6. The method of claim 1, wherein the transmit power level of the reference signal is determined using at least one of:

a free space propagation model, a Hata model, and a break-point model.

7. The method of claim 1, wherein the transmit power level of the reference signal is adjusted continuously.

8. The method of claim 1, wherein the transmit power level of the reference signal is adjusted on a periodic basis.

9. In a cellular wireless communication system including a plurality of base stations and wireless transmit/receive units (WTRUs) wherein each base station transmits a reference signal over an entire range of a cell, an apparatus for controlling transmit power of the reference signal, the apparatus comprising:

a transmit power measurement unit configured to measure a total transmit power level of combined signals on a channel specifically assigned to a WTRU and a reference signal; and

a reference channel power control processor configured to adjust a transmit power level of the reference signal based on the total transmit power level of the combined signals.

10. The apparatus of claim 9, wherein the transmit power measurement unit is configured to measure the total transmit power level after combining signals.

11. The apparatus of claim 9, wherein the transmit power measurement unit is configured to:

measure individual transmit power levels at each assigned channel and a reference channel; and

sum the individual transmit power levels to calculate the total transmit power level.

12. The apparatus of claim 9, wherein the transmit power measurement unit is configured to measure the total transmit power level after transmission of the combined signals.

13. The apparatus of claim 9, wherein the reference channel power control processor is configured to determine the transmit power level of the reference signal based on at least one of:

a desired signal-to-noise ratio (SNR), a processing gain, a transmit bandwidth, a noise density, a cell radius, and a carrier frequency.

14. The apparatus of claim 9, wherein the reference channel power control processor is configured to determine the transmit power level of the reference signal using at least one of:

a free space propagation model, a Hata model, and a break-point model.

15. The apparatus of claim 9, wherein the reference channel power control processor is configured to adjust the transmit power level of the reference signal continuously.

16. The apparatus of claim 9, wherein the reference channel power control processor is configured to adjust the transmit power level of the reference signal on a periodic basis.