Adaptive forward power control and adaptive reverse power control for spread-spectrum communications

• US 7,929,498 B2
• Filed: 02/21/2001
• Issued: 04/19/2011
• Est. Priority Date: 06/30/1995
• Status: Expired due to Fees

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Kowalski, John, Lomp, Gary R., Ozluturk, Fatih M.
• Primary Examiner(s): Sheikh; Ayaz R
• Assistant Examiner(s): Lee; Andrew C
• Application Number:
  US09/789,389
• Publication Number:
  US 20020057659A1
• Time in Patent Office: 3,709 Days
• Field of Search: 370/318, 370/317, 370/455, 370/522, 370/355, 370332-335
• US Class Current: 370/335
• CPC Class Codes: G06F 13/374 using a self-select method with individual priority code comparator
• CPC Class Codes: H03H 17/0226 comprising look-up tables
• CPC Class Codes: H03H 17/06 Non-recursive filters
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04B 1/7075 with code phase acquisition
• CPC Class Codes: H04B 1/70753 Partial phase search
• CPC Class Codes: H04B 1/70755 Setting of lock conditions, e.g. threshold
• CPC Class Codes: H04B 1/70758 Multimode search, i.e. using multiple search strategies
• CPC Class Codes: H04B 1/7077 Multi-step acquisition, e.g. multi-dwell, coarse-fine or validation
• CPC Class Codes: H04B 1/708 Parallel implementation
• CPC Class Codes: H04B 1/7085 using a code tracking loop, e.g. a delay-locked loop
• CPC Class Codes: H04B 1/7093 Matched filter type
• CPC Class Codes: H04B 1/7115 Constructive combining of multi-path signals, i.e. RAKE receivers
• 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 2201/70702 Intercell-related aspects
• CPC Class Codes: H04B 2201/70703 using multiple or variable rates
• CPC Class Codes: H04B 2201/70707 Efficiency-related aspects
• CPC Class Codes: H04B 2201/7071 with dynamic control of receiver resources
• CPC Class Codes: H04B 7/2628 using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA] H04B7/2618 takes precedence
• CPC Class Codes: H04B 7/2637 : for logical channel control
• CPC Class Codes: H04B 7/264 : for data rate control
• CPC Class Codes: H04J 13/16 : Code allocation
• CPC Class Codes: H04L 1/0042 : Encoding specially adapted to other signal generation operation, e.g. in order to reduce transmit distortions, jitter, or to improve signal shape H04L1/0067 takes precedence
• CPC Class Codes: H04L 1/0047 : Decoding adapted to other signal detection operation in conjunction with sequence estimation or equalization H04L25/03286
• CPC Class Codes: H04L 1/0059 : Convolutional codes
• CPC Class Codes: H04L 2027/003 : at baseband only
• CPC Class Codes: H04L 2027/0053 : Closed loops
• CPC Class Codes: H04L 25/0212 : of impulse response
• CPC Class Codes: H04L 27/206 : using a pair of orthogonal carriers, e.g. quadrature carriers
• CPC Class Codes: H04L 27/2332 : using a non-coherent carrier
• CPC Class Codes: H04L 5/1446 : of transmission speed
• CPC Class Codes: H04N 1/00912 : Arrangements for controlling a still picture apparatus or components thereof not otherwise provided for
• CPC Class Codes: H04N 1/3333 : during transmission, input or output of the picture signal; within a single document or page
• CPC Class Codes: H04N 2201/3335 : Speed or rate
• CPC Class Codes: H04W 52/08 : Closed loop power control
• CPC Class Codes: H04W 52/146 : Uplink power control
• CPC Class Codes: H04W 52/24 : using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 52/26 : using transmission rate or quality of service QoS [Quality of Service]
• CPC Class Codes: H04W 52/322 : Power control of broadcast channels
• CPC Class Codes: H04W 52/325 : Power control of control or pilot channels
• CPC Class Codes: H04W 52/343 : taking into account loading or congestion level
• CPC Class Codes: H04W 52/36 : with a discrete range or set of values, e.g. step size, ramping or offsets
• CPC Class Codes: H04W 52/362 : Aspects of the step size
• CPC Class Codes: H04W 52/367 : Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 52/44 : in connection with interruption of transmission
• CPC Class Codes: H04W 52/50 : at the moment of starting communication in a multiple access environment
• CPC Class Codes: H04W 52/52 : using AGC [Automatic Gain Control] circuits or amplifiers
• CPC Class Codes: H04W 52/54 : Signalisation aspects of the TPC commands, e.g. frame structure
• CPC Class Codes: H04W 52/60 : using different transmission rates for TPC commands

Abstract

A wireless code division multiple access (CDMA) communication system, including a base station (BS) and a subscriber unit (SU), uses adaptive forward power control (AFPC) and adaptive reverse power control (ARPC) to control the transmit power of forward and reverse link radio frequency (RF) channel signals, respectively. Automatic gain control (AGC) signals are produced to maintain the level of forward and reverse CDMA signals at a near constant level. The CDMA signals are despread to produce first and second despread signals. The first and second despread signals are used to produce a first error signal e₁. A second error signal e₂ is produced based on the AGC signals. Combined error signals are formed based on the first error signal e₁ and the second error signal e₂. The combined error signals are hard limited to form adaptive power control (APC) bits used to control the level of the forward and reverse link RF channel signals.

Claims

1. A transmission circuit configured to spread code a first data and a second data in accordance with two different corresponding spreading codes, a first spreading code and a second spreading code;

the transmission circuit further being configured to output the spread first data using a first spreading code on a first channel and spread second data using a second spreading code on a second channel, respectively, the first channel derived from the first data using the first spreading code at a first data rate, and the second channel derived from the second data using the second spreading code at a second data rate, the first and second data rates being different from one another, wherein the transmission circuit is further configured to output a third channel, which does not carry the first and second data, the third channel derived by spread coding a power control bit and signaling information with a corresponding spreading code, the signaling information facilitating the processing of radio frequency signals by a base station, wherein the transmission circuit is further configured to combine the first channel, the second channel and the third channel; and

an antenna coupled to the transmission circuit, the antenna outputting a radio frequency signal derived from the combined the first, the second and the third channels;

wherein the first channel, the second channel and the third channel are transmitted at the same time, wherein the transmission circuit is further configured to determine the power control bit based on a power level of a channel received by the antenna and an interference or a noise level associated with the received channel.

2. The code division multiple access subscriber unit in accordance with claim 1, wherein the power control bit is one of a plurality of power control bits, and wherein the transmission circuit is further configured to time division multiplex the plurality of power control bits with the signaling information onto the third channel.

3. The code division multiple access subscriber unit in accordance with claim 1, wherein the power control bit is one of a plurality of power control bits that are not error protected.

4. The code division multiple access subscriber unit in accordance with claim 1, wherein the power control bit is one of a plurality of power control bits that are not subject to forward error correction encoding.

5. The code division multiple access subscriber unit in accordance with claim 1, wherein the subscriber unit further comprises:

a first interface coupled to the transmission circuit; and

a second interface coupled to the transmission circuit, the first interface receiving the first data and the second interface receiving the second data.

6. A communication method for use in a code division multiple access (CDMA) subscriber unit, comprising:

producing a first data and a second data;

spread coding the first data and the second data in accordance with two different corresponding spreading codes, a first spreading code and a second spreading code;

outputting the spread coded first data using a first spreading code on a first channel and second data using a second spreading code on a second channel, respectively;

spread coding combining a power control bit and signaling information with a corresponding spreading code to produce a third channel, such that the third channel does not carry the first and second data, the signaling information facilitating processing of radio frequency signals by a base station;

combining the first channel, the second channel, and the third channel; and

transmitting, with an antenna of the code division multiple access subscriber unit, a radio frequency signal that is derived from the combined the first, second and third channels, such that a first data rate associated with the first data carried by the first channel is different than a second data rate associated with the second data carried by the second channel, wherein the first, second and third channels are transmitted at the same time, wherein the transmission circuit is further configured to determine the power control bit based on a power level of a channel received by the antenna and an interference or a noise level associated with the received channel.

7. The communication method in accordance with claim 6, wherein the power control bit is one of a plurality of power control bits, and the combining includes time division multiplexing the plurality of power control bits with the signaling information onto the second channel.

8. The communication method in accordance with claim 6, wherein the power control bit is one of a plurality of power control bits that are not error protected.

9. The communication method in accordance with claim 6, wherein the power control bit is one of a plurality of power control bits that are not subject to forward error correction encoding.

10. The communication method in accordance with claim 6, further comprising receiving the first data through a first interface of the code division multiple access subscriber unit and receiving the second data through a second interface of the code division multiple access subscriber unit, the first data including first digital data and the second data including second digital data.

11. The communication method in accordance with claim 10, wherein the first digital data includes a plurality of frames.

12. A code division multiple access subscriber unit, comprising:

a transmission circuit configured to spread code a first data and a second data in accordance with two different corresponding spreading codes, a first spreading code and a second spreading code,

the transmission circuit further being configured to output the spread first data using a first spreading code on a first channel and spread second data using a second spreading code on a second channel, respectively, the first channel derived from the first data using the first spreading code at a first data rate, and the second channel derived from the second data using the spreading code at a second data rate, the first and second data rates being different from one another,

wherein the transmission circuit is further configured to output a third channel that does not carry the first and second data, the third channel including derived by spread coding a power control bit and signaling information with a corresponding spreading code, the signaling information facilitating the processing of radio frequency signals by a base station, wherein the transmission circuit is further configured to combine the first channel, the second channel and the third channel; and

an antenna coupled to the transmission circuit, and configured to transmit a radio frequency signal derived from the combined the first, second and third channels, wherein the first, the second and the third channels are transmitted at the same time, wherein the transmission circuit is further configured to determine the power control bit based on a power level of a channel received by the antenna and an interference or a noise level associated with the received channel.

13. The code division multiple access subscriber unit in accordance with claim 12, wherein the power control bit is one of a plurality of power control bits, and wherein the transmission circuit is further configured to time division multiplex the plurality of power control bits with the signaling information onto the third channel.

14. The code division multiple access subscriber unit in accordance with claim 12, wherein the power control bit is one of a plurality of power control bits that are not error protected.

15. The code division multiple access subscriber unit in accordance with claim 12, wherein the power control bit is one of a plurality of power control bits that are not subject to forward error correction encoding.

16. The code division multiple access subscriber unit in accordance with claim 12, wherein the subscriber unit further includes:

a first interface coupled to the transmission circuit; and

a second interface coupled to the transmission circuit, the first interface receiving the first data and the second interface receiving the second data that comprise first and second digital data, respectively.

17. The code division multiple access subscriber unit in accordance with claim 16, wherein the first digital data includes a plurality of frames.