Distortion compensation address generator, distortion compensating circuit, and transmitter

• US 6,272,326 B1
• Filed: 07/12/1999
• Issued: 08/07/2001
• Est. Priority Date: 07/13/1998
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Shinde, Hiroki
• Primary Examiner(s): Maung, Nay
• Assistant Examiner(s): Trinh, Sonny
• Application Number:
  US09/351,170
• Time in Patent Office: 757 Days
• Field of Search: 455/114, 455/127, 455/126, 455/311, 455/341, 455/63, 455/522, 455/91, 330/2, 330/149, 375/296, 375/297, 375/284, 375/285
• US Class Current: 455/127.1
• CPC Class Codes: H04L 27/367 using predistortion

Abstract

An address generator for compensating non-linear distortion of a transmitting amplifier according to this invention comprises transmission power calculation means for calculating transmission power based on transmission data, a comparator control circuit, and an address generation table. The address generation table comprises a plurality of comparators operating in parallel. The comparator control circuit turns on only necessary comparators based on the transmission power value so as to reduce power consumption.

Claims

1. A distortion compensation address generator for generating an address designating a storage area of compensation data for compensating non-linear distortion of a transmitting amplifier comprising:

a plurality of comparators each for comparing a transmission power value with a respective predetermined reference value;

a decoder for decoding an output of each of said plurality of comparators; and

comparator control means for turning off a part of said plurality of comparators being not used in generation of said address, corresponding to a level of said transmission power value.

2. The distortion compensation address generator according to claim 1, wherein said comparator control means compares transmission power value with an operation area coefficient prepared in advance in order to generates a control signal for turning off the part of said comparators.

3. The distortion compensation address generator according to claim 1, further comprising transmission power calculation means for calculating said transmission power value based on transmission data.

4. The distortion compensation address generator according to claim 3, wherein said transmission power calculation means combines a plurality of transmission signals so as to calculate transmission power.

16. A distortion compensation circuit comprising:

a distortion compensation address generator described in claim 1;

distortion compensation data storage means to which an address signal outputted from said distortion compensation address generator is inputted so as to output corresponding distortion compensation data; and

a compensating circuit for compensating distortion of a transmitting signal using said distortion compensation data outputted from said distortion compensation data storage means.

5. A distortion compensation address generator for generating an address designating a storage area of compensation data for compensating non-linear distortion of a transmitting amplifier comprising:

an address generation table having a plurality of comparators each for comparing a transmission power value with a respective predetermined reference value;

a decoder for decoding an output of each of said plurality of comparators; and

comparator control means for turning off a part of said plurality of comparators being not used in generation of said address, corresponding to a level of said transmission power value;

an address calculator for providing a predetermined calculation to said transmission power value so as to generate said address; and

a switching circuit compares said transmission power value with a predetermined threshold value in order to turn on either said address generation table or said address calculator in accordance with a comparison result.

6. The distortion compensation address generator according to claim 5, wherein said switching circuit turns on said address generation table when said transmission power value is smaller than said threshold value and turns on said address calculator when said transmission power is greater than said threshold value.

7. The distortion compensation address generator according to claim 5, wherein said address calculator has a function of executing an addition, a multiplication, and a division.

8. The distortion compensation address generator according to claim 7, wherein said address calculator performs the division by a bit shift operation.

9. The distortion compensation address generator according to claim 5, further comprising transmission power calculation means for calculating said transmission power value based on transmission data.

10. The distortion compensation address generator according to claim 9, wherein said transmission power calculation means combines a plurality of transmission signals so as to calculate transmission power.

11. A distortion compensation address generator for generating an address designating a storage area of compensation data for compensating non-linear distortion of a transmitting amplifier comprising:

transmission power calculation means for calculating transmission power of a transmitting signal;

a plurality of address generation tables, to each of which a transmission power value calculated by said transmission power calculation means is inputted, being selectively switched;

an address calculator with a plurality of calculation coefficient tables, for executing with respect to the transmission power value of the transmitting signal a predetermined calculation using coefficient values of one pair of the calculation coefficient tables selected from said plurality of calculation coefficient tables, thereby allowing rating said address to be generated;

table selecting means for selecting one address generation table from said plurality of address generation tables and one pair of calculation coefficient tables from said plurality of calculation coefficient tables, corresponding to a transmission power level of said transmitting amplifier; and

a switching circuit for comparing said transmission power value with a predetermined threshold value to turn on either said address generation table or said address calculator, corresponding to a comparison result,

wherein each of said plurality of address generation table has a plurality of comparators for comparing said transmission power value with a predetermined reference value;

a decoder for decoding an output of each of said plurality of comparators; and

comparator control means for turning off-a part of said plurality of comparators being not used in generation of said address, corresponding to a level of said transmission power value.

12. The distortion compensation address generator according to claim 11, wherein said transmission power calculation means combines a plurality of transmission signals so as to calculate transmission power.

13. The distortion compensation address generator according to claim 11, wherein said switching circuit turns on said address generation table when said transmission power value is smaller than a threshold value and turns on said address calculator when said transmission power value is greater than said threshold value.

14. The distortion compensation address generator according to claim 11, wherein said address calculator has a function of executing an addition, a multiplication, and a division.

15. The distortion compensation address generator according to claim 14, wherein said address calculator performs the division by a bit shift operation.

17. A transmitter comprising:

a spread processing section for performing spectrum spread by multiplying data to be transmitted by a specific code;

a distortion compensation address generator having a plurality of comparators each for comparing a transmission power value with a respective predetermined reference value;

a decoder for decoding an output of each of said plurality of comparators; and

comparator control means for turning off a part of said plurality of comparators being not used in generation of said address corresponding to a level of said transmission power value;

distortion compensation data storage means to which an address signal outputted from said distortion compensation address generator is inputted so as to output corresponding distortion compensation data;

a compensating circuit for compensating for distortion of data passed through said spread processing section using said distortion compensation data outputted from said distortion compensation data storing means;

a transmitting amplifier for amplifying a transmitting signal obtained based on data output from said compensating circuit; and

an antenna for outputting an output of said transmitting amplifier as a radio signal.

18. The transmitter according to claim 17, further comprising transmission power designating means for designating transmission power with respect to said transmitting amplifier and said distortion compensation address generator.

21. A mobile station apparatus including the transmitter described in claim 17.

22. A base station apparatus including the transmitter described in any one of claims 17 to 20.

19. A transmitter comprising:

a time division multiplex processing section for performing time division multiplex processing;

a distortion compensation address generator having a plurality of comparators each for comparing a transmission power value with a respective predetermined reference value;

a decoder for decoding an output of each of said plurality of comparators; and

comparator control means for turning off a part of said plurality of comparators being not used in generation of said address, corresponding to a level of said transmission power value;

distortion compensation data storage means to which an address signal outputted from said distortion compensation address generator is inputted so as to output corresponding distortion compensation data;

a compensating circuit for compensating distortion of data passed through said time division multiplex processing section using said distortion compensation data outputted from said distortion compensation data storing means;

a transmitting amplifier for amplifying a transmitting signal obtained based on data outputted from said compensating circuit; and

an antenna for outputting an output of said transmitting amplifier as a radio signal.

20. The transmitter according to claim 19, further comprising transmission power designating means for designating transmission power to said transmitting amplifier and said distortion compensation address generator.