Apparatus and method for transforming a signal in a frequency domain to a sequence in a time domain

Patent metadata

Field	Value
Publication number	US-10484994-B2
Application number	US-201816209172-A
Country	US
Kind code	B2
Filing date	Dec 4, 2018
Priority date	Sep 22, 2008
Publication date	Nov 19, 2019
Grant date	Nov 19, 2019

Abstract

A communication apparatus includes a receiver, a combiner, and a transformer. The receiver receives signals mapped on plural frequency bands. A size of at least one of the frequency bands is a multiple of a product of two or more powers of prime numbers, which are integer numbers greater than 1 and are different from each other. An exponent for at least one of the prime numbers is an integer greater than 1. The combiner combines the received signals into a combined signal. The transformer transforms the combined signal in a frequency domain into a symbol sequence in a time domain with an inverse discrete Fourier transform (IDFT) having a size that is a product of powers of plural values. The values are integer numbers greater than 1 and are different from each other. An exponent for at least one of the values is an integer greater than 1.

First claim

The invention claimed is:

1. A communication apparatus comprising:
a receiver which receives signals mapped on a plurality of frequency bands in a frequency domain, each frequency band being located at a position separate from position(s) of other(s) of the plurality of frequency bands, wherein vector lengths corresponding to sizes of the plurality of frequency bands are each a product of two or more powers of prime numbers or a multiple of the product of the two or more powers of prime numbers, the prime numbers being integer numbers that are greater than 1 and are different from each other, exponents for the prime numbers being a set of non-negative integers, wherein the vector length is a number of subcarriers allocated to a corresponding one of the plurality of frequency bands;
a combiner which combines the received signals into a combined signal; and
a transformer which transforms the combined signal in the frequency domain into a symbol sequence in a time domain with an inverse discrete Fourier transform (IDFT) having a size that is a product of powers of a plurality of values, the plurality of values being integer numbers that are greater than 1 and are different from each other, exponents for the plurality of values being a set of non-negative integers.

2. The communication apparatus according to claim 1 , wherein a number of the plurality of frequency bands is two, and a size of one of the two frequency bands is a multiple of a product of two or more powers of prime numbers.

3. The communication apparatus according to claim 1 , wherein the prime numbers are selected in order from a smaller prime number.

4. The communication apparatus according to claim 1 , wherein a size of all of the plurality of frequency bands is a multiple of a product of two or more powers of prime numbers.

5. The communication apparatus according to claim 1 , wherein a first exponent for a first prime number is equal to or greater than a second exponent for a second prime number that is greater than the first prime number.

6. The communication apparatus according to claim 1 , wherein a size of each of the plurality of frequency bands is one minimum division unit or multiple minimum division units, wherein the minimum division unit is a minimum number of subcarriers that form each of the plurality of frequency bands and is a product of two or more powers of prime numbers.

7. The communication apparatus according to claim 6 , wherein a size of all of the plurality of frequency bands is a multiple of the minimum division unit.

8. The communication apparatus according to claim 7 , further comprising:
a transmitter which transmits allocation information indicating a frequency position of each of the plurality of frequency bands, the frequency position being indicated in terms of the minimum division unit.

9. The communication apparatus according to claim 1 , further comprising:
a transmitter which transmits allocation information including the size of at least one of the plurality of frequency bands.

10. A communication method performed by a communication apparatus comprising:
receiving signals mapped on a plurality of frequency bands in a frequency domain, each frequency band being located at a position separate from position(s) of other(s) of the plurality of frequency bands, wherein vector lengths corresponding to sizes of the plurality of frequency bands are each a product of two or more powers of prime numbers or a multiple of the product of the two or more powers of prime numbers, the prime numbers being integer numbers that are greater than 1 and are different from each other, exponents for the prime numbers being a set of non-negative integers, wherein the vector length is a number of subcarriers allocated to a corresponding one of the plurality of frequency bands;
combining the received signals into a combined signal; and
transforming the combined signal in the frequency domain into a symbol sequence in a time domain with an inverse discrete Fourier transform (IDFT) having a size that is a product of powers of a plurality of values, the plurality of values being integer numbers that are greater than 1 and are different from each other, exponents for the plurality of values being a set of non-negative integers.

11. The communication method according to claim 10 , wherein a number of the plurality of frequency bands is two, and a size of one of the two frequency bands is a multiple of a product of two or more powers of prime numbers.

12. The communication method according to claim 10 , wherein the prime numbers are selected in order from a smaller prime number.

13. The communication method according to claim 10 , wherein a size of all of the plurality of frequency bands is a multiple of a product of two or more powers of prime numbers.

14. The communication method according to claim 10 , wherein a first exponent for a first prime number is equal to or greater than a second exponent for a second prime number that is greater than the first prime number.

15. The communication method according to claim 10 , wherein a size of each of the plurality of frequency bands is one minimum division unit or multiple minimum division units, wherein the minimum division unit is a minimum number of subcarriers that form each of the plurality of frequency bands and is a product of two or more powers of prime numbers.

16. The communication method according to claim 15 , wherein a size of all of the plurality of frequency bands is a multiple of the minimum division unit.

17. The communication method according to claim 16 , further comprising:
transmitting allocation information indicating a frequency position of each of the plurality of frequency bands, the frequency position being indicated in terms of the minimum division unit.

18. The communication method according to claim 10 , further comprising:
transmitting allocation information including the size of at least one of the plurality of frequency bands.

Assignees

• Sun Patent Trust

Inventors

• Takaoka Shinsuke
• Hoshino Masayuki
• Miyoshi Kenichi

Classifications

• H04J4/005

  Transmultiplexing · CPC title

• H04W88/08

  Access point devices · CPC title

• Y10S370/916

  Multiplexer/demultiplexer · CPC title

• H04L27/26 Primary

  Systems using multi-frequency codes (H04L27/32 takes precedence) · CPC title

• G06F17/141

  Discrete Fourier transforms · CPC title