Wireless Communication Apparatus, Mobile Terminal and Wireless Communication Method

• US 20120082254A1
• Filed: 10/12/2011
• Published: 04/05/2012
• Est. Priority Date: 01/18/2005
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: KASHIWAGI, Hiroki, HAMAGUCHI, Yasuhiro
• Granted Patent: US 8,279,809 B2
• Time in Patent Office: Days
• US Class Current: 375/260
• CPC Class Codes: H04J 1/00 Frequency-division multiplex systems H04J14/00 takes precedence
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/0064 Rate requirement of the data, e.g. scalable bandwidth, data priority
• CPC Class Codes: H04L 5/0066 Requirements on out-of-channel emissions
• CPC Class Codes: H04W 52/0212 managed by the network, e.g. network or access point is master and terminal is slave
• CPC Class Codes: H04W 52/16 Deriving transmission power values from another channel
• CPC Class Codes: H04W 52/247 where the output power of a terminal is based on a path parameter sent by another terminal
• CPC Class Codes: H04W 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 72/0473 the resource being transmission power
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/51 based on terminal or device properties
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Wireless communication with a communicating apparatus that is a limited band terminal capable of receiving only part of frequencies. A frequency channel allocating section allocates frequency channels, a terminal reception quality information processing section calculates an optimal modulation rate and required transmit power for each subcarrier, a subcarrier power control section controls a level of transmit power for each subcarrier, and a determining section checks a reception bandwidth of a communicating apparatus, while determining whether the communicating apparatus is a full band terminal capable of receiving all the frequency channels in the system band or a limited band terminal capable of receiving only part of frequencies. When the communicating apparatus is the limited band terminal, the transmit power of all or part of subcarriers is decreased in a frequency channel that is adjacent to a reception band allocated to the communicating apparatus and that is allocated to another communicating apparatus.

Claims

1. An apparatus operable for transmitting orthogonal frequency division multiplexing (OFDM) signals for communication in a wireless communication system, the apparatus comprising:

one or more signal reception components for receiving a signal indicating reception capabilities of another apparatus operable for communication in the wireless communication system;

signal generation and transmission components for generating and transmitting to the other device an OFDM signal comprising a plurality of subcarriers arranged in a frequency channel;

wherein the signal generation and transmission components allocate substantially no power to a first arbitrary number of subcarriers at a first edge of the frequency channel and a second arbitrary number of subcarriers at a second edge of the frequency channel; and

wherein the first arbitrary number of subcarriers and the second arbitrary number of subcarriers are determined as a function of the reception capabilities of the other apparatus, wherein the reception capabilities indicate that the first arbitrary number of subcarriers and the second arbitrary number of subcarriers are not usable by the other apparatus.

2. The apparatus of claim 1, wherein the frequency channel comprises a plurality of adjacent frequency channels.

3. The apparatus of claim 1, wherein the signal generation and transmission components determine whether the frequency channel comprises a single frequency channel or a plurality of adjacent frequency channels based on the reception capabilities of the other apparatus.

4. The apparatus of claim 1, wherein the other apparatus comprises a base station.

5. The apparatus of claim 1, wherein the other apparatus comprises a mobile terminal.

6. An apparatus operable for transmitting orthogonal frequency division multiplexing (OFDM) signals for communication in a wireless communication system, the apparatus comprising:

one or more signal reception components for receiving a signal indicating reception capabilities of another apparatus operable for communication in the wireless communication system;

signal generation and transmission components for generating and transmitting to the other device an OFDM signal comprising a plurality of subcarriers arranged in a frequency channel;

wherein the signal generation and transmission components allocate substantially no power to a first arbitrary number of subcarriers at a first edge of the frequency channel and a second arbitrary number of subcarriers at a second edge of the frequency channel; and

wherein the first arbitrary number of subcarriers and the second arbitrary number of subcarriers are determined as a function of the reception capabilities of the other apparatus, wherein the reception capabilities indicate that the first arbitrary number of subcarriers and the second arbitrary number of subcarriers are always not usable by the other apparatus.

7. The apparatus of claim 6, wherein the frequency channel comprises a plurality of adjacent frequency channels.

8. The apparatus of claim 6, wherein the signal generation and transmission components determine whether the frequency channel comprises a single frequency channel or a plurality of adjacent frequency channels based on the reception capabilities of the other apparatus.

9. The apparatus of claim 6, wherein the other apparatus comprises a base station.

10. The apparatus of claim 6, wherein the other apparatus comprises a mobile terminal.

11. A method for generating orthogonal frequency division multiplexing (OFDM) signals for communication in a wireless communication system, the method comprising:

receiving a signal indicating reception capabilities of an apparatus operable for communication in the wireless communication system;

generating an OFDM signal comprising a plurality of subcarriers arranged in a frequency channel;

determining based on the reception capabilities of the apparatus that a first arbitrary number of subcarriers at a first edge of the frequency channel and a second arbitrary number of subcarriers at a second edge of the frequency channel are not usable by the apparatus;

allocating substantially no power to the first arbitrary number of subcarriers and the second arbitrary number of subcarriers; and

transmitting the OFDM signal to the apparatus.

12. The method of claim 11, wherein the frequency channel comprises a plurality of adjacent frequency channels.

13. The method of claim 11, further comprising determining whether the frequency channel comprises a single frequency channel or a plurality of adjacent frequency channels based on the reception capabilities of the apparatus.

14. The method of claim 11, wherein the apparatus comprises a base station.

15. The method of claim 11, wherein the apparatus comprises a mobile terminal.

16. The method of claim 11, wherein determining that the first arbitrary number of subcarriers and the second arbitrary number of subcarriers are not usable by the apparatus comprises determining that the first arbitrary number of subcarriers and the second arbitrary number of subcarriers are always not usable by the apparatus.