Communication system, communication terminal, and communication method

• US 20060153114A1
• Filed: 11/22/2005
• Published: 07/13/2006
• Est. Priority Date: 11/26/2004
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Tanaka, Hironori, Sakamoto, Kazuhiko
• Granted Patent: US 7,855,986 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0277 according to available power supply, e.g. switching off when a low battery condition is detected
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A communication terminal, in case that transmission/reception of a frame is carried out between a management terminal and another communication terminal, reads out its frame content, and on the basis of a content of the frame which was readout, sets up power off time for turning off power of the communication terminal, and turns off power of the communication terminal, during a period of the power off time. By this means, depending on a content of a frame which is transmitted/received between another communication terminal and the management terminal, power off time of the communication terminal is calculated, and therefore, it is possible to turn off power of the communication terminal during such a period that transmission/reception is not carried out to/from the management terminal, and it is possible to suppress power consumption of the communication terminal.

Claims

1. A communication system comprising:

a management terminal connected to a first network; and

a plurality of communication terminals connected to the management terminal through a second network, the management terminal managing transmission/reception of a frame to/from each communication terminal through the second network,

wherein the communication terminal comprises;

a frame reception section which, in case of transmitting/receiving a frame between the management terminal and the communication terminal, receives the frame;

a frame content readout section which reads out a content stored in the frame which was received by the frame reception section;

a power off time setup section which sets up power off time for turning off power of the communication terminal, on the basis of a content of the frame which was read out by the frame content readout section; and

a power off section which turns off power of the communication terminal, during a period of the power off time which was set up by the power off time setup section.

2. The communication system according to claim 1,

wherein the communication terminal further comprises a time judgment section which judges whether the power off time, which was set up by the power off time setup section, exceeded predetermined time or not, and

wherein the power off section, in case that it was judged by the time judgment section that the power off time exceeded the predetermined time, turns off power of the communication terminal, during a period of the power off time.

3. The communication system according to claim 1,

wherein the frame content readout section reads out contents of a header, a frame body and FCS of the frame received by the frame reception section.

4. The communication system according to claim 1,

wherein the power off time setup section has a power off time calculation section which calculates transmission time of the frame,

wherein the frame content readout section reads out such a frame sequence that a plurality of frames continue in terms of time, from the frame received by the frame reception section,

wherein the power off time calculation section calculates transmission time of the frame sequence which was read out by the frame content readout section, and

wherein the power off section turns off power of the communication terminal, during a period of the transmission time which was calculated by the power off time calculation section.

5. The communication system according to claim 4,

wherein the frame includes a beacon which shows that the frame sequence continues, and

wherein the frame content readout section reads out the frame sequence in which the plurality of frames continue in terms of time, only from the beacon.

6. The communication system according to claim 1,

wherein the frame content readout section reads out a content which was stored in a header of a frame received by the frame reception section.

7. The communication system according to claim 6,

wherein the header of the frame comprises a physical header.

8. The communication system according to claim 1,

wherein the frame includes information of a processing order and allocation time of each communication terminal,

wherein the frame content readout section reads out when a frame sequence is started, from the frame received by the frame reception section,

wherein the power off time calculation section calculates start time of the frame sequence which was read out by the frame content readout section, and

wherein the power off section turns off power of the communication terminal, until the start time which was calculated by the power off time calculation section.

9. A communication terminal which transmits/receives a frame to/from a management terminal which is connected to a first network, through a second network, comprising:

a frame reception section which, in case of transmitting/receiving a frame between the management terminal and the communication terminal, receives the frame;

a frame content readout section which reads out a content stored in the frame which was received by the frame reception section;

a power off time setup section which sets up power off time for turning off power of the communication terminal, on the basis of a content of the frame which was read out by the frame content readout section; and

a power off section which turns off power of the communication terminal, during a period of the power off time which was set up by the power off time setup section.

10. A communication method in which a management terminal connected to a first network is transmitting/receiving a frame to/from a plurality of communication terminals through a second network,

wherein the communication terminal comprises:

receiving, in case of transmitting/receiving a frame between the management terminal and the communication terminal, the frame;

reading out a content which was stored in the received frame;

setting up power off time for turning off power of the communication terminal, on the basis of a content of the frame which was read out; and

turning off power of the communication terminal, during a period of the power off time which was set up.

11. A communication system comprising a communication terminal and a management terminal which manages the communication terminal,

wherein the management terminal comprises a communication unit which transmits a reference frame including frame stored information which shows that there exists a frame addressed to the communication terminal, to the communication terminal, and

wherein the communication terminal comprises:

a communication unit which receives the reference frame; and

a power control unit which turns off power, in case that the frame stored information is not included in the reference frame received by the communication unit of the communication terminal, after it turns on power in tune with timing of receiving the reference frame from the management terminal.

12. The communication system according to claim 11,

wherein the power control unit of the communication terminal turns on power in tune with timing of receiving the reference frame from the management terminal, and turns off power, after transmission/reception of a frame to/from the management terminal is completed, in case that the frame stored information is included in the reference frame which was received by the reception unit.

13. The communication system according to claim 11,

wherein the communication system comprises a plurality of communication terminals;

and

wherein the communication unit of the management terminal transmits the reference frame which includes the frame stored information, to a part of communication terminals among the plurality of communication terminals.

14. A communication system comprising a plurality of communication terminals and a management terminal which manages the communication terminals,

wherein the management terminal comprises:

a processing order determination unit which determines a processing order from a reference frame; and

a communication unit which carries out communication with each communication terminal in accordance with the processing order which was determined by the processing order determination unit, and

wherein the communication terminal comprises;

a communication unit which receives the reference frame; and

a power control unit which turns off power, after transmission/reception of a frame to/from the management terminal is completed, after it turns on power in tune with timing of receiving the reference frame from the management terminal.

15. The communication system according to claim 14,

wherein the management terminal further comprises a processing unit which carries out processing of a frame to each communication terminal, in accordance with such an order that communication was started, when the communication unit starts communication.

16. The communication system according to claim 14,

wherein the management terminal further comprises a storage unit which stores power on cumulative time on the basis of reference time, and

wherein the processing order determination unit determines the processing order, on the basis of the power on cumulative time which is stored by the storage unit.

17. The communication system according to claim 14,

wherein the management terminal further comprises a battery remaining quantity obtaining unit which obtains battery remaining quantity from each of the plurality of communication terminals, and

wherein the processing order determination unit determines the processing order, on the basis of the battery remaining quantity which was obtained by the battery remaining quantity obtaining unit.