Wireless Communication Unit, Power Control Method for Wireless Communication Unit and Wireless Network

• US 20090156245A1
• Filed: 09/11/2006
• Published: 06/18/2009
• Est. Priority Date: 09/16/2005
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Yano, Hitoshi
• Granted Patent: US 7,899,435 B2
• Time in Patent Office: Days
• US Class Current: 455/517
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

The present invention, which is aimed at providing a wireless communication unit which is operated by battery power and offers long battery life, power control method thereof and a wireless network which utilizes the wireless communication unit, includes: a direct demodulation standby part for prestoring an own unit identification code to compare the identification code included in the high-frequency signal with the own unit identification code; an intermittent power supply part for intermittently supplying power to the direct demodulation standby part; and a power control part for controlling the power supply to the transmitting/receiving part, wherein the direct demodulation standby part notifies the power control part and the intermittent power supply part, whether or not the identification code coincides with the own unit identification code after comparing the both, the power control part supplies power to the transmitting/receiving part upon receiving the notification from the direct demodulation standby part, indicating that the identification code coincides with the own unit identification code, and the intermittent power supply part intermittently supplies power to the direct demodulation standby part upon receiving the notification from the direct demodulation standby part indicating that the identification code does not coincide with the own unit identification code.

Claims

1. A wireless communication unit comprising a transmitting-receiving part which transmits and receives a high-frequency signal including an identification code for individually identifying the wireless communication unit, said wireless communication unit comprising:

a direct demodulation standby part for prestoring an own unit identification code which indicates said identification code of its own, and for demodulating said high-frequency signal to compare said identification code included in said high-frequency signal with said own unit identification code;

an intermittent power supply part for intermittently supplying power to said direct demodulation standby part; and

a power control part for controlling the power supply to said transmitting/receiving part, wherein

said direct demodulation standby part notifies, to said power control part and said intermittent power supply part, whether or not said identification code coincides with said own unit identification code after comparing the both,

said power control part supplies power to said transmitting/receiving part upon receiving a notification from said direct demodulation standby part, indicating that said identification code coincides with said own unit identification code, and

said intermittent power supply part intermittently supplies power to said direct demodulation standby part upon receiving a notification indicating that said identification code does not coincide with said own unit identification code, from said direct demodulation standby part.

2. The wireless communication unit according to claim 1, wherein

said direct demodulation standby part comprises:

a power divider for power dividing said received high-frequency signal,

a delay element for delaying said high-frequency signal power divided by said power divider,

an analog multiplier for being inputted together with said power divided high-frequency signal and the high-frequency signal delayed by said delay element to multiply them together and for outputting a multiplication signal, and

a filter for removing a high-frequency component from said multiplication signal outputted from said analog multiplier to output a direct demodulation signal including said identification code of said wireless communication unit, wherein

said direct demodulation signal outputted from said filter is a signal demodulated from a carrier wave included in said high-frequency signal.

3. The wireless communication unit according to claim 1, wherein

said intermittent power supply part comprises a timer and, at a time specified by said timer, supplies power to said direct demodulation standby part.

4. The wireless communication unit according to claim 1, wherein

said high-frequency signal is a binary amplitude modulated, frequency modulated or phase modulated signal.

5. The wireless communication unit according to claim 1, wherein

when a plurality of said identification codes are included in said high-frequency signal and the plurality of said identification codes are listed,

transmission/reception is performed by relaying in turn to each of said wireless communication units corresponding to said listed identification codes.

6. A wireless network, wherein

the wireless communication unit according to claim 1 is disposed at a location at which communication with at least one adjacent other wireless communication unit is possible such that a plurality of wireless communication units are disposed in a net-like state,

a network management server for storing paths which enables communication between the mutually adjacent wireless communication units is provided, and

when one of said wireless communication units communicates with another one of said wireless communication units disposed in said wireless network, said network management server notifies the combination of said paths stored in said network management server.

7. A method of controlling power for a wireless communication unit performed in the wireless communication unit, which comprises:

a transmitting/receiving part for transmitting/receiving a high-frequency signal including an identification code for individually identifying the wireless communication unit; and

a direct demodulation standby part for prestoring an own unit identification code indicating said identification code of its own, and for demodulating said high-frequency signal to compare said identification code included in said high-frequency signal with said own unit identification code, wherein

when said direct demodulation standby part detects that said identification code coincides with said own unit identification code, power is supplied to said transmitting/receiving part, and

when said direct demodulation standby part detects that said identification code does not coincide with said own unit identification code, power is intermittently supplied to said direct demodulation standby part.