RADIO COMMUNICATION METHOD AND RADIO COMMUNICATION DEVICE

• US 20090262710A1
• Filed: 09/03/2007
• Published: 10/22/2009
• Est. Priority Date: 09/01/2006
• Status: Active Grant

• Current Assignee: Sovereign Peak Ventures, LLC (Dominion Harbor Enterprises, LLC)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Doi, Hiroshi, Matsumoto, Taisuke, Takahashi, Kazuaki
• Granted Patent: US 8,400,959 B2
• Time in Patent Office: Days
• US Class Current: 370/336
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Provided is a radio communication method capable of optimally using the wide-band communication enabled time while maintaining power saving in an ad hoc network. According to this method, in the ad hoc network using the wide-band communication and a narrow-band communication, transmission and output of the narrow-band synchronization tone signal and the resynchronization tone signal are controlled so that the reach radius of the narrow-band synchronization signal and the resynchronization tone signal exceeds the reach radius of the wide-band signal (milli-wave UWE signal). Thus, when radio communication devices pass by each other, super frame synchronization is completed before reaching the wide-band communication enabled range of the ad hoc network, thereby optimally using the wide-band communication-enabled time.

Claims

1. A wireless communication apparatus that carries out wideband communication with another wireless communication apparatus in an ad-hoc network, the wireless communication apparatus comprising:

a narrowband communication section that transmits and receives a narrowband synchronized signal for realizing superframe synchronization; and

a wideband communication section that transmits and receives a wideband data signal used in the wideband communication,

wherein the narrowband communication section transmits the narrowband synchronized signal in an output such that a signal reachable range of the narrowband synchronized signal is greater than a signal reachable range of the wideband data signal.

2. The wireless communication apparatus according to claim 1, further comprising:

a synchronizing section that acquires synchronization with another superframe group when the narrowband synchronized signal is received from the another wireless communication apparatus; and

a probe signal transmitting section that transmits a probe signal for detecting the another wireless communication apparatus when the synchronization with the another superframe group is acquired.

3. The wireless communication apparatus according to claim 2, wherein the probe signal transmitting section transmits the probe signal such that a signal reachable range of the probe signal is equal to the signal reachable range of the wideband data signal.

4. The wireless communication apparatus according to claim 1, wherein the narrowband communication section transmits the narrowband synchronized signal such that the signal reachable radius R of the narrowband synchronized signal satisfies R=r+vNT, where T is a superframe period, N is a resynchronization superframe lap count, v is a moving speed of the wireless communication apparatus and r is the signal reachable radius of the wideband data signal.

5. The wireless communication apparatus according to claim 1, wherein the narrowband synchronized signal and the probe signal comprise unmodulated tone signals.

6. The wireless communication apparatus according to claim 3, wherein:

the narrowband synchronized signal is comprised of a synchronization tone signal for synchronization control and a resynchronization tone signal for resynchronization;

the probe tone signal is comprised of a probe tone signal for probing a neighboring wireless communication terminal and an FX probe tone signal for probing a wireless communication terminal to swap files with; and

the synchronization tone signal, the resynchronization tone signal, the probe tone signal and the FX probe tone signal are each configured with a duration of a tone signal and an intermittent pattern.

7. The wireless communication apparatus according to claim 4, wherein:

the FX probe tone signal is configured by, when a predetermined period passes, transmitting a tone signal comprising a first duration after the synchronization tone signal is transmitted;

the probe tone signal is configured by, when the predetermined period passes, transmitting a tone signal comprising a second duration longer than the first duration after the synchronization tone signal is transmitted; and

the resynchronization tone signal is configured by, when the predetermined period passes, transmitting a tone signal comprising a third duration longer than the second duration after the synchronization tone signal is transmitted.

8. The wireless communication apparatus according to claim 1, further comprising:

a synchronizing section that acquires synchronization with another superframe group when the narrowband synchronized signal is received from the another wireless communication apparatus; and

a beacon period moving section that, when the synchronization with the another superframe group is acquired, moves a beacon period of a superframe group of the wireless communication apparatus to another offset position in a superframe after the synchronization.

9. The wireless communication apparatus according to claim 8, further comprising:

a detecting section that, if the movement to the offset position does not take place, detects whether or not there is an upper empty beacon slot in an original beacon period; and

a evacuating section that, if there is the upper empty beacon slot in the original beacon period, moves a beacon slot position of the wireless communication apparatus to the upper empty beacon slot.

10. The wireless communication apparatus according to claim 1, wherein:

the wideband communication section and the narrowband communication section further comprise an on-off keying modulator and demodulator shared between the wideband communication section and the narrowband communication section; and

the narrowband communication section transmits and receives the narrowband synchronized signal using a binary signal.

11. The wireless communication apparatus according to claim 1, wherein:

the wideband communication section and the narrowband communication section further comprise an on-off keying modulator and demodulator shared between the wideband communication section and the narrowband communication section; and

the narrowband communication section transmits and receives the narrowband synchronized signal using a signal spread by a predetermined spreading code.

12. A wireless communication method for carrying out wideband communication reciprocally between a plurality of wireless communication apparatuses in an ad-hoc network, the wireless communication method comprising:

transmitting a narrowband synchronized signal for realizing superframe synchronization; and

transmitting a wideband data signal used in the wideband communication,

wherein the narrowband synchronized signal is transmitted such that a signal reachable range of the narrowband synchronized signal is greater than a signal reachable range of the wideband data signal.