Unused frequency band detection method and radio communication apparatus in cognitive radio system
US8594666B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Dec 7, 2009 |
| Grant date | Nov 26, 2013 |
| Priority date | — |
| Expiry date | Mar 18, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W64/00
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Provided is a technique that enables quicker detection of usable frequency bands in a cognitive radio system. Each radio communication apparatus in the system has, in common, a hash function used to obtain a frequency range from time information and location information. Each radio communication apparatus detects unused frequency bands while narrowing down a frequency range over which a detection process is performed by obtaining the terminal's own location information and current time information from GPS signals, and input them to the hash function. Since a transmitting node and a receiving node that perform a communication are at locations close to each other at the same time, they perform detection in the same frequency range. Therefore, an unused frequency band(s) that is usable by both of them can be detected. Furthermore, at different locations or at different times, the detection will be performed in different frequency ranges. Therefore efficient frequency utilization can be achieved. It is preferred that the nodes have a plurality of kinds of hash functions in common.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.