Patent ID: 8618956

Claim:
A method for detecting a moving vehicle within a predetermined area by means of at least a first wireless personal area network node device and a second wireless personal area network node device and a third wireless personal area network node device, wherein said moving vehicle carries a vehicle wireless personal area network node device, wherein said first wireless personal area network node device and said second wireless personal area network node device and said third wireless personal area network node device belong to one wireless personal area network, wherein said first wireless personal area network node device covers a first area and said second wireless personal area network node device covers a second area corresponding to said predetermined area and said third wireless personal area network node device covers a third area, said first and second and third areas being sized and located so that a vehicle to be detected enters said first area before entering said third area and before entering said second area, comprising the steps of: A) when entering said first area with said vehicle, said vehicle wireless personal area network node device discovers said wireless personal area network through said first wireless personal area network node device and prepares for joining said wireless personal area network through said third wireless personal area network node device, wherein said preparing comprises reducing a stand-by period of said vehicle wireless personal area network node device; B) when entering said third area with said vehicle, said vehicle wireless personal area network node device joins said wireless personal area network through said third wireless personal area network node device; C) when entering said second area with said vehicle, said vehicle wireless personal area network node device transmits information to said second wireless personal area network node device; and D) when leaving said wireless personal area network, said vehicle wireless personal area network node device leaves through said third wireless personal area network node device; wherein a transceiver of said vehicle wireless personal area network node device is continuously operative from starting step B until ending step D, whereby the detection of said moving vehicle within said predetermined area corresponds at least to the reception of said information by said second wireless personal area network node device.