System and method for establishing relative distance and position of a transmitting antenna

A positioning method, applicable in a first device to determine a distance between a the first device and a second device, the first device comprising at least two receiving antennas, a number of the receiving antennas is defined as N, an angle between the directions in which adjacent two of the receiving antennas receive the strongest signals is 360°/N, the second device having a transceiving function, the positioning method comprising:

• (a) establishing a connection between the first device and the second device, obtaining a preset number of RSSIs of the receiving antenna, and
• using an average value of the RSSIs as the RSSI of the receiving antenna;
• (b) obtaining received signal strength indicators (RSSI) of the receiving antennas received signals from the second device;
• (c) determining which of the two receiving antennas is positioned closest to the second device according to received signal strength indicators (RSSI);
• and
• (d) obtaining an angle between the second device and the closest receiving antennas according to the received signal strength indicators (RSSI), and calculating a distance between the second device and the first device according to the angle and a gain of one of the closest receiving antennas.

A positioning system comprising:

• a first device comprising two receiving antennas, wherein a number of the at least two receiving antennas is defined as N;
• and
• a second device having a transceiving function, wherein the first device obtains received signal strength indicators (RSSI) of the receiving antennas, determines which of the two receiving antennas is closest to the second device according to the received signal strength indicators (RSSI), calculates an angle between the second device and the closest receiving antennas according to the received signal strength indicators (RSSI), and obtains a distance between the second device and the first device according to the angle,
• wherein N is equal to four, an angle between the directions of the strongest received signals between adjacent receiving antennas is 90°, the first device calculates the angle between the second device and the closest receiving antennas according to a formula as follows:
• θ
• ⁢
• 1
• =
• 1
• 2
• ⁢
• cos
• -
• 1
• (
• 1
• In
• (
• AntI
• RSSI
• -
• AntIV
• RSSI
• 10
• )
• +
• 1
• -
• 1
• )
• ,
• wherein, θ1 represents the angle between the second device and the closest receiving antennas, AntIRSSI and AntIVRSSI represents RSSIs of the two closest receiving antennas.