Navigation system and navigation method
The navigation system includes a plurality of first signal sources and a mobile terminal, each of the plurality of first signal sources is configured to transmit a first wireless signal; the mobile terminal is configured to receive the first wireless signal, determine a position of the mobile terminal according to the received first wireless signal, and determine a route from the position of the mobile terminal to a target first signal source to perform navigation, according to an electronic map, the received first wireless signal, the position of the mobile terminal, and the target first signal source.
1. A navigation system, comprising:
a plurality of first signal sources, each of the plurality of first signal sources being configured to transmit a first wireless signal;
a mobile terminal, configured to receive the first wireless signal, determine a position of the mobile terminal according to the received first wireless signal, and determine a route from the position of the mobile terminal to a target first signal source to perform navigation, according to an electronic map, the received first wireless signal, the position of the mobile terminal, and the target first signal source,
wherein the mobile terminal is further configured to: acquire information of all of the first signal sources which face a camera through the camera of the mobile terminal, after the determining the position of the mobile terminal and before the determining the route; and select a target first signal source according to the information of all of the first signal sources which is acquired.
2. The navigation system according to claim 1 , wherein the first wireless signal includes a position information of the first signal source and a power information of the first wireless signal.
3. The navigation system according to claim 2 , wherein the first signal source transmits the first wireless signal at a predetermined time interval, and the first wireless signal further includes an ID of the first signal source.
4. The navigation system according to claim 3 , wherein the position information of each of the first signal sources B i in the plurality of first signal sources is denoted by coordinates (x i , y i , z i ) of the first signal sources B i in a preset spatial rectangular coordinate system; where, i is an integer greater than or equal to 1 and less than or equal to I, and I is a total number of the first signal sources corresponding to the first wireless signals received by the mobile terminal;
the mobile terminal is configured to:
determine a distance R i between the first signal source B i and the mobile terminal according to a signal strength of the first wireless signal of the first signal source B i which is received;
determine position coordinates (x 01 , y 01 , z 01 ) of the mobile terminal in the preset spatial rectangular coordinate system according to the determined distance R i and the coordinates (x i , y i , z i ) of the first signal source B i by using a formula below:
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determine the position of the mobile terminal according to the determined position coordinates (x 01 , y 01 , z 01 ) and the electronic map.
5. The navigation system according to claim 4 , wherein the mobile terminal determines the distance R i between the first signal source B i and the mobile terminal by using a formula below:
RSSI i =−[(10nlgR i )+ A ];
wherein RSSI i represents signal strength of the first wireless signal received by the mobile terminal, n represents an environmental parameter, and A represents signal strength received at 1 m from the first signal source.
6. The navigation system according to claim 1 , further comprising: at least one second wireless signal source,
wherein the second wireless signal source transmits a second wireless signal,
the mobile terminal further receives the second wireless signal transmitted by the second wireless signal source, determines an initial position of the mobile terminal according to the received second wireless signal; and determines a route from the initial position to a target region to perform navigation, according to the electronic map, the target region including the target first signal source and the determined initial position.
7. The navigation system according to claim 6 , wherein the first wireless signal transmitted by the first signal source received by the mobile terminal is: a first wireless signal transmitted by a first signal source located in the target region and within a range of a first preset distance from the mobile terminal.
8. The navigation system according to claim 6 , wherein the second wireless signal includes a position information of the second wireless signal source and a power information of the second wireless signal.
9. The navigation system according to claim 6 , wherein there are a plurality of second wireless signal sources,
3 second wireless signals among the plurality of second wireless signals received by the mobile terminal are selected, and a position of a second wireless signal source Y k corresponding to the selected second wireless signal is denoted by coordinates (x k , y k , z k ) of the second wireless signal source Y k in a preset spatial rectangular coordinate system; where, k is an integer greater than or equal to 1 and less than or equal to 3;
the mobile terminal is configured to:
determine a distance R k between the second wireless signal source Y k and the mobile terminal, according to received signal strength RSSI k of the second wireless signal source Y k by using a formula below:
RSSI k =−[(10nlgR k )+ A ];
where, n represents an environmental parameter, and A represents signal strength received at a distance of 1 m from the second wireless signal source;
determine an initial position (x 02 , y 02 , z 02 ) of the mobile terminal according to the received coordinates (x k , y k , z k ) of the second wireless signal source Y k , by using a formula below:
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10. The navigation system according to claim 7 , wherein the mobile terminal is configured to display a real-life picture of an environment where the target first signal source is located when being located within a range of a second preset distance from the target first signal source, and the second preset distance range is less than or equal to the first preset distance range.
11. The navigation system according to claim 1 , wherein the mobile terminal determines a direction of the mobile terminal according to a geomagnetic sensor and an acceleration sensor; acquires the information of all of the first signal sources which face the camera through the camera, after the camera of the mobile terminal is turned on; and selects the target first signal source according to the information of all of the first signal sources which is acquired.
12. A navigation method of the navigation system according to claim 1 , comprising:
receiving a first wireless signal transmitted by a first signal source;
determining a position of a mobile terminal according to the received first wireless signal;
determining a navigation route for navigation according to an electronic map, the received first wireless signal, the position of the mobile terminal, and a target first signal source,
wherein the first wireless signal includes a position information of the first signal source and a power information of the first wireless signal,
wherein the determining the position of a mobile terminal includes:
determining a distance R i between the first signal source B i and the mobile terminal according to a signal strength of the first signal source B i which is received, which includes:
determining a distance R i between each of the first signal sources B i and the mobile terminal by using a formula below;
RSSI i =−[(10nlgR i )+ A ];
where RSSI i represents signal strength of the first wireless signal received by the mobile terminal, n represents an environmental parameter, and A represents signal strength received at a distance of 1 m from the first signal source,
wherein the navigation method further comprises: determining A in the formula, including:
allowing a distance between the first signal source and the mobile terminal to be 1 m, controlling the first signal source to transmit a signal of a fixed power, acquiring an RSSI 0 value of signal strength received by the mobile terminal;
repeating the above-described step to acquire a plurality of RSSI 0 values, acquiring a plurality of A 0 values according to a formula RSSI 0 =−[(10nlgR 0 )+A 0 ];
calculating an average value of the plurality of A 0 values acquired, and determining the average value as the A value.
13. The navigation method according to claim 12 , wherein the first signal source transmits the first wireless signal at a predetermined time interval, and the first wireless signal further includes an ID of the first signal source.
14. The navigation method according to claim 13 , wherein the position information of the first signal source B i is denoted by coordinates (x i , y i , z i ) of the first signal source B i in a preset spatial rectangular coordinate system; where, i is an integer greater than or equal to 1 and less than or equal to I, and I is a total number of the first signal sources corresponding to the first wireless signals received by the mobile terminal;
the determining the position of a mobile terminal includes:
determining position coordinates (x 01 , y 01 , z 01 ) of the mobile terminal in the preset spatial rectangular coordinate system according to the determined distance R i and the coordinates (x i , y i , z i ) of the first signal source B i by using a formula below:
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determining the position of the mobile terminal according to the determined position coordinates (x 01 , y 01 , z 01 ) and the electronic map.
15. The navigation method according to claim 12 , further comprising:
correcting the A value, including:
allowing the distance between the first signal source and the mobile terminal to be a plurality of test values from 2 m to 10 m, controlling the first signal source to transmit a signal of a fixed power, acquiring an RSSI value of signal strength received by the mobile terminal;
determining a distance value according to the RSSI value and a formula RSSI k =−[(10nlgR k )+A];
comparing the distance value obtained by calculating with the test value, and if a difference between the distance value and the test value is greater than 10% of the distance value, executing a step below:
allowing the distance between the first signal source and the mobile terminal to be 1 m, controlling the first signal source to transmit a signal of a fixed power, acquiring an RSSI 0 value of signal strength received by the mobile terminal,
repeating the above-described step to acquire a plurality of RSSI 0 values, acquiring a plurality of A 0 values according to a formula RSSI 0 =−[(10nlgR 0 )+A 0 ];
calculating an average value of the plurality of A 0 values obtained; and determining the average value as the A value; and
continuing until the difference between the distance value and the test value is less than or equal to 10% of the distance value.
16. The navigation method according to claim 12 , further comprising:
displaying a real-life picture of an environment where the target first signal source is located, when navigating to located within a range of a second preset distance from the target first signal source; and navigating to a position where the target first signal source is located according to the displayed real-life picture.