GPS for orientation navigation , timing & frequency calibration

GPS for orientation navigation , timing & frequency calibration

?High-precision measurement

12V DC power supply

One single-frequency active antenna

Orientation principle and application of GPS

Basic orientation principle of GPS: the satellite uninterruptedly sends its own ephemeris parameters and time information; after users receive this information, the three-dimensional position, 3D direction and velocity and time information are obtained through calculation.?

GPS can be used for orientation navigation, timing and frequency calibration, high-precision measurement, intelligent transportation systems, vehicle monitoring & dispatching system.

Composition of GPS system

GPS consists of three independent components:

1) Space: more than 24 working satellites and three backup satellites.

2) Ground Support System: a master control station, three injection stations and five monitoring stations.

3) User equipments: it can receive the transmit signal of GPS satellite to obtain the necessary navigation and orientation information. After data processing, navigation and orientation will be completed. The hardware of GPS receives in general consists of the host, antenna and power supply. What we are now using are the equipments of customers.

Example of GPS satellite synchronizing device – TIME NAV time service navigation receiver

TIME NAV time service navigation receiver is the accessory matching with K30 series Testers, and used for multiple test instruments to output the synchronous test in the long distance.

Receiver is directly connected to the test instrument through RS-232 standard serial port.

Outer structure diagram of TIME NAV time service navigation receiver

Data Interface

10 KHz square wave and 1PPS sec pulse is output from 4-pin signal port, the definition is as follows:

? 1-10 KHz square wave output port, 2-1PPS sec pulse output port, 3-hold, and 4-ground?

??? 3.? Data Connection

It is used for the connection of data input and output. The male terminal is connected with COM1 interface of the receiver and the female terminal is connected with the serial interface of the computer, which is the standard RS-232 interface, DB9-pin connector, the connection diagram is as follows:

It is used for the connection of differential data input. The male terminal is connected with COM2 interface of the receiver and the female terminal is connected with the differential range receiver or TV set and other equipments, which is the standard RS-232 interface, DB9-pin connector, the connection diagram is as follows

4. Antenna

One single-frequency (L1=1575.42MHz) active antenna of GPS is used for the receiver.

5. Power supply

12V DC power supply is connected exteriorly.

?Notices

When GPS receiver is running, it receives and decodes low-power radio signals transmitted by the satellite. If other radio equipments or electronic devices is used near GPS receiver, as may produce electromagnetic interference (EMI), impacting the receiver and decoder on work. In such circumstance, the interference can be reduced or eliminated only through closing the source of interference or removing GPS receiver.

If no data are output from the receiver, firstly check whether the receiver and the antenna port are linked closely; check whether the antenna is overhead in the open spaces (TIMENAV), only if the receiver must receive three or more satellites, it can output data and display orientation information); the antenna should be also enabled far away from the glass wall and water surface and other substances with good reflectivity to ensure the accuracy of data. Secondly, check whether the data line and the receiver ports, PC ports are connected correctly and closely and whether the power supply is normal, and ensure that the baud rates of LABMON50 and the receiver are consistent and that the data formats of the receiver and LABMON50 software are consistent and ensure that. The communication Parameter Setup of LABMON50 software is correct.