A transponder is a type of network device that reconstructs incoming electronic, wireless, or optical signals. With physical media like Ethernet or Wi-Fi, data transmission can only span a limited range before the signal degrades. Realize physical layer connection, amplify, reshape or regenerate the attenuated signal, which plays a role in extending the distance of the network segment.

Buying conditions, the GPS module SiRFStarIII accepts the data of each output position, usually the data in $GPRMC reduced data format, including latitude, longitude, speed (knot), movement direction angle, year, Month, hour, minute, second, millisecond, positioning data is valid or invalid, and other important information. The statement format is as follows: $GPRMC,,,,,,,,,,,,,*,HH.

Extended information

The transponder receiving antenna receives the signal from the ground station. After preamplification and frequency conversion, the intermediate frequency digital signal is demodulated and judged, and Perform data processing. In order to resist interference, error correction coding can also be performed on the satellite. The processed signal is digitally modulated, frequency converted and power amplified by the transmitting part, and then forwarded to the ground station.

In digital satellite communication systems, the use of processing transponders can eliminate the accumulation of noise, so the transmit power of the transponder can be reduced while ensuring the same communication quality;

Secondly, different modulation methods can be selected for the uplink and downlink lines to obtain the best transmission; in addition, various other processing can be performed on the baseband signal in the processing transponder to meet various needs and enable on-board digital switching. become possible.

Baidu Encyclopedia-Transponder