Transponders form a vital part of the ground segment for satellite-borne SAR. Normally placed on flat, low clutter terrain, these devices offer absolute calibration of the SAR image. They provide a point target of sufficient accuracy for end to end radiometric calibration of satellite SAR instrument obtained data.

Antenna Wireless SAPARC-L calibrators provide a simultaneous recording and
constant RCS mode which provides significant improvements over its competitor
technologies in this field.

These L-Band Transponders (1.27GHz) uses a 48-inch horn antenna and a 25-inch
Orthomode Transducer in order to provide a radiometric echo equivalent of about
60dBm², the magnitude of which is an industry pioneer in itself.

Typical Specifications for our SAPARC-L units are as follows:

o Dual Operation Mode:
- Airplane SAR (PiSAR)
- Satellite (PALSAR/ALOS)
o Bandwidth: 100MHz ± 10MHz (centered on 1.27GHz)
o RCS: 10-60dBm² in steps of 1dBm²
o Cross-pol isolation: min. 29dB
o 3dB Beamwidth: 10° ± 2°
o Short-term stability: < 0.1dB / 2 hours
o Transmit peak power: 29dBm ± 1dBm
o Receiver Noise Figure: 2.0dB ± 0.2dB
o Battery operation time: 2.5 hours min. (with fully charged battery)
o Temperature range: -10° to 50° C
o Humidity range: 35 to 100RH
o Monitor transmission peak power and temperature
o Measure azimuth antenna patterns
o Data downloading via a serial port to a laptop
o Data recording initiated by the presence of SAR pulses
o Calculation of absolute RCS
o Microprocessor controlled RCS
o LED for received signal indication