Deliverable 8.4: Report on the optimized front-end, including electrical, calibration, mechanical and manufacturing

As part of Work Package 8 of the EISCAT_3D Preparatory Phase project a low noise amplifier for the proposed antenna array has been being developed at Luleå University of Technology. The system is expected to operate at approximately 235 MHz with a transmission bandwidth of 5 MHz and a reception bandwidth of 30 MHz. As the sky noise temperature at this frequency range is in the order of 140 K, the aim is for an LNA noise temperature in the order of 30 K. In order to minimise transfer function variations the return loss of the amplifiers should be high (preferably larger than 20 dB).

EISCAT_3D low noise amplifier

An LNA subsystem suitable for the EISCAT_3D system was designed and verified, with performance well in line with requirements. As a part of this work a number of low-noise transistors have been characterised for VHF operation and device variation statistics for the most promising device has also been collected.