Electrically Small Antennas' Design Criteria and Measurement Challenges

The contrast between the design criteria for electrically small transmit and receive antennas is studied in this work. On the transmit side, radiation efficiency (ohmic loss plus return loss) and data throughput are critical. However, a higher impedance mismatch on the receiving front end may reduce ohmic loss and expand the frequency bandwidth. So, a calculated mismatch can be added to improve the performance of the receiving ESA by lowering the overall noise figure and widening the frequency bandwidth. These contradictory design criteria suggest utilizing separate transmit and receive antennas to improve the transmitter and receiver performances.