Abstract
A band-pass limiting filter (BPLF) based on a microstrip comb line
loaded with PIN diodes is proposed in this letter. In contrast to
conventional comb line filter designs, the BPLF utilizes PIN diodes to
replace capacitor components. When the power of the input signal is
below a certain level, the proposed BPLF acts as a filter. While for an
input signal whose power is above a certain level, it behaves like a
limiter. According to measurement data, the proposed BPLF has a broad
passband with an insertion loss of about 3.5 dB from 8.2GHz to 9.0GHz,
and a low limiting level of less than 17dBm with a high power input of
50W (47dBm). In general, the proposed BPLF enables dual selectivity of
frequency and power, and can be applied to the front end of RF channels.