1-Bit Wideband Reconfigurable Transmitarray Unit Cell Based on PIN Diodes in Ku-Band

In this letter, a 1-bit wideband reconfigurable unit cell for transmitarray applications in Ku-band is proposed. The unit cell consists of a Vivaldi structure (transmitting), a phase shifter, and a microstrip Yagi structure (receiving). Based on the current reversal mechanism, a pair of reverse mounted PIN diodes was introduced to obtain the required phase resolution (two phase states: 0° and 180°). The unit cell is fabricated and measured using a specific waveguide simulator. The measured minimum insertion losses are 1.58 and 1.61 dB for State I and II, respectively. The insertion loss is less than 2.58 dB (1 dB bandwidth) from 14.88 to 17.28 GHz for State I, and less than 2.61 dB (1 dB bandwidth) from 14.73 to 17.25 GHz for State II. The 1 dB bandwidth of the unit cell is about 15%. The measured phase difference remains 180°, and the maximum error is only 3.8°.