An 8-Channel Ku-Band Phased-Array Transmitter

An 8-channel CMOS phased-array transmitter in Ku-band is presented in this paper. In each channel, a 5-bit phase shifter and a 4-bit attenuator are integrated to control the output beams. The RMS phase error of the phase shifters is less than 3.2°, and the RMS amplitude error of the attenuator is less than 0.94 dB. The power gain for the single path including the power divider is 11.9 dB. The output referred P1dB reaches 13 dBm for each channel. Digital controller and temperature sensors are integrated. In order to be easily used in the large-scale phased array system, compact design is adopted to minimize the chip size. The chip is fabricated in standard 180 nm CMOS technology. The size of the whole chip is 8. 5x3 mm ² , and that of each channel is 3.8x0.5 mm ² .