Compact Size Multi-Channel True Time Delay Moudle with High Accuracy

A 9-bit digital true time delay (TDD) and amplification module with high integration is proposed in this paper. The true time delay units, bi-directional amplifiers, serial-to-parallel converter and power pulse modulated circuits are integrated in a multi-chip module (MCM) with monolithic microwave integrated circuit (MMIC) and surface mount technology (SMT). Multi-layer microwave board is used to implement the routing of DC, control and RF signals. Moreover, in order to achieve better flatness of time delay, distributed amplifiers and high isolation cavity structures have been adopted. To calculate the spatial isolation of the cavity structures, electromagnetic simulation with microwave high frequency software has been utilized. For verification, a multichannel TDD module has been designed, fabricated and measured. According to the measured results, the TDD module achieves the receive gain within 4.5 dB ± 0.8 dB, transmit power within 17dBm ± 1.0 dB, and high time-delay accuracy within ± 0.5 ps for 6.25 ps and ± 20 ps for 1600 ps, simultaneously.