The 60GHz Tx RF pulse generator is the circuitry in the red box.

The function of this block is to generate a 60GHz mm-wave pulse from the multi-phase 10GHz LO signals and deliver this RF power to the integrated 50Ohm antenna load. There are 3 main circuit blocks : a NAND gate logic frequency synthesizer to combine/synthesize the 60GHz pulse from the 12 multi-phase shifted 10GHz signals, a pre-amplifier chain to amplifier the output of the NAND gates and buffer to the input of PA, and a PA stage to drive the antenna load.

Below plot shows how the 60Ghz is generated from 6 phase-shifted pulses at the input of the NAND gates. The 6 pulses are practically ORed together by the effect of the shared resistor load of the NAND gates.

The output 60Ghz signal and the intermediate stage amplitude are shown in the following plot:

The final swing at antenna load is quite small, which means the power is not efficiently delivered to ANT load. We need to look deeper into this issue...

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