Fig. 3: mmWave antenna array hardware design.

a, Physical layout of the backscatter modulator and 5 × 1-antenna array. b, mmWave backscatter communicator flexible prototype with an integrated pHEMT transistor front-end and patch antenna array.

a, Physical layout of the backscatter modulator and 5 × 1-antenna array. b, mmWave backscatter communicator flexible prototype with an integrated pHEMT transistor front-end and patch antenna array.