Demonstration of Adaptive Analogue Beam Forming in the E-Band

Abstract

In this paper, we report the test results of a small-scale prototype that implements an analogue-beam-formed phased antenna array in the E-band. A four-channel dual-conversion receive RF module for 71～76 GHz frequency band has been developed and integrated with a linear end-fire antenna array. Measured performance is very close to the simulated results. An ad-hoc wireless communication system has also been demonstrated. Low BER was measured for an 8PSK data stream at 1.5 Gbps with the receive array beam formed in the direction of arrival of the transmitted signal. To our knowledge this is the first steerable antenna array reported to date in the E-band.

Implementation of wideband digital beam forming in the E-band

“…Measured array gain was 9.5 dBi for steering angles below 11° and reduced to approximately 8.4 dBi at the steering angle of ± 35°. Obtained DBF results were in a very close agreement with those measured for the ABF array and EM simulation predictions [7] for steering angles within ± 40°. The magnitude and angle of the DBF and ABF main beam patterns were within 1 dB and 1 degree respectively.…”

“…Fig. 11 compares the Eplane co-polar array radiation patterns at 0° azimuth computed by the DBF and measured for the ABF [7]. In both experiments the calibration was performed at zero degree azimuth angle.…”

“…In both experiments the calibration was performed at zero degree azimuth angle. For the ABF [7], the array has been calibrated by cancelling the main beam to obtain a null at 0° azimuth. The null ABF calibration reference is also shown in Fig.…”

“…12 with the magnitude normalized to the maximum of the main beam at zero degree azimuth angle. Simulated at 0deg [7] ABF NULL refernce [7] Fig . 11.…”

“…For digital beam forming (DBF), each of the IF analogue signals was digitised and streamed to a PC for data processing and beam forming as shown in Fig. 2.. For analogue beam forming (ABF) [4,7], the phase and magnitude of each channel was controlled by 6-bit phase shifters and attenuators and a combined IF signal was de-modulated using a modem reported in [5]. This replaces the digitizer shown in Fig.…”