Phase noise cancellation performance in self-heterodyning transceivers for wireless backhaul applications

Abstract

This paper presents a novel system architecture for small cell base stations with integrated millimeter-wave wireless backhaul. In contrast to existing systems, the data signal on the wireless backhaul uses the same 3GPP compliant signal than on the access link serving the users. The small cell omits the 60GHz local oscillator source completely by using the self-heterodyning mixing approach and transmits only a suppressed carrier. Measurements of a single-carrier WCDMA signal on a simplified setup with lower carrier frequency demonstrated that due to successful phase noise cancellation the 3GPP ACLR and EVM requirements are easily met, even with 15dB dynamic on the backhaul link. Moreover, the required broadband capability is proven using an LTE signal with 20MHz bandwidth.Index Terms -Millimeter-wave, phase noise cancellation, self-heterodyne mixing, small cells, wireless backhaul.978-1-4799-5507-7/15/$31.00

Cross-Mixing Hybrid Beamformer for Wideband Apertures

“…This implies that half of the used power holds no information. For this reason, other designs [22] use a low power carrier signal that is separately amplified at the receiver via a power amplifier. Alternatively, a frequency locking scheme [23]- [25] can be employed at the receiver to lock its frequency to the carrier.…”

“…Also, our proposed design removes phase-locked loops [28] to significantly reduce hardware requirements and improve stability. Notably, similarly to [22], the new design employs low noise amplifiers (LNAs) to amplify the signals from the oppositely placed antenna elements to achieve the best Using the presented CMB, a sub-array beamforming can be realized, as depicted in Fig. 3.…”