Wideband base station receiver with analog-digital conversion based on RF pulse width modulation

This paper presents a novel wideband receiver architecture for base stations. In contrast to existing systems, the analog-digital conversion is done directly in the radio frequency domain and is based on pulse width modulation. Measurements with a 5MHz LTE signal received at carrier frequencies varying between 900MHz and 2350MHz confirm the frequency flexibility of this concept. The captured spectrum of a WCDMA signal with 80MHz bandwidth demonstrates the possible detection of broadband signals. In addition, the capability of supporting instantaneous reception of non-contiguous frequency bands is proven by successfully detecting two signals with carrier frequencies of 900MHz and 2350MHz.

I. Introduction

Data rates in mobile communication systems are increasing faster than ever due to growing user capacity and demands on newer technologies and applications. As a result, next generation base stations have to cope with complex modulation schemes and large signal bandwidths while at the same time supporting different signal standards and multiple frequency bands. These requirements are accompanied by the need for reduction of power consumption in mobile communication systems.