A fully integrated broadband direct-conversion receiver for DBS applications

The key obstacle to successful integration of broadband receivers is that the wide-tuning range (C/sub H//C/sub L/>5) varactors required are not available in a standard process. In addition, when external hyper-abrupt varactors are used, a separate high-voltage supply (e.g. 30 V) is required to cover the entire frequency band. More recently, integrated wideband tuners have been reported using multiple wideband RC oscillators, but they require a complicated multi-loop architecture to achieve desired phase-noise performance. Using multiple integrated LC voltage-controlled oscillators (VCO) (including resonators) a fully-integrated single-loop frequency synthesizer is possible which allows the development of a single-chip solution for broadband applications. This results in a significant cost reduction and ease of system-board design.