A Power-Scalable Channel-Adaptive Wireless Receiver Based on Built-In Orthogonally Tunable LNA

Abstract

Most of the traditional RF circuits are static or minimally tunable using some digital controllability. For example, high power, low power and shut down modes are available in some commercially available transceivers. If available, the tuning knobs affect different specifications in an interdependent manner, resulting in changing several specifications when only one needs to be tuned. This is not enough for power optimal operation of complete self-aware self-adaptive circuits and systems. Independent or orthogonal tunability of the important conflicting specifications using built-in tuning knobs allow optimal adaptation of the wire-less systems. In this paper we demonstrate the design and benefits of orthogonal tuning knobs using an inductorless LNA as a test vehicle. The design of an orthogonally tunable LNA is discussed that has a 14 dB Gain tuning range and 30 dB OIP3 tuning range as its power consumption goes down by 20×. Measurement results on this LNA validate the concept of orthogonal tunability. Use of this orthogonally tunable LNA within an adaptive wireless receiver framework shows power savings of 2× compared to a static system and an extra savings of 22% compared to a traditional nonorthogonal adaptive system.