Room: Florentine II
Organizer: Sule Ozer (ASU)
Moderator: Sule Ozer (ASU)

• Code-Modulated Embedded Test for Phased Arrays
  Kevin Greene, Vikas Chauhan, and Brian Floyd, NCSU

  Abstract: Millimeter wave (mm-wave) design has become the forefront for enabling multi-Gb/s wireless communications due to the abundance of available bandwidth at frequencies above 24 GHz. At these frequencies, phased arrays are used to meet link budgets by combining phase-adjusted responses of multiple antennas to form a high-gain, directive beam which is electrically steerable. Current requirements point to array sizes ranging from 8-32 elements, each of which must be measured and calibrated in terms of RF output power and phase to obtain the desired array performance. This paper will first review phased-array topologies and calibration requirements. We will then present a novel code modulated technique for manufacturing test of the array which uses only digital code modulators per element and a single global mm-wave squaring circuit in the form of a power detector. This approach allows measurement of full array performance with a single detector using minimum additional buit-in-test hardware. Behavioral models indicate that this method can estimate the phase response within 1 degree and an output power within 0.2 dB for each individual element using global array measurements.

• Post Fabrication Tuning of GaN Based RF Power Amplifiers for Pico Cell Applications
  Muhammad Ruhul Hasin, Jennifer Kitchen, ASU

  Abstract: The RF Power Amplifier (PA) is usually the bottleneck in designing high efficiency, high linearity wireless transceivers within any given power specification. Pico-cell basestation PAs deliver power in the range of 10 Watts, with aggressive gain and efficiency requirements for next generation cellular networks. The slightest variations in PA biasing or the input and output load networks can cause significant degradation in RF PA performance. This work discusses the impact of process variation and variability in input/output networks on RF performance, and suggests ways to regain various performance parameters through post fabrication tuning of the PA.

• Performance Enhancement Techniques and Verification Methods for Radio Frequency Circuits and Systems
  Hari Chauhan, Marvin Onabajo, Northeastern University

  Abstract: Nowadays, radio frequency (RF) circuits have to be optimized by design for reliable high performance with minimal power consumption to reach complete system-on-chip solutions that meet end user demands in diverse emerging applications. This paper reviews several recently developed design approaches and verification/simulation methods for performance improvements of RF integrated circuits. After the overview, the augmentation of an RF power amplifier with digital predistortion for enhanced linearity is discussed in more detail as an example.