A 100-element HBT grid amplifier

Moonil Kim, Emilio A. Sovero, Jonathan B. Hacker, Michael P. De Lisio, Jung Chih Chiao, Shi Jie Li, David R. Gagnon, James J. Rosenberg, David B. Rutledge

Research output: Chapter in Book/Report/Conference proceedingChapter


A l00-element 10-GHz grid amplifier has been developed. The active devices in the grid are chips with heterojunction-bipolar-transistor (HBT) differential-pairs. The metal grid pattern was empirically designed to provide effective coupling between the HBT’s and free space. Two independent measurements, one with focusing lenses, the other without, were used to characterize the grid. In each case, the peak gain was 10 dB at 10 GHz with a 3-dB bandwidth of 1 GHz. The input and output return loss were better than 15 dB at 10 GHz. The maximum output power was 450 mW, and the minimum noise figure was 7 dB. By varying the bias, a signal could be amplitude modulated with a modulation index as large as 0.65. Tests show that the grid was quite tolerant of failures—the output power dropped by only 1 dB when 10% of the inputs were detuned, The grid amplifier is a multi-mode device that amplifies beams of different shapes and angles. Beams with incidence angles up to 30° were amplified with less than a 3-dB drop in gain.

Original languageEnglish
Title of host publicationActive Antennas and Quasi-Optical Arrays
PublisherJohn Wiley and Sons Inc.
Number of pages11
ISBN (Electronic)9780470544068
ISBN (Print)0780334868, 9780780334861
Publication statusPublished - 2009 Jan 1
Externally publishedYes


  • Gain
  • Gain measurement
  • Heterojunction bipolar transistors
  • Lenses
  • Oscillators
  • Power amplifiers
  • Strips

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)


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