Gain, Noise Figure and Bandwidth-Limited Dynamic Range of a Low-Biased External Modulation Link

Abstract

We present a broad-bandwidth (1 -12 GHz) low-biased external modulation fiber-optic link without preamplifiers that has a gain of 6 dB-14 dB and a noise figure of < 7.S dB everywhere in this broad bandwidth, with a record low noise figure of only 3.4 dB at 2 GHz. The third-order distortion-limited spurious-free dynamic range (SFDK) of this link within any suboctavc portion of the 1-12 GHz range of operating frequencies is approximately 120 dBHz <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2/3</sup> in a 1-Hz instantaneous receiver bandwidth. We describe the high-performance components in this link and discuss the extent to which their performance varies with frequency, and show which of these components' frequency-dependent parameters affect which of the three figures of merit (gain, noise figure, and SFDR).