Graphical Approach for Evaluating Performance Limitations in Externally Modulated Analog Photonic Links
ABSTRACT We present a novel graphical approach for evaluating the performance of analog photonic links employing an external intensity modulator biased at quadrature. A single graph is sufficient to grasp the engineering tradeoffs among noise figure, third-order spurious-free dynamic range, and RF gain for various values of half-wave voltage and dc photocurrent.
- SourceAvailable from: dtic.mil[show abstract] [hide abstract]
ABSTRACT: Radio-frequency (RF) photonics provides increased or previously unavailable capabilities for many military platforms and applications. As compared to electronic approaches, photonics offers increased transmission distances in antenna-remoting applications, unrivaled bandwidth in signal-processing and other electromagnetic-warfare applications, and decreased size and weight in numerous military platforms. In addition, fiber optics as a transmission medium offers invulnerability to electromagnetic interference and near-complete electrical isolation. We describe advances in the theoretical understanding of analog-photonic systems made at NRL in 2007, along with the accompanying record-setting performance demonstrated in our experiments. We have applied our expertise to the design and implementation of two state-of-the-art prototype systems for military antenna-remoting and electromagnetic-warfare applications. Each of these prototypes and their significance are described below.
- [show abstract] [hide abstract]
ABSTRACT: In this work, we present a photonically enabled built-in-test (BIT) architecture for electronic support measures (ESM) systems. The BIT system employs an analog optical link in concert with a dipole probe antenna and wireless link to provide ~10.5 GHz test signals to the ESM receiver. This work details the optical link design and provides a characterization of the link gain as a function of received photocurrent and photodiode bias. In addition, we describe and characterize the wireless link in terms of the ESM antenna pattern and probe position and polarization. The design of the probe antenna and integrated balun are discussed and gain calibration are provided. In this work we also provide initial measurements of the impact of the BIT system on receiving operations by measuring the antenna patterns (azimuth and elevation) of the biconical antenna under test. We also discuss extension of the photonic BIT architecture to wideband (500 MHz - 40 GHz) operation.06/2009;
Conference Proceeding: Long-haul analog links tutorial[show abstract] [hide abstract]
ABSTRACT: Presents a collection of slides covering the following topics: analog versus digital fibre optics; applications of long-haul RF photonics; components and IMDD metrics; single channel fibre effects; alternate modulation format; transmitter linearization techniques; and photodiode nonlinearities.Optical Fiber Communication (OFC), collocated National Fiber Optic Engineers Conference, 2010 Conference on (OFC/NFOEC); 01/2010