A 10-Bit 10 GSPS Optical ADC for Radar Signal Processing
Abstract
Next generation radar systems for tactical aircraft will need to improve aircraft survivability, allow for cooperative multistatic mode of operation, provide efficient anti-jamming features, and compensate for motion-induced clutter. Faster digital processors are required, in particular analog-to-digital converters (ADCs) for digital processing of X-band radar systems. This effort investigated and demonstrated an optoelectronic scheme for a high-speed optical ADC. The system was designed with the following objectives in mind: a) maintain the RF signal in the electrical domain throughout the conversion process and eliminate use of bulky optical components; b) low optical power budget (e.g. basic sampling circuit requires 50-60 m optical power); c) direct interface to electronic quantization circuits; and d) compact design. The effort achieved sampling rates of 4 GSPS. The limitation in conversion speed was dictated by the photodiode which had a 3dB-bandwidth of 5GHz. The following tasks were completed: 1) Pspice simulation of sampling circuit; 2) Design implementation and synchronization of the optical clocks needed for a) sampling of incoming RF signals, b) demultiplexing the sampled signals to lower data rate for electronic quantization; 3) Interface of optical sampling circuit with National Instrument LABVIEW data acquisition system for quantization of sampled signals to produce an 8-bit gray code digital output; and 4) Optical sampling circuit optimization resulting in a 50% reduction in optical power consumption.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 2003
- Accession Number
- ADA419738
Entities
People
- Eric Donkor
Organizations
- University of Connecticut