Performance evaluation of wavelength division multiplexing photonic analogue-to-digital converters for high-resolution radar systems
Cruz, P. E. D.
Alves , T. M. F.
optics and photonics journal Vol. 9, Nº 12, pp. 219 - 234, December, 2019.
ISSN (print): 2160-8881
Journal Impact Factor: (in )
Digital Object Identifier: 10.4236/opj.2019.912018
The performance of the wavelength division multiplexing (WDM) photonic ana-logue-to-digital converter (ADC) used for digitization of high-resolution radar sys-tems is evaluated numerically by using the peak signal-to-noise ratio (SNR) metric. Two different WDM photonic ADC architectures are considered for the digitization of radar signals with 5 GHz of bandwidth (spatial resolution of 3 cm), in order to pro-vide a comprehensive study of the compromises present when deploying radar sig-nals with high-resolution: i) a four-channel architecture with each channel employ-ing an ADC with 5 GSamples/s, and ii) an eight-channel architecture with each chan-nel employing an ADC with 2.5 GSamples/s. For peak powers of the pulsed source between 10 and 20 dBm and a distance between the radar antenna and the sensing object of 2.4 meters, peak SNR levels between 29 and 39 dB are achieved with the eight-channel architecture, which shows higher peak SNR levels when compared with the four-channel architecture. For the eight-channel architecture and for the same peak powers of the pulsed source, peak SNR levels between 11 and 16 dB are obtained when the distance increases to 13.5 meters. With this evaluation using the peak SNR, it is possible to assess the performance limits when choosing a specific radar range, while keeping the same resolution.