{'fraction_non_alphanumeric': 0.04964539007092199, 'fraction_numerical': 0.019700551615445233, 'mean_word_length': 4.7207207207207205, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Imaging performance analysis of a FOPEN UWB random noise radar

Ultra-wideband (UWB) radar has proven to be a very powerful tool for underground and obscured object detection and identification. The combination of using low frequencies, such as VHF and UHF bands or even lower, and using UWB waveforms creates a wide variety of applications (see Davis, M.E. et al., 1999). The UWB waveforms can be linear FM (LFM), step-frequency, random noise, and so on. Among these, random noise waveform would be a desirable choice. The transmission of a UWB random noise waveform provides additional advantages in preserving covertness while ensuring extremely fine range resolution. The University of Nebraska has developed and field tested a 250-500 MHz foliage penetration (FOPEN) radar which transmits and receives UWB random noise waveforms. The system design and some simulation results have been reported (see Xu, X. and Narayanan, R.M., Proc. IEEE AP-S International Symposium, vol.4, p.1956-59, 2000; Henning, J.A. et al., USNC/URSI National Radio Science Meeting, 2000). We give a system-level imaging performance analysis of the FOPEN UWB random noise radar (RNR) with comparisons to LFM/step-frequency radar (LFM/SFR). Preliminary field test results are also presented.