GIRD Systems, Inc. (GIRD), proposes application of non-maximally decimated (NMD) filter banks (FBs) as the basis of a second generation spectrum scanning and notching solution for the MUOS waveform. NMDFBs are flexible to design and provide a simple design methodology for perfect reconstruction (PR), which is an essential characteristic of a FB in the notch filtering application. Through previous experience with the MUOS waveform from the Information Repository (IR) on a previous SBIR program with the Navy, particularly the spectrum scanning and notch filtering approaches, GIRD anticipates that the novel application of NMDFBs will enable delivery of a second generation algorithm that improves frequency resolution (
Benefit: It is anticipated that the proposed filter banks will provide improved notch frequency resolution, notch depth, computational cost and design flexibility. Spectral scanning for detection of interference finds application in many interference mitigation solutions and can be used to focus spectral searches in SIGINT receivers. Digital notch filters find application to interference as well, particularly narrowband interference to wideband signals of interest. As such the filter bank approach to notch filtering, given its efficiency when implemented in polyphase form, can be applied to many commercial systems, including wifi, 4G LTE, and 5G NR systems.
Keywords: spectrum scanning, spectrum scanning, Notch Filter, mDFT, MUOS, perfect reconstruction, Channelizer, Filter Bank, FFT
