Abstract: The present disclosure provides a gated range scanning linear frequency modulated continuous wave (LFMCW) radar structure, including: a frequency synthesizer, a first mixer, a second mixer, a first filter, and a third mixer. The frequency synthesizer is configured for generating a first local oscillating signal and a second local oscillating signal, a frequency of the first local oscillating signal varying in a frequency range, each frequency corresponding to a sub-range of a coverage range scanned by the LFMCW radar structure. The first mixer is configured for mixing a copy of a transmitted signal and the first local oscillating signal to generate a first output signal (the receiver's first local oscillator). The second mixer is configured for mixing the first output signal and a received signal from a receiving antenna to generate a second output signal that includes an intermediate frequency (IF) signal being received by the first filter.

Abstract: In accordance with various embodiments, a method for uplink multiple accessing based on code division multiple access (CDMA) technology and a related system are provided. The method comprises: designing a practical uplink spreading waveform for a code division multiple access (CDMA) based SCN by leveraging a plurality of pseudorandom sequences and investigating a channel coding block and a modulation block for the CDMA based SCN; determining an uplink frequency sub-band division for the CDMA based SCN to optimize a tradeoff between a performance and an implementation cost of CDMA based SCN; and specifying a configuration of a control system of the CDMA based SCN.

Abstract: A systematic interferences mitigation design for protected satellite communications (SATCOM) is provided. An advanced channel coding is designed to provide coding gain for SATCOM even in the presence of synchronization errors due to the effect of radio frequency interferences (RFIs). A unified SATCOM system spectrum efficiency and energy efficiency method is developed with a unified interference model for SATCOM dynamic resource allocation (DRA). The SATCOM system DRA is designed with a game theoretic engine and optimizations providing traffic control, power control, and modulation and coding agile waveform adaptations. The interferences mitigation design is implemented with software defined radio USRP and GNU-radio to maintain communication link quality of services (QoS).

Abstract: In accordance with various embodiments, a method for uplink multiple accessing based on code division multiple access (CDMA) technology and a related system are provided. The method comprises: designing a practical uplink spreading waveform for a code division multiple access (CDMA) based SCN by leveraging a plurality of pseudorandom sequences and investigating a channel coding block and a modulation block for the CDMA based SCN; determining an uplink frequency sub-band division for the CDMA based SCN to optimize a tradeoff between a performance and an implementation cost of CDMA based SCN; and specifying a configuration of a control system of the CDMA based SCN.