Digital IF and Digital Modem Options
RT Logic is leading the way in the emerging field of satellite ground network architectures employing Digital IF front-ends and IP-Modems. Typically in modems or radios today, the Analog-to-Digital conversion is collocated with the DSP functions of the receiver. Digital IF technology allows a customer to conduct the analog-to-digital converter (ADC) very close to the antenna and then package the ADC samples into Digital IF packets. Using COTS network devices and standard IP packets, the ADC samples can be transferred to modems across the building or around the world without the negative effects of from cable loss or distortions.
RT Logic has implemented systems for NASA programs using both of the leading standard formats for digitized IF data over IP networks: VITA-49 and Signal Data Distribution Standard (SDDS). Algorithms for these efforts support both narrowband and wideband data. We are also active in supporting the United States (US) Army’s Open Standards Digital Interface (OSDI) development group for establishment of using VITA-49 in the next generation all digital ground station architectures.
RT Logic products cover both ends of the architecture – digitization of RF bandwidth into samples contained in industry-standard IP packets, and the demodulation and/or remodulation of those samples in the IPmodem which can be local to the Digital IF front end or remotely located on the other side of the world.