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2ndRF

The six members of 2ndRF at the 2017 Senior Design Expo.

Thank you to our sponsors, the National Telecommunications and Information Administration (NTIA) and the Institute of Telecommunication Sciences (ITS)!

The frequency spectrum allocation required by the Federal Government is rapidly becoming congested. In order for continued optimization of the frequency spectrum, monitoring of proper use is necessary. Currently the spectrum is statically assigned into frequency bands; this results in portions of the spectrum being unused, while other portions are overcrowded. The final objective of NTIA is to redistribute frequencies that can be better utilized in the spectrum.

The Little Brother Sensor, a spectrum monitoring system, is sponsored by the National Telecommunications and Information Administration (NTIA), and more specifically the Institute of Telecommunication Sciences (ITS). The Little Brother Sensor is an RF sensor which consists of an analog receiver front end, a software defined radio, and a control unit. The system is self-calibrating every hour to ensure that the information being collected is valid. The Fast Fourier Transform (FFT) and I/Q data that it receives in a data file is converted into a Javascript Object Notation (JSON) format and sent to the Measured Spectrum Occupancy Database (MSOD) via TCP/IP Ethernet, which will run on a separate computer. The Little Brother Sensor will not do further processing on the sent data, that task is being passed off to another product. The Little Brother Sensor continuously monitors the 698 MHz to 809 MHz and 3.55 to 3.70 GHz frequency bands and routinely sends reports of readings to an ITS database. This database is used to determine portions of the spectrum that are overused, underused, or being improperly used.

NTIA, specifically ITS, is the primary benefactor of the Little Brother Sensor. ITS is a research laboratory for NTIA which studies how the frequency spectrum can be more efficiently used. Other product beneficiaries include entities in the government, such as the military and the Federal Communications Commission (FCC),Ìý as well as commercial entities such as cell phone service providers or internet service providers. However, anyone using the spectrum benefits from the product; it has the potential to allow for spectrum sharing instead of the fixed -allocation system that is currently emplaced by the FCC.

This system will allow for scanning and characterization of the 700 MHz and 3.5 GHz frequency bands so that man-made noise (MMN) sources and unlicensed transmitters can be detected. Once these signals are detected, the system will report this activity to the database, which ITS can use to determine rouge signals. Currently, this can only be done using high end equipment, which is very expensive and requires months of data collection. The system will leverage Software Defined Radio (SDR) technology and a printed circuit board receiver (PCB) to create a low cost solution.