Spectral Monitoring and Signal Intelligence

Regulation of the radio frequency spectrum is accomplished through a process called spectrum monitoring. Spectrum monitoring provides users, regulators and intelligence groups with valuable information as to how the spectrum is being utilized. From a regulatory perspective, spectrum monitoring ensures that spectrum users are adhering to local regulations and licensing parameters in an attempt to minimize interference amongst users of the spectrum. Communication providers or users of the spectrum may perform monitoring tasks to ensure proper operation of their systems or to troubleshoot interference problems affecting them. Finally, spectrum monitoring provides valuable information to intelligence bodies, looking to characterize the radio frequency environment and gather information to support their various missions.

Background on Spectrum or Spectral Monitoring and Signal Intelligence

Generally when performing spectrum monitoring, there are several important characteristics of the hardware platform that must be considered to ensure success in the task. The most flexible solutions utilize fast tuning, wide instantaneous bandwidth and broad frequency coverage with software providing the ability to capture the data. These solutions provide users with the capability to monitor large segments of the radio spectrum allowing them to gather vast amounts of information as quickly as possible. The speed of the receiver affects the user’s ability to capture transient or short duration events. The faster the receiver, the more likely the user will capture the information they need, without having to spend a great deal of time monitoring the spectrum. Receiver sensitivity is critical in that, the more sensitive a receiver is, it will allow the user to identify lower level signals, which may either be located far away from the receiver, or simply from a low power transmitter. The use of software for the collection of data is critical in providing the user with the ability to post process the data. Depending on the monitoring application, it may be advantageous to perform unattended monitoring or remote spectral monitoring. In these cases, the data can be logged and reviewed at the user’s convenience, providing a higher level of analysis capability than simply viewing live data. Once data is logged, it may be saved and used for future comparison, a task which is not possible with just a receiver. Automation and collection of data in the monitoring process provides a higher level of capability to the receiver, allowing monitoring personnel to be more efficient and successful in their tasks.

Summitek Instruments Oasis Spectrum Monitoring and Interference Analysis Software

OASIS provides an off-the-shelf spectral analysis solution for NI PXI-5660 users. OASIS requires no software development. OASIS extends the capabilities of the NI PXI-5660 by allowing the user to view multiple frequency ranges simultaneously, or in the case of multiple instances of the NI PXI-5660, remotely control the instruments under one user interface.

With the increasing number of transmitters coming on the air, interference is becoming more prevalent in the wireless community. Wireless service providers have used spectrum analyzers to monitor their channels/frequencies and the adjacent spectrum as well as try and find sources of interference. Unfortunately, the best a spectrum analyzer can do is display the interfering signal to the user; leaving the user to determine the source of the interference. Understanding the RF environment, knowing which transmitters are operating nearby as well as identifying any new or unlicensed emitters is a significant step in reducing the time required to solve interference problems. In addition to solving interference problems, OASIS provides intelligence organizations with tools that can utilized to quickly characterize the RF environment, collect and store data and provide unattended or remote operation.

OASIS has an extensive set of tools to automatically characterize the RF environment and compare the actual environment to a database of known emitters. OASIS can construct a database by monitoring the local RF environment or an optional database of FCC licensed emitters is available in the United States. OASIS users simply enter which frequencies are being affected by interference and then OASIS can generate a listing of only those suspect emitters in the area that can generate interference. OASIS uses the NI PXI-5660 to test the suspects. OASIS reduces the amount of time spent in the field and provides reports that can be used to prove interference.

Users can now leverage the NI PXI-5660 and OASIS to provide data to support spectrum management processes through archival storage of data, unattended and remote operation, and post-processing of data. Also, OASIS helps ensure compliance with spectrum regulations, for it quickly identifies licenses and unlicensed emitters and tracks non-compliant transmitters with emission masks and limits. Finally, OASIS has helped numerous customers ensure quality of service and network reliability by providing an easy, economical means for identifying sources of interference, direction finding of rogue emitters, and managing efficiency of spectral usage from channel occupancy statistics.

Oasis Screenshots

[+] Enlarge Image
Figure 1: Summitek Instruments Oasis Spectrum Monitoring Software


[+] Enlarge Image
Figure 2: Summitek Instruments Oasis Software


[+] Enlarge Image
Figure 3: Multi-Window Reporting


Figure 4: 3D Report

Advantages of NI PXI-5660 and Oasis Software

• Off the shelf solution for the NI PXI-5660. No software development required.
• Record and view multiple frequency bands on a single NI PXI-5660 which enables quicker resolution of problems.
• Deploy and control multiple NI PXI-5660s in the same space as a bench top spectrum analyzer.
• Perform unattended data logging for hours, days or weeks for later analysis which reduces time spent in the field.
• Remotely monitor test locations and change test scenarios over an Ethernet connection which saves time and money traveling to and from test locations.
• Measurement capabilities common to a bench top spectrum analyzer with an economical platform using modular, flexible, software-defined COTS hardware.
• The complete hardware and software solution is more economical than most bench top spectrum analyzers alone.
• National Instruments provides advanced signal processing and demodulation toolkits which can be used with the NI PXI-5660.

  Resources and Links
  

1. Summitek Instruments Website
2. Oasis Spectrum Monitoring and Interference Analysis Product Page
3. Oasis Brochure

Reader Comments | Submit a comment »