Noise is a useful signal source for testing the performance of wireless components and products. In fact, it is the basis for the E911 Noise and Interference Generator from Noise Com (Parsippany, NJ), an instrument developed for testing the susceptibility to interference of E911 applications on cellular telephones, as well as GPS receivers used in airborne, automotive, defense and mobile locations. The test instrument is based on the company's digital noise, arbitrary waveform, and proprietary switching technology. The instrumentation-grade source can generate low-phase-noise interference from 800 to 2500 MHz. According to Noise Com's Vice President of New Business Development, Kent Wardley, "with the E911, we are addressing the many security issues facing the world today. Customers can use the same instrument to support a wide range of existing and emerging standard requirements to provide interference resistant location services."
The E911 Noise and Interference Generator is equipped with one or optionally two independent arbitrary waveform generators capable of 40-MHz bandwidth for interference generation over the L1 and L2 or L5 GPS bands. The instrument's integrated personal computer (PC) supports the generation of user-defined arbitrary interference and jamming waveforms, including pulses with 6.67-ns resolution and duty cycles from 0 to 100 percent. A Gaussian noise source provides a fixed low-level reference, which is used to calibrate the output power of the arbitrary waveform generator. An internal power meter ensures accurate measurements, assists in calibration and sets the accuracy of generated signals to +21 dBm.