Handheld Interference Monitoring
Detection System (HIMDS)

System Description

The HIMDS provides the FAA with a small handheld short-range general purpose DF receiver system that can precisely locate interference to its final location. For direction finding in the GPS band it must be within clear radio line-of-sight. At lower frequencies it can locate a specific source of emission through foliage, buildings, etc. It has an effective range of approximately 1 mile at surface level. There are approximately 302 units in the field. These units are K95-100 series general purpose scanning receivers tunable to all GPS frequencies. The units used a set of different antennas for the spectrum band of interest. 150 units will be GPS capable by end of FY01 with the addition of an L-Band log periodic antenna. These units are widely dispersed across the National Airspace System (NAS) and Airways Facilities field specialists are trained to react quickly to RFI incidents affecting the NAS using the HIMDS.

Production/Delivery Status:

Currently the plan is to acquire 150 L-Band Log Periodic antennas during 2001 and provide them as an add-on antenna to 50% of units in service. The remaining 50% are planned to be outfitted during 2002.

All K95-100 series handheld DF units are procured by the Systems Management Office (SMO) sending Airways Facilities Specialists to the FAA Academy RFI training school. Add-on L-Band log periodic antennas are being procured.