Spectrum Issues that Impact Intelligent Transportation Systems

The following are spectrum and/or wireless communications issues that have the potential to impact ITS, and therefore have en of interest to the ITS Joint Program Office at USDOT. They are listed in the approximate order of the band of interest. Underlined issues are of critical importance; other issues are indirectly related to the program.

VHF

• Highway Advisory Radio – currently used in various, "low-tech" forms by state Departments of Transportation to convey traffic and travel information
• High speed data FM subcarrier – the NAB is conducting field trials in support of a national standard, which is expected to support wide-area metropolitan data needs of ITS navigation and other systems; one of the three proponent systems under consideration was developed with DOT funding
• Other subcarriers – Additional testing is being done with low-speed FM (RBDS) and AM

220 MHz

• FHWA has been assigned 5 narrowband frequency pairs on a nationwide basis – these will support nationwide compatibility of ITS by providing universal channels for advisory, "hailing", and other applications; testing is underway

Cellular telephony

• Wireless E911 – implementation of this service will greatly facilitate deployment of the Emergency Notification and Personal Security user service; comments have been submitted by ITS America and DOT during this rulemaking process
• Position and location monitoring using the CMRS (cellular) system – being tested to determine the potential to support ITS positioning requirements

902928 MHz

• DSRC protocols – the Department is facilitating meetings among current vendors and users of DSRC in the LMS band to try to achieve industry consensus on nationwide compatibility of protocols and operating procedures, in anticipation of future spectrum opportunities. DOT does not necessarily advocate longterm use of this band for DSRC due to increasing congestion and unlicensed use

58505925 MHz

• DSRC – a new spectrum allocation is being sought by ITS America to allow proliferation of all envisioned ITS user services that utilize DSRC; FHWA intends to use the May 1996 Certification of Spectrum Support (Stage 2) to experiment with applications in the meantime

11, 23, 31 GHz

• Wireless communication for traffic surveillance and signal control – Recent reallocation of the 31GHz band to the new LMDS service will result in displacement of certain secondary users who operate point-to-point microwave links for traffic signal control; DOT filed comments in this proceeding and advises the field on developments

4777 GHz

• Collision Avoidance Radar – the automotive industry has pursued allocations successfully for these services on their own, with support from DOT. Cooperative R&D between industry and DOT/NHTSA on these systems has been ongoing for some years.

Public Safety

DOT and ITS America participated heavily in the recent Public Safety Wireless Advisory Committee (PSWAC) process – comments were filed in the subsequent FCC request for comment; PSWAC recommended the 5850 MHz band for DSRC services that could be made available to public safety agencies.

There are a number of navigation policy issues of interest to ITS, namely:

• Potential expansion of public DGPS capability – could provide navigation systems with further levels of accuracy; not typically needed by existing services, but of possible value to public safety agencies that rely on accurate positioning to respond to certain incidents; possibilities are currently being assessed
• GPS "Next Generation" (L5 frequency) – offers similar potential; ITS user requirements should be considered and the ITS JPO has been a party to these discussions among USDOT and DoD
• Federal Radionavigation Plan – The ITS JPO participates in this biennial USDOT – DoD effort to ensure that requirements analysis accounts for surface transportation users

In addition, there are a number of wireline telecommunications issues of interest to ITS, namely:

• Resource sharing of highway rights-of-way with communications service providers
• Development of national and international communications standards and protocols
• Establishment of an N-1-1 number to support travel/transportation information
• Open Video Systems and other new services that could support traffic management surveillance needs, or otherwise impact sharing of gov't and nongov't comm resources
• Other Telecommunications Act provisions/implications