Back in June 2004, land mobile radio manufacturer Icom filed a Petition for Rule Making, which the FCC finally put on Public Notice Jan. 27. Icom's petition seeks to re-allocate to the public-safety radio services the Part 22 Common Carrier channels in the 150 MHz band that were not purchased in two FCC auctions (Auction 40 and 48). (Full-disclosure notice: I prepared the petition on Icom's behalf and talked about it here when it was filed.)

The 150 MHz frequencies, allocated under Part 90 for public-safety services, are heavily utilized. Unfortunately, because these frequencies were not originally “paired,” the utilization is a mish-mash of mobiles and repeaters sharing channels, interfering with one another and failing to achieve the maximum channel utilization that otherwise might be achievable. Furthermore, the narrowbanding of the 150 MHz band yields 7.5 kHz channels, which require geographic separation between adjacent systems at this time.

In the 150 MHz band, there are 18 paired and four unpaired 25 kHz-wide frequencies allocated to the Part 22 Public Mobile Radio Services. These channels historically have been utilized for paging operation and, prior to the widespread growth of cellular telephone operation, were used for the provision of IMTS radio service.

The recent changes in the paging industry have resulted in a dramatic change in the utilization of these frequencies. Specifically, many of these 150 MHz paging frequencies now lay fallow, with previous licensees no longer licensed or removing their operation from the channels.

The commission conducted two auctions for geographic “overlay” licenses in the 150 MHz band (as well as other Part 22 bands) in Auctions 40 and 48. In Auction 40, more than 1750 economic area licenses for 150 MHz frequencies failed to generate a single bid. Thus, economic-area licenses for New York City, Miami, Atlanta, Cincinnati, Detroit, Milwaukee, New Orleans, Denver, Seattle and others were not bid upon.

In Auction 48, the commission re-auctioned those licenses for which no bids had been placed in Auction 40. After Auction 48, more than 900 licenses for 150 MHz spectrum still had no bidders. Economic-area licenses for paired channels that still remained unsold include Cincinnati (11 channel pairs unsold), Indianapolis (six pairs), Nashville (nine pairs) and Memphis (three pairs).

Icom surmised that if these channels could be reassigned to the public-safety radio services, it might provide capacity, as well as some “green space” to enable some sort of rechanneling of the Part 90 channels to create channel pairs. It also would minimize the need for the continued waivers that public-safety agencies have been filing to use more Part 22 channels, at least in the 150 MHz band.

Of course, existing operations in the band should be grandfathered. But Icom's petition also represents another possibility for auction winners to cooperate with public-safety agencies to bring even further capacity for systems, as was done in South Dakota. In this manner, the Virginia statewide 150 MHz public-safety system might have sufficient capacity for the system's complete buildout.

Let's assume that a public-safety agency is presently using five awkwardly paired 150 MHz Part 90 frequencies. If this agency were to obtain two contiguous Part 22 channels, the agency could have seven 6.25 kHz narrowband channels without exceeding the maximum channel bandwidth. Utilizing Icom's or Kenwood's new narrowband equipment, which is backward-compatible to traditional wideband radio systems (operating on a narrowband channel in narrowband mode and in analog wideband mode in the presence of those systems), the agency could have a 12-channel trunked radio system.

However, such scenarios won't happen without your support. If you think that this is a good idea, please let the FCC know.

Alan Tilles is counsel to numerous entities in the private radio and Internet industries. He is a partner in the law firm of Shulman Rogers Gandal Pordy & Ecker and can be reached at