Digital Two-Way Radios Address Interoperability Dilemma

Federal agencies that use two-way land mobile radio (LMR) systems, once commonly known as "walkie-talkies," are under a mandate by the Federal Communications Commission (FCC). Based on the mandate, federal agencies must migrate to new digital equipment by 2005. In turn, a growing number of state and local agencies are expected to follow suit in the near future.

Digital technology will enable greater spectrum efficiency, making room for more radio users with less interference between users and channels.

These advantages are likewise required by the public-safety radio technical standard, known as APCO Project 25 (or P25 for short), accepted by the FCC as compliant with its mandate. The Association of Public-Safety Communications Officials - International, Inc. (APCO) is the world's oldest and largest nonprofit professional organization dedicated to the enhancement of public-safety communications. APCO Project 25 is a joint effort of U.S. federal, state, and local governments, with support from the U.S.

Telecommunications Industry Association (TIA). State government is represented by the National Association of State Telecommunications Directors (NASTD) and local government by APCO.

The P25 standard adds other requirements and distinct advantages that are also expected to draw a wide range of government users at state and local levels, as well. That fundamental requirement is interoperability.

The term interoperability has two different yet complementary meanings. Interoperability among radios compliant with the P25 standard will enable communications among different agencies (as well as communications within the same agency, as usual).

In addition, the interoperability requirement means that any manufacturer's equipment in compliance with the APCO Project 25 specifications must also operate in harmony with other manufacturers' products in compliance with the standard. All P25-compliant radios must be able to communicate with each other on assigned frequencies and channels.

For agencies purchasing new digital radios, the interoperability of LMR equipment compliant with P25 can be a critical

factor. APCO Project 25 levels the playing field among manufacturers, while opening the door to competition for public-safety and other government agency contracts under tight budgets. Goals are to ensure interoperability among any manufacturers' products compliant with the standard. As a result, purchasers can make choices based on features and prices, knowing that any selection of products compliant with P25 will provide basic interoperability.

Competitive Solutions

Decisions surrounding radio purchases may be guided by certain factors. Some are indeed critical, while others may be equalized or at least moderated in accordance with the P25 standard.

Many concerns play a role in evaluating P25. For example, manufacturers invariably claim special unique features and benefits of their own products, supposedly separating

To comply with P25 requirements, a manufacturer's digital products must be backwardas well as forwardcompatible. In other words, current P25-compliant equipment must be compatible with older equipment that complies with the standards. Therefore, current models cannot make older models obsolete.-Future upgrades, enhancements,and new models introduced must also be compatible with today's P25-compliant equipment. Based on the compatibility standards, today's investment in P25 equipment will not be made

durability, reliability, ease of use, ease of programming, audio quality, and long battery life.

Upon the digital platform, a host of enhancements and increased functionality will essentially be driven by software, rather than hardware, in the months and years ahead.

With P25, the foundation is now in place and expected to drive wider acceptance among government agency users across the board. What is most important has already arrived: the P25 standard. In effect, P25 interoperability is the base line for forward-looking, digital twoway radio communications.

What remains for further consideration? All things being relatively equal in regard to functional interoperability among the products of competing manufacturers, what are the differences in cost? Price comparisons can often cast the deciding vote on which product to buy.

By adopting P25 as a basic standard of performance, purchasers can take a close look at existing LMR capabilities, as well as plan a reasonable, cost-effective approach to meeting the 2005 deadline for migration to spectrum-efficient digital radio systems. P25 assures performance to the highest standard, while opening the market to increase competition and drive down prices.

them from all the rest of their competitors. This claim correlates to our nation's right to free speech.

In contrast, when dealing with radio interoperability, all manufacturers' products that are P25 compliant must share a certain commonality of function. While products may be different, in essence they must all be the same in being able to communicate with each other, one brand to another. Choice of which brand to purchase still remains an important option, however. Future choices will also be an option, as interoperability means not being locked into one supplier in years ahead.

Companies that have developed proprietary technology in full compliance with all APCO Project 25 specifications attest to the benefits of P25. If any manufacturer's products meet P25 specs, they are considered to be high-quality, high-performance radios. Because P25 has proven to be an extremely rigorous standard in the public safety and homeland security arena, meeting the specs is similar to receiving an official seal of approval.

In addition, if one federal agency approves and purchases a manufacturer's products with proprietary or licensed technology, thus recognized as complying with P25, then those products are automatically pre-approved for purchase by any other federal agency. Throughout the LMR industry, P25-compliant radios are increasingly becoming the lead product line of name-brand radio manufacturers.

Today's investment in P25 equipment will not be made obsolete by future improvements.

obsolete by future improvements. These systems are meant to be used day after day, year after year, while functioning at the same level of interoperability with newer equipment in the years ahead. The P25 standard ensures that initial investment.

Comparison Shopping

Based on real-world user requirements, purchasers should evaluate features and options of interoperable radios on a practical basis. Are specific features necessary, critical, and essential, or are they bells and whistles? Beyond all of the performance specs established by P25, and all the associated features that are not unique, purchasers should assess the differentiating factors and their importance for specific needs.

Public-safety radios are designed for use in extremely hazardous emergencies, and these factors may also serve to define principle characteristics of interest and importance to all users. Factors include

Editor's Note: David Storey is President and CEO of RELM Wireless Corporation, a manufacturer of landmobile radios, based in Melbourne, FL.

PRO PATHWAYS

—Association of Public-Safety Communications Officials --International, Inc. (APCO). Visit: www. apcointl.org/frequency/project25/.

—RELM Wireless Corporation. Visit: www.relm.com.

—Telecommunications Industry Association (TIA). Visit: www.tia online.org/standards/project_25/.