As many sleek new wire- less phones loaded with attractive features find their way under the tree this year, TIA committees already are working on next-generation standards. Consumers are becoming used to calling number identification and short message service (SMS), which increasingly are provided with digital phone packages, but the marketing and engineering folks are not done yet. There is no such thing as too many features, and competition is not just between carriers, but between the PCS and cellular industry segments and between digital technologies. Analog even offers occasional bursts of innovation.

Competitive Breakout TIA standards committees reflect the competitive alignment, based on the troika of radio technologies. TR-45.1 defines analog standards (including N-AMPS and the analog compatibility mode used by both TDMA and CDMA); TR-45.3 defines TDMA standards (IS-54 and IS-136); and TR-45.5 defines CDMA standards (IS-95). You can bet that if TR-45.5 comes up with a cool idea, TR-45.3 will have its own version no later than the next revision (and vice versa).

CDMA Standards TIA standards subcommittee TR-45.5 is balloting its next-generation CDMA standard as ANSI standard TIA/EIA-95-B. It will support calling name presentation. When roaming, CDMA phones will be able to indicate the type of roaming partner (from "premium" with the best roaming arrangements, down to "available" for the least-desirable roaming arrangements). Plus, the system will be able to redirect the phone to the best available system. Data will be supported at speeds up to 64kb/s.

Even the government should be happy with the priority access and channel assignment (PACA) feature, which will allow priority users to have first call on idle channels during times of severe overload. PACA also can be used to give 911 calls priority over regular calls.

For wireless local loop, CDMA will emulate the capabilities of a copper loop (such as different ringing styles and meter pulses for billing). A similar feature, applicable to CDMA mobile uses, is to emulate the duration and other parameters of DTMF tones better to ensure access to services that are fussy about such things.

CDMA is revamping its identifiers. International mobile station identity (IMSI) will be separated fully from the MIN to enhance international roaming. The mobile directory number also will be separated from the MIN (although its only use in a phone is for display purposes) to improve support for wireless local number portability.

TDMA Standards The TDMA elves also have been busy. TIA standards subcommittee TR-45.3 has been working on an ANSI standard that will be called TIA/EIA-136 Revision 0 (not to be confused with interim standard TIA/EIA/IS-136 Revision 0).

TDMA services come with better acronyms than CDMA. Take TSAR, for example -- not the Russian royalty, but teleservice segmentation and Reassembly -- which will allow longer short messages to be delivered to a mobile. The current limit for both TDMA and CDMA is just above 200 characters due to SS7 network limitations. The standard will allow longer messages by breaking the message up into pieces that are smaller than 200 characters (segmentation) and gluing them back together in the mobile (reassembly).

Generic UDP transport service (GUTS) will allow arbitrary Internet protocols (and therefore, applications) to be extended to a mobile phone. A new international roaming enhancement, "+" code dialing, will allow international roamers to bypass the local international access prefix ("011" in North America). They can press a "+" key before the international number. So, +1-403-555-1212 would work in Hong Kong, Mexico or even at the North Pole.

Some features are being developed for both digital technologies (although the acronyms usually are different). Both the TDMA and CDMA camps, for example, are enhancing SMS to allow one radio message to carry the same short message simultaneously to all mobiles, within the broadcasting cell site, that have the capability of receiving it or to a subset of mobiles (based on the category of message). This capability may be used to extend the emergency alert system that currently can broadcast over radio and TV stations in the event of a hurricane, earthquake or unidentified flying reindeer.

Analog Standards Analog is further behind in the development of new services but is not completely left out. The latest version of the analog standards EIA/TIA-553-A and TIA/EIA/IS-91-A will support sleep mode, which will extend the battery life of analog phones. The plans for the next generation of standards (EIA/TIA-553-B and TIA/EIA/IS-91-B) include IMSI to improve support for international roaming.

One of the biggest problems that standards engineers face is backward-compatibility. Digital system control-channel structures are newer and more flexible, allowing older mobiles to ignore messaging that supports new features. This still means that new features that require radio interface modifications are unlikely to be available to people with older phones, which makes features that can be implemented with network modifications more attractive when carriers want existing subscribers to purchase the service. You side-step the problem if the new service is bundled with a phone or is intended to stimulate phone sales. For example, the AT&T Digital One Rate plan requires a dual-band TDMA phone, which ensures that customers on this plan will use AT&T spectrum if it is available in the roaming service area and, therefore, minimizes the roaming charges that AT&T must absorb.

Analog has a bigger problem with compatibility, which partly explains the shorter list of new features. The analog control channel has to be compatible with existing AMPS, N-AMPS, CDMA and TDMA phones (which all use this control channel when operating in analog mode), some of which did not implement the forward-compatibility provisions of older standards correctly and thus have trouble when modifications to the control channel are introduced. Carriers also are less enthusiastic about implementing new analog features because digital is being used as a way to differentiate their services. Enhancing analog would provide their competition with new services as well as themselves.