The personal communication systems and networks (PCS/PCN) are locationindependent communication systems. They allow freedom of communication for any type of information between any two points. The locales of end-entities can be indoor/outdoor, in a mobile unit, rural areas with sparse population, crowded metropolitan areas, in an aeroplane or at sea.
The end-entities can be at a stand-still or be moving at jet-speed. The separation between the end-entities could be arbitrary. PCS/PCN is an emerging global system with international connectivity. A standing committee on ITU, namely the World Administrative Radio Conference (WARC) co-ordinates the Future Public Land Mobile Telecommunication (FPLMTS) systems so as to develop a global system of PCS/PCN for aggressive deployment in the coming years.
Some of the challenging aspects of the associated efforts are as follows:
- Judicious use of available EM spectrum
- Choosing appropriate technology by taking into account of spectrum scarcity
- Poising the usage demands and services to be offered.
TDMA techniques, together with SS methods and CDMA strategies, are targeted for use in PCS implementations. For example, in order to enhance the traffic capacity of PCS, digital multiple access methods such as time-division duplexed TDMA (TDD-TDMA), frequency-division duplexed TDMA (FDD-TDMA), slow frequency-hopped TDMA/CDMA etc. are being considered.
The general framework criterion towards PCS implementation is to render the system interconnected and internetworked so that the users are free of wirleline tether (tetherless) and/or cord (cordless). PCS should enable voice as well as fax and computer data transfers on a personal basis across an exhaustive internetwork of terrestrial (wireline and/or wireless) and satellite links with global coverage.
Further, multiuser outdoor radio-ports would permit the users in a building to get access to remote end-entities. Likewise, an indoor radio-port would interconnect the users within a building. Thus, regardless of the locale of a person and the type of end-entity, communication is to be facilitated in the envisioned global PCS.
Eventually, adjunct to telephone service, PCS will include end-entities comprised of mobile personal computers − the laptop/palmtop version, handhelds, subnotebooks, and personal assistants (personal organiser plus pager and cellular telephone.)
Personal communication network (PCN) is a concept that includes a single identifying number with an individual subscriber. That is, each person will have a personal ID number (PIN), eliminating the need for separate home or work numbers. Any traffic intended for an individual reaches that person regardless of the location (of that person), rather reaching that user’s (home or work) number.
That is, the user can receive telecommunication services over a wide geographical area and the service is almost mobility-independent. The user is just expected to carry an operational wireless communication device throughout roaming. Unlike cellular systems, the PCN is designed to operate independently as well as interface with the standard wireline network.
It is designated to operate in the 1.9 GHz band. Relevant radios are intended to be very small and the transmitted power is kept low. This warrants more cell-site deployment. Hence, PCNs are known as microcellular systems.
