Was Advanced Mobile Phone Service Amps An Open Standard?

Avant-garde Mobile Phone Organisation (AMPS)

AMPS facts

Analog FM modulation
RF bandwidth thirty kHz. The band can accommodate 832 duplex channels, among which 21 are reserved for call setup, and the residuum for voice communication.
Frequency allocated by FCC on 824-849 MHz for downlink and 869-894 MHz for uplink traffic.
Uses the same system throughout the US
Bachelor in U.Due south., Canada, Hong Kong, New Zealand, Thailand
A narrowband versus exists with a 10 kHz channel spacing, such that 2496 channels tin can be assigned, in stead of 832 for the normal AMPS way.

Digitization of AMPS

The uniformity of the analogue AMPS organization throughout the US highly contributed to its success of capturing 2/three of the analog cellular subscribers worldwide. Effectually 1995, AMPS had an estimated xiii Million subscribers in the U.S.. US manufacturers and operators take been divided about the operational merits of various technologically advanced options for radio channel access and digital modulation, in particular the choice between Code Segmentation Multiple Access (CDMA) and Fourth dimension Division Multiple Access (TDMA) transmission formats for cellular telephony. For the migration towards all-digital operation, the objective of the Federal Communication Commission (FCC) has been to introduce a digital system that was fully compatible with the existing analog AMPS system, i.e., the FCC was looking for a new arrangement that uses the same radio spectrum as the old analog system, but at least ten times more efficient in spectrum use. By 1988, the Cellular Telecommunications Industry Clan (CTIA) divers a full set up of User Functioning Requirements (UPR).

Two different solutions have come up. The states cellular network operators are implementing a narrowband TDMA version of AMPS, known as IS-54. Meanwhile, the Californian company Qualcomm promotes a CDMA concept, presenting scientific and experimental evidence to academic fora virtually the technical superiority of CDMA over TDMA. Experimental CDMA systems are in operation in several cities, based on the IS-95 standard. Expectations are that AMPS product shipments reached its top in 1996 with Motorola, Nokia, NEC and Ericsson dominating the market place. Digital systems including PCS are expected to become toll effective with analog AMPS in the fourth dimension frame 1997-2000.

PCS: AMPS 1900

A 1900 MHz version of AMPS has been developed, which allows dual-band/dual-fashion 800/1900 MHz systems. It allows operators to provide identical PCS applications and services in both bands. Seamless inter-working between 800 and 1900 MHz networks is possible through dual-band/dualmode mobile stations. Subscribers on a D-AMPS 1900 channel can handoff both to/from a D-AMPS aqueduct on 800 MHz too every bit to/from an analog AMPS channel.

Existing 800 MHz D-AMPS operators can employ the 1900 MHz spectrum to increase capacity and develop new user segments in their 800 MHz networks. For example, 800 MHz cells tin can provide wide-surface area coverage (through macro-cells) and act as umbrellas for 1900 MHz micro- and picocells. The small cells can embrace the indoor role environment, shopping malls, airports and hot spot coverage. The umbrella cells would carry the signals for fast-moving subscribers and fill in gaps in between 2 isolated microcells.

D-AMPS 1900 mobile phones will be marketed initially in single-band 1900 MHz as well every bit dual-band 800/1900 MHz versions. In the long run, dual-band versions may prove themselves able to replace single-band versions at both 800 and 1900 MHz.

AMPS Network Layout

The D-AMPS 800/1900 organization architecture is like to most other cellular system architectures (e.g. GSM network architecture). Information technology contains a Switching Arrangement, an Operation and Support System, base stations and mobile station.

The switching organisation

The Switching Organization contains v chief functional entities:

The Mobile Switching Center (MSC) performs the telephony switching functions for the network. It controls calls to and from other telephone and data communications networks such as Public Switched Telephone Networks (PSTN), Integrated Services Digital Networks (ISDN), Public Land Mobile Networks (PLMN) and Public Data Networks.
The Company Location Register (VLR) database contains all temporary subscriber data needed by the MSC to serve visiting subscribers who are temporarily in the area of the MSC.
The Dwelling house Location Register (HLR) database stores and manages user subscriptions. It contains all permanent subscriber information including the their service profile, location information and activeness status.
The Authentication Heart (Ac) supports authentication and encryption functionality. It verifies the user's identity (by authitication) and ensures the confidentiality of each call (by encryption) . This protects network operators confronting fraud.
The Message Center (MC) supports messaging services.

The base station

The Base Station is the radio equipment needed to serve each prison cell in the network. 1 base station site may serve more than i cell.

The Operation and Support System

The Functioning and Support System supports operation and maintenance activities in the network to allow for reliable and cost-efficient operation.

The mobile station

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