15-02-2013, 12:11 PM
corDECT
[attachment=51021]
ABSTRACT
The traditional wired local loop used to connect each telephone subscriber to the nearest exchange is expensive and unreliable. Wireless Local Loop (WLL) systems largely eliminate these copper wires using wireless technologies and could provide a cost effective solution. corDECT is one such WLL system, based on the DECT (Digital Enhanced Cordless Telecommunications) standard, that provides toll-quality voice and data capability at a cost below that of a wired local loop. Using micro-cells and Dynamic Channel Selection (DCS), it can handle high subscriber densities without frequency planning. corDECT is gaining commercial acceptance in India and a number of other countries.Using a simple Queueing Network Model (QNM), we find that the 1,000-line corDECT system could achieve a Busy Hour Call Attempt (BHCA) of 36,000 calls/hour, which is far greater than its requirement of 20,000 calls/hour. We show how the system could be expanded to a 10,000-line exchange with a BHCA of over 2,10,000 calls/hour. We also investigate the feasibility of implementing 64 kbps data service along with voice. It is shown that this requires modest hardware improvements.
INTRODUCTION
Traditionally, a pair of copper wires is used to connect each telephone subscriber to the nearest exchange. Such a wired local loop poses the following problems [6]:
_ The laying and maintenance of copper cable up to the subscriber’s premises incurs high cost. Also, this cost is increasing with time as the cost of copper increases.
_ The per-line cost for rural areas is significantly higher due to the large amount of cabling infrastructure required to take even a few telephone lines to remote villages.
_ Most faults are in the local loop, due to water-logging, damage or theft of cables.
_ Rapid deployment is difficult owing to the regulatory and other problems in laying buried cables.
ADVANTAGES AND LIMITATIONS
Voice Quality
corDECT delivers the same toll-quality speech performance as a good copper-based local loop..
Data Services
The employment of 32 kbps ADPCM permits all voice-band data services available from a conventional wired connection. It is also possible to occupy a double time slot on air to transmit at 64 kbps with error correction.
Internet Access Speed
Internet Access is possible simultaneously with a voice call using the Wallset IP. There are two access rates: 35 kbps and 70 kbps, using one and two time slots respectively.
[attachment=51021]
ABSTRACT
The traditional wired local loop used to connect each telephone subscriber to the nearest exchange is expensive and unreliable. Wireless Local Loop (WLL) systems largely eliminate these copper wires using wireless technologies and could provide a cost effective solution. corDECT is one such WLL system, based on the DECT (Digital Enhanced Cordless Telecommunications) standard, that provides toll-quality voice and data capability at a cost below that of a wired local loop. Using micro-cells and Dynamic Channel Selection (DCS), it can handle high subscriber densities without frequency planning. corDECT is gaining commercial acceptance in India and a number of other countries.Using a simple Queueing Network Model (QNM), we find that the 1,000-line corDECT system could achieve a Busy Hour Call Attempt (BHCA) of 36,000 calls/hour, which is far greater than its requirement of 20,000 calls/hour. We show how the system could be expanded to a 10,000-line exchange with a BHCA of over 2,10,000 calls/hour. We also investigate the feasibility of implementing 64 kbps data service along with voice. It is shown that this requires modest hardware improvements.
INTRODUCTION
Traditionally, a pair of copper wires is used to connect each telephone subscriber to the nearest exchange. Such a wired local loop poses the following problems [6]:
_ The laying and maintenance of copper cable up to the subscriber’s premises incurs high cost. Also, this cost is increasing with time as the cost of copper increases.
_ The per-line cost for rural areas is significantly higher due to the large amount of cabling infrastructure required to take even a few telephone lines to remote villages.
_ Most faults are in the local loop, due to water-logging, damage or theft of cables.
_ Rapid deployment is difficult owing to the regulatory and other problems in laying buried cables.
ADVANTAGES AND LIMITATIONS
Voice Quality
corDECT delivers the same toll-quality speech performance as a good copper-based local loop..
Data Services
The employment of 32 kbps ADPCM permits all voice-band data services available from a conventional wired connection. It is also possible to occupy a double time slot on air to transmit at 64 kbps with error correction.
Internet Access Speed
Internet Access is possible simultaneously with a voice call using the Wallset IP. There are two access rates: 35 kbps and 70 kbps, using one and two time slots respectively.