Error detection/correction and fault detection/recovery – Data processing system error or fault handling – Reliability and availability
Patent
1996-08-13
2000-07-18
Grant, William
Error detection/correction and fault detection/recovery
Data processing system error or fault handling
Reliability and availability
714749, 714752, G06F 1100
Patent
active
060922222
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to data transmission in a system employing information channels having at least two different capacities, on which channels speech is transmitted by at least two different coding techniques in such a manner that on a channel having a higher capacity, essentially fewer symbols to be transmitted are coded from the same speech signal block than on a channel having a lower capacity.
BACKGROUND OF THE INVENTION
In designing data transmission systems, especially cellular radio systems, two essential aspects have to be especially taken into account. Firstly, the required geographical area is to be covered at low costs. Secondly, information is to be transmitted with the smallest possible number of transmission errors.
It is typical of digital data transmission systems in which speech information is transmitted that they apply speech coding, to change analog speech into a digital form. For instance in a fixed telephone network, analog speech is changed into a digital signal the bit rate of which is 64 kbit/s. In many data transmission systems, for instance in cellular radio systems, this transmission rate is impractical since it requires too much transmission capacity. The speech coding used in these systems is thus implemented, if possible, using a transmission channel and a bit rate as small as possible.
Speech coding techniques are constantly studied, and thus, for instance in designing cellular radio systems, the development of technology has been taken into account by making an allocation in the system for the use of better speech coding algorithms. This is the case for instance in the GSM (Groupe Special Mobile) system, in which is specified a so-called half rate codec, the bit rate of which is half of the bit rate of a so-called full rate codec. With the use of a half rate codec, the capacity of the system can thus be increased, since the amount of bits to be transmitted is half of what it used to be. For instance, in TDMA (Time Division Multiple Access) systems, it is thus possible to transmit a double amount of coded speech in the same amount of time.
In constructing a radio telephone system, attempts are thus made to produce a desired coverage area at lowest possible cost. In considering the location of the base stations of the system, both the required traffic capacity and the produced cell size are taken into account. In areas where the expected amount of traffic is great, cell sizes are small, whereas in sparsely populated areas where the required traffic capacity is small, attempts are made to produce as large cells as possible. Transmission capacities used at base stations and terminal equipment thus increase. In some cases, where it is uneconomic to construct a dedicated base station, it is possible to use a separate repeater, which receives signals arriving from a base station and repeats them within its own area. Costs can thus be reduced to some extent, however not significantly.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to extend the cell size of a radio telephone system and thus the coverage area of the system without great changes in the equipment and particularly without an increase in transmission power. A further object of the invention is to implement advantageously a cellular system cell which has an essentially larger coverage area than before, without the used transmission capacities increasing essentially.
This is achieved with method, characterized in that a signal transmitted on at least one channel having a lower capacity is speech coded according to a channel of a higher capacity, and that channel coding is performed on the data speech coded in this manner in such a manner that the obtained number of symbols corresponds to the channel of a lower capacity.
The invention further relates to a data transmission system employing information channels having at least two different capacities, the speech transmitted on said channels being coded by at least two different coding techniques in such
REFERENCES:
patent: 4472802 (1984-09-01), Pin et al.
patent: 4972483 (1990-11-01), Carey
patent: 5091945 (1992-02-01), Kleijn
patent: 5182753 (1993-01-01), Dahlin et al.
patent: 5208812 (1993-05-01), Dudek et al.
patent: 5260700 (1993-11-01), Merchant et al.
patent: 5299198 (1994-03-01), Kay et al.
patent: 5303234 (1994-04-01), Kou
patent: 5327576 (1994-07-01), Uddenfeldt et al.
patent: 5357513 (1994-10-01), Kay et al.
patent: 5404355 (1995-04-01), Raith
patent: 5422932 (1995-06-01), Kay et al.
patent: 5502721 (1996-03-01), Pohjakallio
patent: 5666370 (1997-09-01), Ganesan et al.
Bersford-Smith, "Systolic Divices For Speech Processing", IEEE, pp. 2-88 - 2-90, 00/1989.
Falciasecca, "Investigation on A Dynamic Channel Allocation For High Capcity Mobile Radio Systems", IEEE, pp. 176-181, 00/1988.
Heralall. "High Capacity Cellular Patterns For Land Mobile Radio Sysstems Using Directional Antennal", IEEE, pp. 75-80, Feb. 1989.
Whiting, "Performance Bounds For Cell Management Schemes In Cellular Radio" IEEE, pp. 17/1-17/10, 00/1989.
Beck, "Strategies For Handover And Dynamic Channel Allocation In Micro-Cellular Mobile Radio Systems", IEEE, pp. 178-185, 00/1989.
Akeberg, "Properties Of A TDMA Pco Cellular Office Communication System", IEEE, pp. 186-194, 00/1989.
Nettleton, "A high Capacity Assignment Method For Cellular Mobile Tlephone Systems" IEEE, pp. 395-637, 00/1989.
Barkry, "computer Investigations Of Telephone-Trafic For Cellular Mobile Radio Systems", IEEE, pp., 00/1989.
Dunlop, "Speech Trafic Capacity Of Idle-Signal Casting Multiple Access With Colosion Detection (ICMA/CD) For Cellular Mobile Radio", IEEE, pp. 1-5, 00/1989.
Mouly and Pautet, The GSM System for Mobile Communications, published in 1992, pp. 79-122 ISBN 2-9507190-0-7.
IEEE International conference on Acoustics, Speech and . . . , vol. 1, 1994, (New York), Jorg-Martin Muller et al, "A Codec Candidate for the GSM Half Rate Speech Channel", p. 257 - p. 260, see especially ch 2.2.
Jolma Petri
Wang Ling
Grant William
Marc McDieunel
Nokia Telecommunications Oy
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