Multiplex communications – Communication over free space – Combining or distributing information via frequency channels
Patent
1996-11-13
1999-03-30
Marcelo, Melvin
Multiplex communications
Communication over free space
Combining or distributing information via frequency channels
379202, 379267, 455454, H04Q 722
Patent
active
058897712
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a method for transmitting data packet blocks, as well as to a subscriber unit for a packet wireless network with multiple subscriber units for transmitting data packet blocks.
A method and a device of this kind are described in unpublished German patent applications P 43 04 906.0-53 and P 43 04 916.831, which have been submitted in the name of the applicant of the present application.
The method and subscriber unit described operate with a fixed frequency channel over which the packet data blocks are exchanged between subscriber stations and intermediate stations on the one hand, and a central station on the other hand.
With the rising volume of information to be transmitted, there is also an increasing need to operate a plurality such networks in supplementary fashion in geographical regions where other networks already exist. For physical reasons, however, the number of terrestrial wireless channels available is limited, so that efforts are being made at present, on both a national and international level, to make additional frequency channels available.
Moreover, in particular with networks that are designed for real-time transmission, a high signal-to-noise ratio and a certain redundancy must also exist; this requires additional frequency channel capacity. This is particularly important in digital voice networks which operate with the time-division, multiple-access (TDMA) system, since if the individually interleaved data packets cannot be transmitted at the required speed, this causes echo effects in conversations or severe transit time delays, both of which are undesirable.
In order to increase the signal-to-noise ratio, the region to be served is moreover often divided into subregions, in each of which only a portion of all the available frequency channels is used. For example the same frequency channels are not used in two immediately adjacent regions, which reduces crosstalk, for example. This method is referred to as "frequency reuse." The result of this is again that additional frequency channel capacities need to be provided, since the channels assigned to the particular network cannot all be used in a given sub-region.
The maximum channel capacity is furthermore determined by the very different load characteristics of the networks over time; for example, digital telephone networks experience very different loads at different times of the day. In order to make a channel available to the user at any time, however, the network provider must provide a large number of redundant channels.
Examples of such networks, that at present either have already been built up or are in the testing phase, are the GSM (Groupe Special Mobile) wireless network, a European digital wireless network in the 900-MHz range that in Germany is called the D1 or D2 network; or the PCN (Personal Communication Network), which operates in the 1.7/1.8-GHz range and in Germany is called E-plus. These networks cover a wide frequency range for terrestrial wireless communication, so that it is becoming increasingly difficult to provide channel capacity for additional services.
In view of the above it is an object of the present invention to provide the aforesaid method and the aforesaid subscriber unit in such a way that additional transmission capacity is provided in the terrestrial frequency spectrum. Already existing services are to be disturbed as little as possible. In addition, the technical complexity is to be kept within acceptable bounds.
According to the invention, this object is achieved by a method for the transmission of data packet blocks over multiple frequency channels that at least in part are already being used in an existing basic network for digital data and/or voice transmission, the new method comprising the following steps: technique, until all the data packet blocks of a transmission have been transmitted.
According to the invention, this object is further achieved by means of a subscriber unit for an auxiliary network with multiple subscriber units for transmitting packet dat
REFERENCES:
patent: 3781818 (1973-12-01), Pardoe et al.
patent: 4352183 (1982-09-01), Davis et al.
patent: 4747101 (1988-05-01), Akaiwa et al.
patent: 5130987 (1992-07-01), Flammer
patent: 5193101 (1993-03-01), McDonald et al.
patent: 5412658 (1995-05-01), Arnold et al.
patent: 5428819 (1995-06-01), Wang et al.
patent: 5475866 (1995-12-01), Ruthenberg
patent: 5548809 (1996-08-01), Lemson
Altvater Air Data Systems GmbH & Co. KG
Marcelo Melvin
LandOfFree
Method for transmitting data packet blocks and subscriber unit t does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for transmitting data packet blocks and subscriber unit t, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for transmitting data packet blocks and subscriber unit t will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1221164