Process for the transmission of data by a multi-user, point to multi-point digital data transmission system

• US 20050018703A1
• Filed: 07/16/2004
• Published: 01/27/2005
• Est. Priority Date: 01/18/2002
• Status: Active Grant

• Current Assignee: Maxlinear Hispania SLU (Maxlinear Incorporated)
• Original Assignee: Diseño de Sistemas en Silicio SA (Marvell Technology Group Limited)
• Inventors: Blasco Claret, Jorge Vicente, Riveiro Insua, Juan Carlos, Carreras Areny, Judit, Ruiz Lopez, David
• Granted Patent: US 7,483,435 B2
• Time in Patent Office: Days
• US Class Current: 370/432
• CPC Class Codes: H04J 3/1694 Allocation of channels in TDM/TDMA networks, e.g. distributed multiplexers Passive Optical Networks H04Q11/0062
• CPC Class Codes: H04J 3/22 in which the sources have different rates or codes simultaneous speech and digital data or video transmission H04M11/06; see provisional also H04J3/16
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 47/24 Traffic characterised by specific attributes, e.g. priority or QoS
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex

Abstract

The invention relates to a data transmission method for a multi-user, multipoint-to-multipoint digital data transmission system involving a plurality of pieces of user equipment (1) which are bidirectionally connected via a physical means (6). The inventive method can be used to establish various communications from a piece of user equipment (1a) to different pieces of destination user equipment (1b-1d) at different speeds, while maintaining the bandwidth and maximum latency values required by each of the pieces of destination user equipment (1b-1d). Said method consists in sending multiple information frames (4) from a piece of equipment (1a) to a multitude of pieces of destination user equipment (1b-1d) at different speeds. Moreover, using the percentage reserve of the frame, the invention provides a quality of service based on that required by the piece of user equipment and supplies a criterion for dynamically assigning the packets which are sent to each piece of user equipment in the frame, grouping or dividing the packets to be sent.

Claims

1. PROCESS FOR TRANSMITING DATA BY A MULTI-USER, POINT TO Multi-point digital data transmission system, where various user modems are in two-way communication over a physical medium, a downstream channel being the channel used in the communication between a user modem and numerous addressee user modems, and an upstream channel being that used in the communication to this specific user modem;

wherein the process comprises;

carrying out the transmission of information at various speeds to various user modems over the same physical medium;

carrying out time division in the down-stream channel adaptable to the different transmission speeds of the different addressee user modems;

optimizing a size of a packet to the communications means, and this packet size may be different to that used in upper layers of the communication from the transmitter;

carrying out packet transmission with different priorities by means of reservation of channel time based on a quality required by the addressee user modems or groups of addressee user modems;

dividing the downstream link in a series of frames with a fixed lenght where various percentages of the packets sent in the same frame are reserved for the various groups of addressee user modems that share the same quality of service, in terms of criteria selected from reserved bandwidth, maximum latency and combinations thereof;

all of which in order to guarantee a fixed bandwidth and a fixed maximum latency for the various addressee user modems in the downstream channel, and adapting quality of services (QoS) for a communication traffic to different requests for bandwidth and latency.

2. PROCESS FOR TRANSMITING DATA BY A MULTI-USER, POINT TO MULTI-POINT DIGITAL DATA TRANSMISSION SYSTEM, according to claim 1, wherein time division in the downstream channel that is adaptable to the different transmission speeds of the different addressee user modems is undertaken by sending packets of different length in a same channel time, so that information is transmitted at different speeds, depending on a number of usable bits per symbol for each one of the addressee user modems by means of packets with a maximum length fixed in number of bits.

3. PROCESS FOR TRANSMITING DATA BY A MULTI-USER, POINT TO MULTI-POINT DIGITAL DATA TRANSMISSION SYSTEM, according to claim 2, wherein to occupy the same channel time a number of symbols to be sent in a packet transmission unit (Maximum Transfer Unit or MTU) of the transmitter is fixed, said number being adjusted to reach a compromise between transmission efficiency in bits per second and quality of service in terms of latency, in order to allow selectively different types of traffic selected from traffic without minimum latency and bandwidth requirements, traffic with constant bit rates (CBR), traffic with variable bit rates (VBR) and traffic with reserved bandwidth and fixed maximum latency.

4. PROCESS FOR TRANSMITING DATA BY A MULTI-USER, POINT TO MULTI-POINT DIGITAL DATA TRANSMISSION SYSTEM, according to claim 3, wherein the packets that must be sent to the various addressee user modems are grouped and/or divided in the transmitter so that they occupy the size fixed in number of symbols in the Maximum Transfer Unit (MTU).

5. PROCESS FOR TRANSMITING DATA BY A MULTI-USER, POINT TO MULTI-POINT DIGITAL DATA TRANSMISSION SYSTEM, according to claim 1, wherein if an addressee user modem or group of addressee user modems do not use the percentage reserved for them, said percentage is divided between the rest of the modems or groups of modems to whom information is being transmitted, in function of a determined configuration of selected traffic.

6. PROCESS FOR TRANSMITING DATA BY A MULTI-USER, POINT TO MULTI-POINT DIGITAL DATA TRANSMISSION SYSTEM, according to claim 1, wherein within the percentage of packets in the frame reserved for a group of addressee user modems, each modem has its own percentage of packets depending on the quality of service requirements in terms of a criteria selected from reserved bandwidth, maximum latency and combinations thereof.

7. PROCESS FOR TRANSMITING DATA BY A MULTI-USER, POINT TO MULTI-POINT DIGITAL DATA TRANSMISSION SYSTEM, according to claim 1, wherein the packets that must be transmitted are stored in user queues ordered by priority, where these priorities are fixed by a higher layer protocol to allow extraction of the packets ordered according to a priority established, so that the transmitter groups packets and determines which is the next packet to be sent, to which user and the size of that packet.