Nova Patents
EP0804006A2

Medium access control scheme for a wireless access to an ATM network

Abstract

According to the present invention, an adaptive and efficient MAC protocol for wireless access to an ATM network (32) is capable of supporting any type of ATM service class with associated Quality of Services parameters. An ATM cell-switched architecture is utilised in which several ATM Mobile Terminals (10,12,14,16) within a given geographic cell (small cells covering a range of several tens of meters) communicate with an ATM Access Point (18,20) using radio frequency channels, which is connected to an infrastructure ATM network by the means of conventional ATM links. Mobile Terminals can operate both indoor and outdoor with limited range and have wireless access to the Access Points on the ATM network.

EP0804006A2, drawing sheet 1
Sheet 1 of 11

Term

Term ended

Projected expiry passed 8 April 2017, 9.5 years ago.

  1. Priority
  2. Filed
  3. Published
  4. Projected expiry
  5. Today

26 claims: 10 independent, 16 dependent

  1. 1
    In a data communication system of the type comprising:at least one first network based on a first technology and including at least one first station, at least one second network based on a second technology being different than the first technology, and including at least one second station, access means for providing communication between the at least first and second stations, said system being characterized in that said access means comprise: ■ means for defining a plurality of successive time frames during which traffic of data from said first or second network is carried out, and ■ means responsive to network parameters of each said first and second networks, and to traffic characteristics and constraints, for scheduling the exchange of data information during each said successive time frames.
  2. 5
    The system of anyone of claims 1 to 4, wherein said successive time frames are divided into three periods, the first period for contention free transmission from said first network to said second network;the second period for contention free transmission from said second network to said first network;and the third period for contention based transmission from said second network to said first network.
  3. 10
    The system of anyone of claims 1 to 9, wherein said first network is an ATM network (32), said second network is a wireless network comprising a plurality of Mobile Terminals (10,12,14,16), each Mobile Terminal including a transceiver (46) and wherein said access means comprise an Access Point (18,20) having a transceiver (38) for radio communication with the transceivers of each of the plurality of Mobile Terminals.
  4. 13
    The system of claims 10, 11 or 12, wherein several ATM cells can be transmitted either by the Access Point or by said plurality of Mobile Terminals, during a sequence of contiguous time slots, forming a cell train.
  5. 14
    The system of anyone of claims 10 to 13, wherein said Access Point or said plurality of Mobile Terminals further comprising means for storing the ATM cells to be transmitted in memory buffers having the structure of a said cell train.
  6. 15
    The system of anyone of claims 10 to 14, further including means for ensuring that the part of said ATM traffic which has been guaranteed by an ATM connection contract established at an ATM connection set-up, is carried over a wireless channel between said Access Point and said plurality of Mobile Terminals using a reservation based, contention free access method.
  7. 20
    The system of anyone of claims 1 to 19, wherein said plurality of Mobile Terminals further comprising means for scheduling said ATM traffic during said time frame, conjointly within said Access Point.
  8. 23
    The system of anyone of claims 20 to 22, wherein the scheduling means of said plurality of Mobile Terminals comprise means to schedule transmission of ready to be sent ATM cells within the sub-set of said second period which has been allocated to it by the scheduling means of said Access Point.
  9. 24
    The system of anyone of claims 20 to 23, wherein the scheduling means of said plurality of Mobile Terminals comprise means to schedule transmission of ready to be sent ATM cells during said third period, if said ready to be sent ATM cells cannot wait the next time frame before being transmitted to said Access Point.
  10. 25
    The system of anyone of claims 10 to 24, wherein the scheduling means of said Access Point broadcast to said plurality of Mobile Terminals at the beginning of each time frame, a frame header control packet specifying the structure and the content of said time frame.
Independent claims10