Author: Janne Tuomisto

Name of the Thesis: The implementation of Inverse Multiplexing for ATM (IMA) in a switching platform

Date: 10.6.1999
Number of pages: 64

Faculty: Department of Electrical and Communications Engineering

Professorship: S-72 Communications Engineering

Supervisor: Professor Seppo J. Halme

Instructor: MSc Jan Hellström

The third generation cellular networks demand more flexibility and capacity from transmission networks than the PCM time slot based transmission systems can provide. One strong alternative for this task is ATM, the flexibility of which can be increased by taking Inverse Multiplexing for ATM (IMA) into use. With the IMA the ATM traffic can be shared between several physical interfaces so that this operation is transparent to the ATM layer. The greatest advantage of IMA is that it enables the use of the existing transmission network systems for delivering broadband ATM connections. The transmission solutions of the second generation mobile networks are mainly based on the primary rates of PDH networks. With the help of IMA the same transmission networks can be reused in third generation cellular networks.

In this master's thesis the hardware implementation of IMA is designed for the Nokia Telecommunications DX 200 system. The second and the third generation cellular network implementation based on the DX 200 system are introduced in the beginning of the thesis. Also some reasons why the PCM time slot based system is not the best potential alternative for the third generation are introduced. The IMA function, its management and the management software implementation principles are covered. The actual hardware design work begins by defining the requirements and the operational environment. The next step is to choose the components used in the implementation. The hardware, which implements the IMA function, is presented by component basis. The schematics of the design are included in the appendixes.