The Virtual Field Test™ approach recreates the field conditions directly in the test lab (virtual reality), by combining accurate propagation simulation with hybrid implementation. Test engineers can then create various and significant traffic and mobility conditions, and therefore give a consistent validation of the handsets or equipment, saving most of the cost of real field trials.

This approach relies on Dynamo, a real-time system level dynamic simulator for emulating the whole UTRAN (UMTS Terrestrial Radio Access Network) virtually deployed. It takes benefit of the Flexcell™ Software Defined Radio Platform to generate a sophisticated combination of radio signals reproducing the interference conditions of the field.

• Device testing within a large set of mobiles (several thousands typically)

• Generation of a large number of cells (several 10s of Node Bs, typically)

• Generation of near real radio conditions (radio waves propagation maps)

• Actual operation/deployment cases import facilities

• Dynamic generation of mobile events and incoming/outgoing calls

• Easy generation of complex network simulation scenarios

• Support of 3GPP Release 99 FDD mode (W-CDMA)

• Mobility and service module editing tools

• System Level simulator generating real-time stimuli to the equipment under test

• Protocol stacks emulation with multiple contexts implementation

• Programmable Multiple Channel Simulator

• SDR (Software Defined Radio) technology for generation of complex composite radio signals

• RNC testing

• Node B testing

• Mobile Station testing

• "Natural" scenario generation

With Virtual Field Test™, a test case associates "a scene" with a set of simulation parameters: subscriber density, distribution of mobility (pedestrian, vehicular, etc.), distribution of traffic (voice, streaming video, packet). This set of parameters is customised for each geographical area defined in the scenario (e.g. hot spots).

• Put the equipment on stage

Simulation events (e.g handover) trigger message sequences, sent over the standardised interfaces of the device under test. Then, it dynamically takes appropriate actions in real-time, on the protocols carried over these interfaces (e.g. RANAP, NBAP, ALCAP, RRC,…).

• Business significance of test results

During the test, three monitoring tools display real-time indicators.

• The Signalling monitoring tool displays indicators linked to protocol management:

• 3GPP messages load

• Impact at system level (memory, CPU)

• Kiviat representation of messages flow for the different simulators

• QoS monitoring per traffic class (blocked calls, dropped calls, user satisfaction rate)

• History of the different signalling messages throughput

• The MSC viewer monitors signalling flow of the mobile under test

• The Virtual Field monitoring tool displays indicators linked to radio conditions in the system. They can be displayed either at system level (average value) or at cell or radio link level:

• Transmitted and received power

• Traffic load (UL and downlink capacity)

• Number of mobiles in soft handover

• Display of real-time OVSF codes allocation per cell

No need for code writing of testcases (TTCN, C code), just set up the scene via:

• Mobility Models

• Library containing user-defined models

• Speed, trajectory, location constraints, graph oriented,…

• Service Models

• Library containing user-defined models

• Data rates, asymmetry, session duration, QoS (Eb/Io), inactivity periods (DTX)

• Dynamic traffic mixes

• Multiple user-defined areas, each defining

• Subscriber density

• Traffic volumes per subscriber per service

• Distribution of mobility models

• Different Poisson laws in each area for generation of new calls at each simulation step

With Virtual Field Test™, it is easy to create a realistic situation in its whole complexity. Each test provides a higher coverage and requires less effort than with conventional testing :

• Test scenario quick and easy to custom

• High and significant test coverage

• large number of results/observations captured in a one-shot simulation

• quick and efficient analysis of consistent results

• Based on Linux PC

• Scalable platform (thread-safe independent stacks)

• Real-time operation

• Quick and easy upgrades and release updates due to flexible software implementation

Flexcell™ hardware platform

• High performance SDR platform based on the latest DSP and FPGA technology

• High reliability cPCI platform compatible with H.110 and PICMG 2.16 backplane

• Wideband radio front end with up to 2 receivers and one transmitter

• Up to 950MHz of discontinued bandwidth supported per system

• 30 Gbps high speed bus for internal communication

• Up to 64 frequency channels per Digital Processing Board