Ismaning/Chessington, 30 October 2002 - Willtek Communications today announced the latest addition to the Griffin series of RF Receivers. The new Up-Converter adds the frequency range from 300 to 500 MHz and meets the needs of network operators and RF planners for new radio systems now being widely installed such as TETRA, CDMA450 and GSM-R/ analogue. The new system is making it possible to take measurements during drive-by and through tests. More than 25 downlink channels can be sampled at speeds up to 100km/h and still meeting the ‘Lee-criteria’ (36 measurement on each frequency within 40 lambda) for valid local average power measurements of RF signals.

Characterising the RF signal behaviour is critical for all stages of  networks. Measurements at rollout allow the RF model to be calibrated for the real world environment that in turn identifies the optimum positioning of base stations to ensure coverage on all locations in the target area. During operation and on extensions, the network needs to be checked for no gaps in the coverage and to ensure compliance with any licence conditions.

Günther Klenner Product Marketing Manager at Willtek explains, “The wide instantaneous dynamic range of the Griffin at 80dB and the accuracy of ±1dB provides confidence in the RF channel measurements which leads to ensured coverage and higher quality of service for network users.”

Klenner goes on to say, “The channel measurement speed of the Griffin is unmatched by any other equipment as we use special receiver technology, so coverage tests and verification on existing and new mobile radio networks can now be made much faster than before.”

Used with the Willtek Hindsite software, the measurement data from the Griffin can be overlaid on topographical mapping details and compared to values from the RF model. This correlation of actual field and predicted signal strengths for the radio coverage allows fine-tuning on a range of network topologies.

The new 300 to 500 MHz Up-converter module is easily hooked -up to the Willtek Griffin Receiver with front panel connections providing a convenient lightweight package, making it ideal for efficient network coverage tests.

RF planners and engineering groups in network operators as well as infrastructure installation teams will welcome this addition as channel signal measurements will be faster. Finance managers will welcome the potential to reduce investment costs as fewer base stations will be required to provide effective signal coverage and faster revenue generation as networks turn-on quicker.

The standard Willtek Griffin Receiver provides fast measurements in the 800 to 1,000 MHz (cellular, GSM 900) and 1,700 to 2,000 MHz (PCS, GSM 1800) frequency bands. This rapid scan and sample rate of 1,000 channels and 100,000 readings per second increases the efficiency of drive-by testing in the cellular bands. The compact unit comes in a robust metal case weighing only 3.3 kg and the battery power provides ten hours of run time. This portability allows to do pedestrian coverage test in-door and out-door as well.

A separate module is available for the Willtek Griffin Receiver for UMTS frequency bands. The Griffin family now provides the industry with comprehensive coverage for all modern mobile radio networks. The accuracy and dynamic range of the Griffin, ensure the highest standards of measurements are available to the industry.

Note to editors

New radio systems are now being rolled out across Europe in the 300 to 500 MHz frequency range. The complex modulation characteristics used have increased the difficulty of accurately predicting signal levels and hence radio coverage. For safety critical systems in transport signalling networks such as GSM-R in combination with existing analogue communication systems or for Emergency Services (police, fireman, ambulance and so on) using TETRA. This means even greater emphasis on accurate RF modelling for prediction of coverage as well as tests on actual signal strengths where a radio is critical  for users in “life & death” situations.

In CDMA systems the experience of USA indicates that poor positioning of base stations through inadequate modelling or channel characterisation can lead to ‘pilot signal pollution’. This can produce cell hand-over problems with lost connections and frustrated users. CDMA 450 is an IMT-2000 (3G) standard.

The Lee-criteria for measuring the local average power of a mobile radio signal dates from work published in 1985 by William CY Lee. His conclusions of the number of samples and the number of wavelengths over which they should be measured have become widely accepted in the industry (white paper available).

Rail personal use two type of systems right now. Analogue communication system which differs from country to country but stays in the 300 to 500 MHz range and the new digital GSM-R in the 900 MHz range. Griffin with the Up-Converter covers both ranges allowing coverage verification with one tool.