08 Mar 2007
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Bulk acoustic wave delay lines
Bulk acoustic wave delay lines operating at microwave frequencies are compact devices that provide a few micoseconds of delay for R.F. signals with bandwidths of a few gigahertz.
In the past we have designed, manufactured and supplied devices that have delays ranging from 2.5µs to 18.75µs with bandwidiths greater than 2GHz. The current delay line project will deliver over 500 devices into Tranche 1 of the Eurofighter programme and 1000 into Tranche 2 over the next 5 years. Since the velocity of acoustic waves is of the order of 100000 less than electomagnetic waves, acoustic delay lines offer relatively large delays in a small volume.
Such devices consist of transmitting and receiving transducers. Using lithium niobate for the transducers and yttrium aluminium garnet for the delay medium, losses of less than 30 dB are easily achieved with all spurious reponses suppressed by greater than 30 dB. Using internal equalisation networks devices can be made to closely track a predetirmined insertion loss profile. Devices are designed and tested to meet military enviromental specifications and are manufactured under ISO 9001:2000 quality management system.
