| 摘要 |
<p>With the large number of mobile telecommunications systems in existence, there is a need to provide a terminal, known as an adaptive terminal, which can operate in these mobile telecommunication systems. Current terminal are dual/tri-band cellular telecommunication handset which have a chip set to facilitate operation within 2/3 bandwidths. However, the realisation of a handset capable of operating in 4 or more telecommunication systems is difficult, because the chip set supporting such a configuration would be extremely complex; the arrangement of filters in the receive and transmit chains would be complex. The present invention therefore provides a simplified handset structure which is a broadband structure, the circuit topology and design parameters therefore enabling the provision of filter modules which can easily be provided on a SIM card, or within the hand set itself. The advantage of such a system is that it allows the filtration elements to be produced as a module without increasing the overall complexity of the handset architecture.</p> |
