In microwave communication application circulators / isolators occupy the focus position in modern communication , plays an irreplaceable role in other components . p>
The mobile communication means between the mobile user , a mobile user through the mobile communication traffic between a mobile station and the fixed station or the mobile has undergone analog voice communications ( first generation ) and digital mobile voice communication ( second generation ) , such as GSM, CDMA dynasties, has now entered the global coverage of multimedia communications - the third generation , one of its main features is to achieve global roaming , so that at any time , any place any exchanges between people , made possible ; the future is the development of the fourth generation - high-speed mobile communications. These belong to the list of wireless communications systems , the transmission of them to be used as a means of microwave , so microwave ferrite circulators, isolators are indispensable basic device . The circulator / isolator in the mobile communication base station in the main (station ) and the mobile station system. In the main base station and a mobile station as received , the transmitter antenna sharing unit ( duplexer or multiplexer ) for power amplifiers, switches input and output isolation amplifiers in transmission and reception systems. p>
Wireless relay apparatus and the base station p>
When the train made use of the principle of tunnels leaky coaxial cable communication system , when the tunnel for a long time to the creation of several repeaters in the tunnel in order to achieve effective communication . microstrip isolator, microstrip circulators important applications in microwave communication span> p>
In the wireless base station apparatus , the mobile station and the channel number , must adequately intermodulation carefully considered. When the base station are distributed , the mobile station will receive a different signal strength of several emitted transmit antenna produces a frequency modulation mutual interference of the useful signal received ; channel between the intermodulation products are inevitably produced . To this end the transmission system using the centralized base station mode , a common transmitting antenna , using a circulator and a bridge circuit to achieve a base station transmit antennas to pay a plurality of channels available for use, and on each line transmitter use of an isolator. The base station receiving system, since the distribution of the loss of much of each channel by using an antenna does not meet all the requirements of the common channel , a plurality of antennas so take a common channel mode . p>
Mobile phone p>
With the continuous development of mobile communication technology, its basic requirements circulator / isolator is a high-performance ( low insertion loss , high isolation, wide-band , high-power and high- temperature stability , etc. ) , small, lightweight , Low cost , particularly for mobile phone devices , small, lightweight and low cost is particularly important. Similarly for handheld digital telephone system circulators / isolators are made diplexer and transmit power amplifier output isolation decoupling. p>
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