Andrew Wireless Innovations Group RPT-MR801 사용자 설명서
M0050A0B.doc
Id.-No. 148222
Page 3 of 12
11-Mar-99
1 Functional description
The band module with variable bandwidth can be set to a desired centre frequency and to a
desired bandwidth.
desired bandwidth.
The explanation how it works is made with reference to the following figures and exemplary
values for frequencies, bandwidths and levels.
values for frequencies, bandwidths and levels.
There are two filters in one link (UL or DL) in series in the band module which can be set to a
defined centre frequency. In the example we have two filters with a bandwidth of 25 MHz
each and for demonstration purposes the frequency range is 870 to 940 MHz.
defined centre frequency. In the example we have two filters with a bandwidth of 25 MHz
each and for demonstration purposes the frequency range is 870 to 940 MHz.
In Fig. 1 we see that filter 1 and filter 2 are both set to a centre frequency (CF) of 900 MHz.
The resulting overall response of the module is thus a 25 MHz band with a centre frequency
of 900 MHz (
The resulting overall response of the module is thus a 25 MHz band with a centre frequency
of 900 MHz (
⇒
frequency range from 887.5 MHz to 912.5 MHz). The attenuation in the stop
band of one filter was assumed to be 40 dB. Thus, the overall attenuation of the module is
80 dB.
80 dB.
Fig. 1
Fig. 2