The cavity diplexer (also known as the base station diplexer) is composed of two sets of band-stop filters of different frequencies, whose role is to isolate the transmitted and received radio signals from each other, to avoid the transmission of the local transmitted signal to the receiver, so as to ensure that the receiving and transmitting can work normally at the same time. Its structure is composed of a common node (antenna) and two filters (receive and transmit), allowing the device to transmit (that is, TX) and receive (that is, RX) signals at the same time, and the diplexer is the main accessory for cross-frequency duplex radio and repeater stations
Cavity diplexers are commonly used in frequency division duplex (FDD) radio applications, where one filter is the transmitting filter and the other is the receiving filter. The design of cavity diplexers needs to ensure that the passband of each filter does not load another filter. Moreover, the transmitted signal appearing in the receiving filter output needs to be significantly attenuated, and this high level of isolation is required to ensure that the signal does not cause overdrive in the receiving front end. This isolation is called transmit-receive isolation at the transmission frequency, and its common value is generally more than 55dB. Similarly, a high level of transmit-receive isolation is required at the received frequency to prevent the wide offset noise (received frequency) generated by the transmitted signal from appearing in the receiver input, thereby reducing sensitivity. The above two isolation requirements constitute the "in-band isolation requirements", that is, the receive/transmit filter corresponds to the same frequency band.
二、Model & Electrical characteristics
Cavity duplexer (base station duplexer or GSM duplexer) model and parameter table
Part No
Center frequency
(MHz)
Band Width
(MHz)
Insertion loss
(dB max)
Ripple
(dB max)
Power
(W max)
Attenuation(dB min)
Size(mm)
CFD15R193A
TX
935.5
179
0.6
0.3
700
80@722~778 MHz
10*99*30
RX
1706
166
0.6
0.3
700
80@722~778 MHz
CFD8R168A
TX
5100
200
0.8
1.3
300
25@5800 ≤ f ≤ 6000 MHz
52*28*11
RX
5900
200
0.8
1.3
300
25@5000 ≤ f ≤ 5200 MHz
CFD10R171A
TX
6300
600
0.5
1.3
100
50@6940 ≤ f ≤ 7350 MHz
34*34*13
RX
7145
410
0.5
1.3
100
70@6000 ≤ f ≤ 6600 MHz
CFD12R152A
TX
1450
134
0.6
1.5
1000
55@f ≤1280MHz
50@1574≤ f ≤1280MHz
127*50*30
RX
1699.5
147
0.6
1.5
1000
55@f ≤1280MHz
50@1574≤ f ≤1280MHz
CFD16R164A
TX
1437.5
175
0.7
1.3
250
55@f ≤1280MHz
50@1574≤ f ≤1280MHz
134*108*30
RX
1705
160
0.7
1.3
250
50@1574≤ f ≤1280MHz
40@1830≤ f ≤1835MHz
CFD18R183A
TX
1437.5
96
0.5
0.3
1000
70@846~2400 MHz
179*159*53
RX
1705
268
0.5
0.3
1000
70@100~796 MHz
CFD1320~8615A
TX
948
20
1.5
0.5
3.0
50@8540~8690 MHz
70*60*30
RX
824
150
2.0
0.5
3.0
50@DC~1360 MHz
CFX6R199A
CH1
1320
4.1
1.0
0.5
10
70@5800~60000 MHz
110*45*20
CH2
8615
4.1
1.0
0.5
10
80@1000~4000 MHz
CFX3R146A
CH1
5179.25
4.0
1.7
0.65
10
70@5800~60000 MHz
111.4*50*25
CH2
5159
4.0
1.7
0.65
10
80@1000~4000 MHz
CH3
5171.76
4.0
1.7
0.65
10
Note: Due to many product models, only some representative models are listed in the table
三、Application & attention
The cavity diplexer (also known as the base station diplexer, or GSM diplexer) is composed of two sets of band-stop filters of different frequencies, whose role is to isolate the transmitted and received radio signals from each other, to avoid the transmission of the local transmitted signal to the receiver, so as to ensure that the receive and transmit can work properly at the same time. Duplexer is the main accessories of different frequency duplexer radio and repeater station, mainly used in base station, radar, T/R components, RF microwave, repeater, mobile communication field and consumer electronics products.
This kind of product belongs to the relatively strong customization of the product, for different users have different requirements for parameters, for each user needs to be designed and produced separately. Users who have special requirements for the shape structure can use the shape size provided by the user to process the structure requirements. The company can customize cavity diplexer, cavity multiplexer, cavity high-pass filter, cavity low-pass filter, cavity band-stop filter, cavity band-pass filter. The custom cavity diplexer requires the user to put forward reasonable requirements, and the parameters beyond the physical limit of the material can be negotiated to achieve the best indicators.
