Band Pass Filter (BPF) and Cavity Diplexer have one thing in common that they both have to deal with frequency filtering. BPF lets only the frequency of a particular range to pass while Cavity Diplexer keeps frequencies separated that are received and transmitted.
Band Pass Filter
Band Pass Filter is the combination of Low Pass Filter (LPF) and High Pass Filter (HPF) to let pass the frequencies of the desired range to eliminate the disturbance elements. It also optimizes the signal-to-noise ratio. These are used in all aspects of telecommunications, Sonar, Seismology and medical equipment such as EEGs and Electrocardiograms.
Cavity Diplexer
The Cavity Diplexer keeps the frequencies received and transmitted separated. It is a three-port device and covers all frequency bands ranging from higher to lower. The commercial diplexer is designed as cavity notch, hybrid ring, and band pass or band-reject. Every design has its own advantage and an objective. So, all of these solve your different problems. A commercially manufactured diplexer is more efficient and convenient to use.
Both of these solve different purposes but their collective efforts result in precise output or to have one made to your needs, ensuring high-quality data transfer be it video, sound or text. These have revolutionized the communication industry by facilitating interruption-free data transfer.
You can find a wide range of both Cavity Diplexer and Band Pass Filter online at the Raditek website.