RF and Microwave switch matrix is an RF subsystem that has a control circuit to route RF signals from the different input ports to different transmission paths ( Output port) with a high degree of efficiency. RF switch matrix will have multiple input and multiple output paths.
Five fundamental parameters of an RF and microwave switches matrix are the number of input and output ports, isolation between the channels, insertion loss through the channel, switching time of the controller, and power handling capability of the RF switch matrix.
In this article about the RF switch matrix, we will cover the following topics.
In general RF switches, matrices are available in Coaxial packages with USB, Ethernet, control interfaces for the switching among different channels. Now waveguide RF switch matrices are available for high power and frequency applications.
To learn more about RF and Microwave, we recommend you to check the following article.
To understand the RF switch matrix, we recommend understanding more about the following components by checking the respective pages.
The need for RF and microwave signal switching is increasing in the range up to 40 GHz, the application of an RF switch matrix with connectors and waveguide package is also in high demand.
Efficient RF signal switching from the input ports to the respective output ports is a vital part of the RF system design. In the world of 5G, RF signal switching among the multiple-input ports to the multiple-output ports (MIMO), one of the prime requirements.
RF switches matrix are categorized on the basis of Technology and Number of RF input and output ports.
RF switch matrices are usually made of RF switches mainly of the following 5 types.
In the RF switch matrix using electro-mechanical RF switches, motor-controller and manual mechanical control are used for the switching of the patch. Due to coils and mechanical contacts for switching Electromechanical RF switches assembles are of larger assemblies.
In the Electromechanical RF switches matrix, switching can be controlled remotely through LAN, USB etc.
Solid-state RF switches matrix, semiconductor materials are used for the switching relay of RF switches. In “on” and “off” transition will be in microseconds for the solid-state RF switch matrix and the overall package will be very smaller compared Electromechanical RF switch matrix.
Absorptive RF switch matrices are terminated with a 50-Ω load in all the output ports. Internal termination offers low VSWR (voltage standing wave ratio) for both states of the RF switch. In absorptive RF switch matrix the internal terminating resistance absorbs the incident RF signal energy hence it avoids the reflection of RF signal from the unterminated RF port.
Reflective RF switches matrices are not terminated internally with RF Terminators. In the open ports of reflective RF switches, the signal will get reflected and it offers lower insertion loss. Reflective RF switches matrix can be used for the circuit where VSWR isn’t critical.
In the PIN diode RF switch matrix, diodes are used for switching the RF signal between the RF input and output ports.PIN diode RF switches offer high switching speed compared to Electromechanical RF switch matrix
In the MEMS RF switches matrix, the switching mechanism is based on cantilevered MEMS elements. It is an electronically controlled switch matrix that provides metal-on-metal contact for the RF and microwave signal to flow from the input RF port to the output port.
For high-frequency applications, the number of waveguide switches as per the requirement are assembled in a box, which can cover required frequency bands. Waveguide RF switch matrices are bulk in the package and slow in switching operation, however, which can handle higher power and long-lasting assemble.
RF switches matrix is available in are several design configurations for the number of RF input and output ports. These port no can be easily configured on the basis of the number of RF input and output port requirements. RF connectors can be easily configured for each of the RF input and output ports are the system requirements.
Mechanical and solid-state RF switches matrix in any combination of the number of RF ports are available with 50-ohm and 75-ohm impedance matches.
In general RF switches, matrices are used to root the RF signal in different RF channels. On the basis of application, we can classify them as multiplexers, relay switches, and MIMO switch assemble.
Relay RF switches matrices are typically in use to route one input RF signal to multiple output channels.
Switching RF signal from an antenna to multiple receiver channels.
Multiplexer RF switch matrix can be used to route multiple input RF signal to a single source.
Multiplexers are used to switch multiple sources of RF signal to a single antenna using a controller.
MIMO RF switch matrix is used to route multiple input RF signal to multiple RF output ports.
MIMO is used mainly for the 5G technologies were in need to switch multiple sources RF signal to multiple antennae for transmitting the signal.
When selecting an RF Switch matrix following are the main factors that RF system designers need to consider.
The designer needs to select the RF switch matrix which meets the number of input and output port requirements. For the critical application where refection of RF signal from the open port is a concern, the designer needs to select an RF switch matrix that is made of an absorptive type of RF switch.
RF switches that are used for the construction of an RF switch matrix are optimized for a particular frequency range of operation, hence the need to select an RF switch matrix that covers the full range of frequency operations.
Power handling of the RF switch matrix is based on the power handling of the RF switches used for the construction. Power handling indicates the maximum RF signal power an RF switch matrix can handle before breaking down. The power handling input port of the RF switch matrix indicates the amount of received power the RF switch matrix can handle without degradation of electrical performance.
Isolation of the RF switch matrix indicates the attenuation between the input and output ports of the RF switch matrix. Isolation of the RF switch matrix indicates how effectively a switch enters into its “off” state. The high isolation RF switch matrix is better for the design.
Insertion loss of the RF switch matrix is referred to as the amount of RF signal power lost during the transmission of RF signal from the input to the output port during its through pass state. Lower the insertion loss better is the RF switch matrix.
Switching time indicates the amount of time an RF switch matrix takes for changing its channel. The switching speed of the switch matrix is based on the switching speed of the RF switches used for the construction. Switching speed is the measurement of time an RF switch takes to change from one channel to another channel.
Characteristic Impedance of the RF switch matrix should be matched to the impedance of the RF system where it needs to operate. A perfect match of 50 ohms and 75 ohms are generally available for RF switches.
RF connectors of the RF switch matrix need to select as per the application where it is going to use. RF switch matrix assemblies can be constructed with different combinations of RF connectors in a single assemble as per the requirement.
RF Switches matrix is used to switch the RF and microwave signals among the different channels with lesser loss. RF and microwave switch matrices are available with different dimensional packages and connector options.
Below is the list of top-rated RF and Microwave switch matrix manufacturers listed with the RF and Microwave Community.
If you would like to add a new RF switch matrix manufacturer feel free to recommend us through the contact us or through the manufacture registration button on the top of the RFMWC website.
Thanks & Regards