With higher frequency signals, it is important to use electronic components that are rated to handle such frequencies to avoid noise and signal degradation. When designing a high frequency relay, an engineer will evaluate the following characteristics:
- 1) Isolation - Resistance to signal leakage when the contact and terminal are open or resistance to cross talk between adjacent channels. Isolation is measured in dB (Decibels).
- 2) Insertion Loss - The signal loss that occurs between the contact and the terminal when the circuit is closed. The amount of loss is represented in dB.
- 3) Impedance - Transmission lines have characteristic impedance. It is imperative that impedance in the circuit is matched. Typical impedance for communication lines is 50W and for cable is 75W.
- 4) VSWR (Voltage Standing Wave Ratio) - In high frequency transmissions, signals reflect due to circuit impedance mismatch. VSWR is the ratio used to identify the degree of impedance mismatch.
The Panasonic brand ARJ relay is a compact RF relay with excellent high frequency characteristics tested up to 8GHz. The ARJ is designed to meet the toughest demands of high speed communication networks and test equipment. It's available in 2 Form C configuration 50 ohm impedance, 0.5dB insertion loss and VSWR of 1.25.
Typical Applications:
- 1) Measurement equipment - Attenuator circuits, spectrum analyzers and oscilloscope.
- 2) Mobile communications - IMT 2000, Microwave communications and tower top amplifier redundancy circuits.
The cost competitive ARD Coaxial switch provides stable RF performance, up to 26.5GHz, with long life. It is available in SPDT and SPST arrangements. The ARD switch is available in latching, fail safe and TTL drive latching type with self cut-off circuit, in 12 and 24VDC.
Typical Applications:
- 1) Satellite communications
- 2) Up/down converters
- 3) Test equipment
- 4) PCS equipment
- 5) VXI bus test equipment
- 6) Antenna top amplifiers / redundancy
- 7) LMDS
In addition to the ARJ and ARD, Panasonic offers these other HF types:
- ARA, low profile 1GHz, 2C, 50ohm, SMT
- ARX, low insertion loss, 3GHz, latching coil available
- RK, 75 ohm impedance, 1.5 GHz, latching coil available
- ARE, low cost 2.6 GHz, 50 & 75 ohm, available in SMT
