The DF-A0137 from Alaris Antennas is a high-speed, 4-band switch intended for direction finding applications.

It accepts four frequency bands, each with five antenna elements, and outputs the elements of any one band to the corresponding five RF outputs.

The switch is controlled via an EIA-485 (RS-485) serial interface to allow remote control over a distance of up to 500 m. All switching is solid state for rapid and unlimited switching cycles.

The DF-A0137 includes an internal noise source as well as an external input for chain calibration purposes. Either the internal noise source or the external calibration input may be selected to simultaneously inject a balanced signal in place of the antenna inputs and thereby correct errors caused by variations in the system’s RF path.

All inputs of the DF-A0137 are equipped with limiters to allow it operate in harsh EMC environments.

DF-A0137 Features

DF switch

  • 4-band switch
  • External injection mode for chain calibration
  • Internal chain calibration noise source
  • Low noise amplifier on each channel
  • High-speed solid state switching

Monitoring

  • Single-channel amplifier
  • Low noise pre-amplifier on input
  • DC-injection to power upper stages

Advanced input stages:

  • Limiter on each input to allow operation in adverse EMC environments
  • ESD protection

Advanced output stages:

  • Output amplifiers for long cables
  • Cable slope correction on amplifiers
  • ESD protection