This product comes from Alaris Antennas catalogues

Monitoring Antenna


The OMNI-A0258 is a vertically polarised omni-directional antenna consisting of an antenna array, covering 20 to 9000 MHz. The antennas are combined under a single compact radome and output either in a single (OMNI-A0258/-01/04) or two (OMNIA0258-02) connectors. In the active versions of the antenna the active part protects the system from excessive field strengths and boosts low level signals.The active version of the antenna relies on DC power injection on the output port of the antenna. The antenna is best utilised with the MISC-A0080 power supply for this purpose. The OMNI-A0258-01 features a passive-bypass mode which is engaged when the antenna is not powered. In this mode, the antenna is completely passive, allowing for low distortion measurements in the presence of high incident fields. Similarly, this also applies to the passive only OMNI-A0258-04. The antenna features lightning protection measures against induced surges on the RF feeder cables as well as ESD protection. The rugged design of the antenna allows it to be deployed on vehicle platforms.

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Frequency range* Band A: Band B: 20 - 1000 MHz 1000 - 9000 MHz
Gain See figures 1 & 2
Nominal H-plane 3 dB beamwidth 360°
Nominal E-plane 3 dB beamwidth 60°
Azimuth ripple (RMS) Band A: ±1.5 dB Band B: ±3.0 dB
VSWR (typ.) ±3.0 dB VSWR (typ.) < 2.5:1
Polarisation Linear
RF power rating Receive only
Connector type N-type female
Input voltage (via coaxial cable.) 13 - 24 VDC
Input current < 150 mA
OP1dB (typ.) (in active mode) 11 dBm
OIP2 (typ.) (in active mode) 32 dBm
OIP3 (typ.) (in active mode) 22 dBm
Sensitivity See figure 3

    Product Applications

    Spectrum Management
  • Spectrum Monitoring
  • Radio Direction Finding
  • Signals Intelligence

    Design Features

  • Ultra wideband 20 to 9000 MHz Protected against excessive field strengths Very good sensitivity Low profile compared to passive alternatives Robust IP63