Orolia GPS/GNSS passive anti-jam antenna offers horizon blocking

Model 8230AJ antenna from Spectracom

Designed primarily for applications such as homeland security, Spectracom’s 8230AJ antenna provides protection in high-interference environments where additional resilience is needed, such as communications networks, financial systems and power grids, the company said.

Orolia, through its Spectracom brand, said the antenna, Model 8230AJ, is a drop-in replacement for the company’s Model 8230. Its conical antenna pattern rejects interference from the horizon and is simple to mount using the same pipe supports, without new cabling. All that is required is a new bracket.

“Model 8230AJ is a high gain (40 dB) GNSS outdoor antenna covering GPS L1, GLONASS L1, BeiDou B1, Galileo E1, and QZSS L1,” said David Sohn, product manager at Spectracom. “It uses a three-stage low noise amplifier, a mid-section SAW, and a tight pre-filter to protect against saturation by high level sub-harmonics and L-band signals. It is designed especially for harsh environments, is IP67 rated, and improves resilience and protects against jamming and spoofing.”

According to the company, the AJ antenna rejects signals for the lower elevation angles – where most interference comes from – and only receives signals from the higher elevation angles where the satellites are. While this reduces the number of satellites the receiver will see, for timing applications only a few satellites are needed. Moreover, with multi-constellation receivers, an increasing number of satellites are available.

With the increasing prevalence of jamming and spoofing, industries with critical infrastructure must take measures against interference.  GPS and GNSS in general have well-known vulnerabilities and limitations that require protection and mitigation: the signals are easily disrupted by unintentional interference from radio transmitters, they are extremely weak, cannot penetrate buildings and can easily be jammed, and civilian signals are not encrypted and can easily be spoofed.

The new anti-jam outdoor antenna is appropriate for anyone who uses a time server, including Spectracom customers who own a SecureSync, VersaSync or Netclock, according to the company.

Image: Spectracom