8230AJ/8231AJ GPS/GNSS Anti-Jam Antenna
Mountable, weather-proof protection
The Model 8230AJ or Model 8231AJ (our new triple-band version) is a high gain (40 dB) GNSS Anti-Jamming antenna made for outdoor conditions. 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. This GNSS / GPS anti-jam technology rejects signals for the lower elevation angles – where most of the interference comes from.
Mountable & Weather-Proof Anti-Jamming
The anti-jam antenna is terminated with a type “N” female connector and mounts to standard pipes via its own unique L bracket. This style of mounting makes it a drop-in replacement for existing installations, making it suitable for a wide range of applications. Featuring IP67 compliant weather-proof housing, the antenna has a high degree of protection against dust and water. Its cylindrical radome is made of high impact UV stabilized polycarbonate to protect against rain, ice, snow and salt spray.
Standard or AJ GNSS Antenna (Receiver) – Should I Use GNSS / GPS Anti-Jam Technology?
The standard antenna sees the entire view of sky, equally receiving signals from satellites at the horizon or the zenith and all points in between. However, there is increasing interference in the GNSS L1 band, whether unintentional from other transmitters like communications towers or intentional from illegal “privacy jammers”/GNSS jamming devices. The anti-jamming antenna rejects signals for the lower elevation angles – where most of the GNSS interference comes from – and only receives signals from the higher elevation angles where the satellites are. Of course, this reduces the number of satellites the GNSS receiver will see, but for the timing application, only a few satellites are needed. Moreover, with multi-constellation GNSS receivers, there are an increasing number of satellites available. So you get all the performance in timing accuracy you would get with a standard GNSS antenna plus 20 dB or more of interference rejection.
Model Comparison
| 8230 Antenna | 8230AJ Antenna | 8231 Antenna | 8231AJ Antenna | |
|---|---|---|---|---|
| GNSS Signals Received | GPS/QZSS-L1, GLONASS-L1, Galileo E1, and Beidou B1 | GPS/QZSS-L1, GLONASS-L1, Galileo E1, and Beidou B1 | GPS/QZSS L1/L5, GLONASS G1/G3, Galileo E1/E5a/E5b, BeiDou B1/B2a/B2, and NavIC L5 | GPS/QZSS L1/L2/L5, GLONASS G1/G2/G3, Galileo E1/E5a/E5b, BeiDou B1/B2a/B2, and NavIC L5 |
| Lower Band Frequency | 1164 to 1217 MHz | 1164 to 1254 MHz | ||
| Upper Band Frequency | 1559 to 1606 MHz | 1559 to 1606 MHz | 1559 to 1606 MHz | 1559 to 1606 MHz |
| Temp Range | -40 to 85ºC | -40 to 85ºC | -40 to 85ºC | -40 to 85ºC |
| Gain | 40 dB | 40 dB | 40 dB | 40 dB |
| Connector | N-type, female | N-type, female | N-type, female | N-type, female |
| Diameter | 66.5 mm (Diameter) x 47.5 mm (Height) | 100 mm (Diameter) x 101.5 mm (Height) | 66.5 mm (Diameter) x 47.7 mm (Height) | 100 mm (Diameter) x 156 mm (Height) |
| Weight | 150 g | 370 g | 185 g | 245 g |
| Anti-Jam | No | Yes | No | Yes |
Advantages
Designed for Harsh Environments
Its weather-proof housing is IP67 compliant offering a high degree of protection against dust and water. Its cylindrical radome is made of high impact UV stabilized polycarbonate to protect against rain, ice, snow and salt spray.
An Efficient First Line of Defense Against GNSS Interference
There is increasing interference in the GNSS L1 band, whether unintentional from other transmitters like communications towers or intentional from illegal “privacy jammers”. The AJ antenna rejects signals for the lower elevation angles – where most of the interference comes from – and only receives signals from the higher elevation angles where the satellites are.
Flexible Installation Options
For installations where the antenna cable length exceeds 125 meters we offer a variety of accessories to extend cable lengths including inline pre-amplifiers (Model 8227), fiber optic links and frequency down-up converters.
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FEATURES
- Designed for harsh environments (IP67 rated)
- Drop-in replacement for the Model 8230/8231 Outdoor antenna for use in high interference situations
- Unique conical antenna pattern rejects interference from the horizon
- High out-of-band rejection
- One-year limited warranty
SPECS
- Type: Active
- Gain: 40 dB from internal
- Out-of-Band Rejection:
- < 1500 MHz: > 50 dB
- > 1650 MHz: > 50 dB
- LNA Antenna Pattern: 0 dB at zenith, 15 dB or more rejection at < 30 degrees elevation
- Connector: N type, female
- Recommended Cable: Low Loss LMR-400 Equivalent
- Maximum Cable Length: 125 meters meters (400 ft.)
- Power: 2.5 to 16 Volts, 19 milliamps (typical), powered by receiver
- Enclosure: Radome: High Temperature UV Resistant Polycarbonate.; Base: Zamak White Metal
- Compliance: IP67 and RoHS
- Temperature Range: -40º to +85º C (–40º to +185º F)
- Mounting: L-bracket (included) for vent pipe/pole mounting via hose clamps (included), PVC pipe sold separately
