The Model AS0087800 GPS Active Antenna is intended for precision timing and navigation applications. It is designed for nominal 5-volt systems, and contains internal voltage regulation, providing consistent performance over an input voltage range from 3.4 Vdc to 5.5 Vdc. This exclusive feature ensures that performance does not degrade with long antenna cables, as can happen with other antennas due to loss in the dc power supply voltage caused by the dc resistance of the antenna cable. While not optimized for 3-volt operation, the Model AS0087800 antenna will operate with dc power down to 2.75 volts, with short antenna cables (typically up to 45 m or 150 ft), delivering acceptable performance with the M12M and many other GPS Engines.
The Active Antenna is designed for long life in challenging environments. The radome is molded of ASA resin, for excellent weatherability. Weather-resistant EPDM O-ring seals are standard. A plated and threaded metal coupling nut provides outstanding corrosion resistance and accepts both 1 in – 14 marine mount and 0.75 in NPT pipe thread. Exposed assembly screws are stainless steel. A separate mounting bracket kit is also offered (p/n AS0044600).
A built-in LED with weatherproof light pipe indicates that the antenna is receiving power, and therefore that the cable is correctly connected to the GPS Receiver. This is another exclusive feature simplifying installation and commissioning.
This antenna has exceptional rejection of interfering signals, low noise figure, and high gain. When used with the iLotus M12M receiver, the nominal attenuation budget is 2 dB to 20 dB, with acceptable performance for cable loss up to 28 dB. With a specified temperature range down to – 55 °C, the Active Antenna is usable in almost any location worldwide.
A separate in-line pre-amplifier (p/n AS0044700) provides 21 dB of gain for applications that require longer antenna cable runs, up to 240 m (800 ft).
|Center Frequency||1575.42 MHz nominal (GNSS L1 band)|
|Gain||LNA: + 38 dB at 1575 MHz, nominal
Antenna element: + 5 dBi (at zenith); -1 dBi (10 ° elevation)
Total, including antenna element: + 43 dBi (at zenith)
|Input Impedance||50 Ω. Compatible with 75 Ω cable.|
|Polarization||Right-hand circular (RHCP)|
|Out of Band Rejection||> 60 dB, for f < 1525 MHz and f > 1625 MHz
> 90 dB, for f < 1500 MHz and f > 1650 MHz
|Noise Figure||LNA: 2.7 dB typical at 1575 MHz
Overall including antenna element: 1.0 dB typical (at zenith)
|Bandwidth||Compatible with GPS L1 C/A signal|
|Group Delay||43 ns, typical|
|Output 3rd Order Intercept||+ 7 dBm, typical, 1575+1576 MHz two-tone test|
|Output 1 dB Compression||+ 1 dBm, typical|
|Power Requirement||3.4 Vdc to 5.5 Vdc, 29 mA nominal; internally regulated
Operational to 2.75 Vdc
|Status Indicator||Bi-Color LED: Green (normal); Orange (power < 3.3 Vdc)|
|Temperature||– 55 °C to + 65 °C, operating|
|Connector||Type F coaxial receptacle, environmentally sealed|
|Enclosure||ASA Thermoplastic with EPDM O-ring seals; meets IP68 of ANSI/EN IEC 60529 and NEMA Types 4X and 6P (when mated to sealed type F connector)|
|EMS (pending||IEC 61000-4-2 ESD; 8 kV contact, 15 kV air discharge
IEC 61000-4-5 1.2/50 µs Lightning Surge; 4 kV/1 kA
|Mounting||Metal coupling nut for 1 in – 14 marine mount and 0.75 in NPT thread
Nut: 1.25 in hex, corrosion-resistant plating
Separate mounting bracket also available (AS0044600)
Mounting hardware is grounded to connector and LNA
|Dimensions||80 mm hex (across flats) x 84 mm tall (3.2 in x 3.3 in), including connector|