CIRCULAR POLARIZATION

Seavey Engineering has been a pioneer in the development and manufacturing of innovative, low cost antennas for mobile satellite communications. Antennas are available in a wide range of designs for all moving platforms, such as trucks, railroad cars and locomotives, small boats, ships, private aircraft, automobiles and portable and handheld terminals.

Mobile satellite infrastructure has been expanding to include new high power satellites, LEO and MEO constellations and expanded frequency ranges. Seavey Engineering has kept pace with new requirements by offering an even broader line of user equipment antennas.

We regularly ship at production rates of several thousand antennas per month to support the growing demand for mobile satellite services. The following types of mobile satellite antennas are included in this section:

1.  High Gain, L-band Mast-Type Omnidirectional Antennas

2.  Omnidirectional Antennas: L-band, L-band plus GPS, L/S-bands, L/C-bands, C-band

3.  Portable and Handheld Antennas: L-band, L/S-bands, L/C-bands

4.  Steerable High Gain Antennas: L-band, C-band, Ku-band

Click here for more information on INMARSAT antennas.
Click here for other specialized antennas suitable for mounting on gimbals.

Frequency designations:

1)	L-Band is 1525.0 - 1545.0 MHz (receive) and 1626.5 - 1660.5 MHz (transmit)
2)	L1 GPS is 1575.0 MHz
3)	S-Band is 2.4 - 2.5 GHz
4)	C-Band is 3.7 - 4.2 GHz
5)	Ku-band is 10.95 - 14.5 GHz

1. High Gain Omnidirectional Mast-Type Antennas

Mast antennas are high-gain, omnidirectional helixes and have a variable elevation beam peak range. They are approximately 32 - 35 inches tall and 0.75 inches in diameter. They mount at the base to a customer-supplied spring and/or bumber mount. Manual and motorized remote elevation beam adjustments are available. Specialized mast with a fixed elevation beam peak angle are also available. Peak gain is listed.

Model 9259-800 25 - 70° Coverage Mast	Model 9374-820 Manual RHCP Mast	Model 9537-800 Motorized Mast	Model 9567-800 Manual RHCP Mast

 

Model Number	Frequency Band	Gain dBic	Pattern Type	Features
9259-800	L	9.0	Omni	Manual elevation peaking, RHCP 25° - 70° coverage connector.
9374-820	L	9.0	Omni	Manual elevation peaking, RHCP 25° - 70° coverage connector TNC jack connector on RF cable pigtail.
9537-800	L	9.0	Omni	Manual elevation beam peaking, RHCP, 25° - 70° coverage. TNC connector on antenna.
9567-800	L	8.0	Omni	Manual elevation peaking, RHCP 10° - 30° coverage. TNC connector
9760-800	L	8.5	Omni	Multi-section Mast, 25° - 70° coverage. Disassembles for stowage in an 8 inch length.

2. Omnidirectional Antennas

Model 9007-800 Ruggedized CP Uplink	Model 9651-800 Omni

                       

Model 9520-800 Quadrifilar Helices	Model 9520-810 Two Stacked Quadrifilars	Model 8851-899 L/C/Loran Antenna

               

Model Number	Frequency Band>	Gain dBi(c)	Pattern	Features Type
8835-898	L	4	Omni	Circularly polarized uplink, ruggedized lexan radome. 6.6 inches in diameter, 1/2 inch thick.
9520-800	L	4 - 5	Omni	Helix Antenna pair, one receive , one transmit, each 7.7 inches tall, 1 inch diameter, RHCP, 25° - 70° coverage.
9520-810	L	4 - 5	Omni	Two stacked Helical Antennas, transmit over receive. 12 inches tall, 1 inch diameter, RHCP.
9652-810	L/GPS	4.2	Omni	Helical Antennas, including bandpass filter and downlink LNA. 20° - 70° coverage, 1 inch diameter 7.7 inches long, 3 inch diameter base, RHCP.
9650-801	L/GPS	3.5	Omni	Differential GPS and L-band downlink; 20° - 70° elevation coverage.6.7 inches high, 1.6 inches in diameter.
9650-802	L/GPS	4	Omni	Differential GPS and L-band downlink; 30° - 70° elevation coverage.6.7 inches tall 1.6 inches in diameter.
9650-800	L/GPS	6	Omni	Differential GPS and L-band downlink; 55° - 90° elevation coverage.4.5 inch diameter, 5/8 inches thick. TNC jack connector.
8742-810	L/S	4	Omni	Stacked patch elements. includes integral diplexer, CP uplink and downlink.
8742-860	L/C	4	Omni	Stacked patch elements. includes integral diplexer, CP uplink and downlink.
8956-899	L/S	4	Omni	Vertically Polarized whip with separate diplexer filter. 5 inches long, 3/4 inch diameter, Type N jack RF port.
8835-899	L/Loran	4	Omni	CP uplink with integral Loran C whip and C-band LNB.
8851-898	L/C	4	Omni	CP L-band uplink, Vertical polarized C-band downlink.
8851-899	L/C/Loran	4	Omni	CP L-band uplink, Vertical polarized C-band downlink with integral Loran C whip and C-band LNB.
9007-800	L/C	4	Omni	Ruggedized CP uplink for airborne installations; seperate diplexer filter available.
8829-820	C	4	Omni	Vertical polarized, 20° - 70° elevation coverage, for airborne use. Type N jack RF port.
8852-800	C	4	Omni	Vertical polarized, 20° - 70° elevation coverage, for airborne use. CPR-229 waveguide port.
9356-850	C	5.5	Omni	Vertical polarized, 25° - 65° elevation coverage, for airborne use 2 inches high, 4.5 inch base diameter, sealed radome, Type N jack RF port.
9651-800	C	4	Omni	Vertical polarized, 8° - 25° coverage.

Model 9661-810 LHCP Patch

Model 9661-810 Rear View

Circular polarized omni antennas are used with data link, mobile satellite, base station and signal monitoring equipment.

Radiating elements are turnstiles, bifilar and quadrifilar (QHA) helices.

Seavey Engineering has accomplished pioneering work in modeling, designing and fabricating tens of thousands of circular polarized antennas and holds several patents in this field. The following is a representative product listing. For circular polarized omnis used specifically for mobile satellite work, please see Pages 10-13.

Model 8819-800 VHF RHCP

Model 9386-800 L-Band RHCP

Model 9438-800 L-Band RHCP

Model 9429-810 L-Band LHCP

Model 9508-800 S-band RHCP	Model 9806-800 S-Band LHCP	Model 9303-800 C-Band LHCP
Model 9234-800 S-band RHCP	Model 9429-840 C-Band LHCP	Model 9510-800 X-band RHCP