Glossary · 31 terms

The words on the data sheet, explained

Every term below is used the way this catalogue uses it — so a figure on a product page and a word here mean the same thing. Where a definition attaches to a specific product or guide, the link is in the entry.

Systems

ACU (antenna control unit): The controller between the antenna and everything downstream: it powers the antenna, holds the satellite parameters, and hands the L-band signal to the receiver. Two versions are documented — Basic, which is configured manually, and Advanced, which adds webpage configuration, cloud monitoring and route tracking.; Antenna control unit →Basic vs Advanced ACU →
TVRO: Television Receive Only. A satellite television system that receives and never transmits: an outdoor antenna tracks the satellite, outputs L-band, and everything downstream decodes and distributes it. Because there is no uplink, a TVRO terminal needs no licence to transmit and no airtime contract — the contrast with VSAT, which carries data both ways.; Maritime IPTV & CATV system →
VSAT: Very Small Aperture Terminal — a two-way satellite data terminal, as opposed to a receive-only TVRO. It carries internet, voice and video, so it needs a service contract with a satellite operator. On a vessel the antenna is stabilized on the move, and the band (Ka, Ku or C) is chosen by the route and the operator rather than by the hardware.; Marine VSAT terminal →4G/5G vs VSAT vs microwave →

Hardware

Radome: The weatherproof cover over the dish. Its diameter is what the catalogue quotes as the model size — 33 to 75 cm on the V Series, 64 to 105 cm on the X Series — and it drives weight, wind load and the mounting structure long before it drives performance. A radome is not cosmetic: it is the reason the antenna survives salt and green water.; Explosion-proof cameras →

Link budget

EIRP: Effective Isotropic Radiated Power — how strong the satellite signal is where you are. Minimum EIRP is the weakest signal an antenna can work with, so a lower number is better: the TVROVSAT range runs from 50 dBW on the 33 cm model down to 41 dBW on the 105 cm one. Choose the antenna by the weakest footprint on your route, not the strongest.; V Series →X Series →
Ku, Ka and C band: Three satellite frequency bands with different trade-offs. Ku (10.7–12.75 GHz on the V and X Series) is the widest choice for mixed routes; Ka (18.2–19.2 and 19.2–20.2 GHz, listed as a dual-band option on the V Series) buys capacity but is rain-fade sensitive and footprint-specific; C band holds up better in heavy rain and at low elevation, which is why it stays relevant in the tropics. On the VSAT terminal all three are listed, with the service set fixed by the operator.; 4G/5G vs VSAT vs microwave →
Polarization (linear and circular): The orientation of the signal. A linearly polarized satellite needs the feed aligned to its plane — which is what skew does — while circular polarization does not. The catalogue lists linear or circular on both antenna families, with the Ka-band feed specified as linear or circular.; Automatic skew →
Satellite footprint: The area on the earth a satellite illuminates with usable signal strength, usually drawn as contours of dBW. A route that leaves the footprint loses the link no matter how large the antenna; a route that stays at the edge needs a lower minimum EIRP. Footprints change when operators re-point or replace satellites, which is why the antenna margin matters more than the peak figure.; How to size a TVRO antenna →

Stabilization

2-axis and 3-axis stabilization: How many mechanical axes keep the dish pointed while the ship moves. A 2-axis platform drives elevation and azimuth and relies on automatic skew for polarization; a 3-axis platform adds cross-level so the assembly stays square to the satellite during sustained heel. More axes mean more weight and a heavier mounting structure.; 2-axis vs 3-axis →
Automatic skew: Rotation of the feed around the dish axis so its polarization plane stays aligned with the satellite as the vessel changes heading. Without it, a linearly polarized signal loses part of its level as the ship turns, which shows up as a slow fade rather than a lost lock. Both TVROVSAT families include it.; 2-axis vs 3-axis →
Azimuth and elevation: The two coordinates that point at a satellite: azimuth is the compass direction, elevation is the angle above the horizon. The V Series covers 0°–90° elevation, the X Series −5°–115°; both cover 0°–690° azimuth. The negative elevation range matters when the antenna is mounted low and the satellite sits near the horizon.; 2-axis vs 3-axis →
Cross-level range: The heel angle a 3-axis mount can compensate while keeping the dish square to the satellite — ±35° on the X Series. It is the axis a 2-axis platform does not have, and it is the difference between tracking a rolling hull and tracking a hull that stays heeled.; X Series →
Ship motion envelope: The roll, pitch and yaw the antenna is specified to follow while tracking — on both TVROVSAT families, roll ±25°, pitch ±15° and yaw ±8° at a 6-second period. It is a specification, not a guarantee: beyond that envelope the antenna cannot keep the satellite in view, which is why the vessel type matters as much as the dish size.; Which antenna for which vessel →
Tracking rate: How fast the platform can follow a change in pointing, quoted in degrees per second — above 90°/s across the TVROVSAT range. It matters during a fast yaw, when the vessel turns and the look angle to the satellite changes quickly. Ship motion is quoted separately as roll, pitch and yaw at a period.; V Series data sheet →

Distribution

CATV (on board): Community antenna television: the satellite feed is decoded and re-modulated onto the vessel's coaxial network, so any television with a matching tuner can watch it. The documented multi-room configuration carries up to 58 channels by putting different channel sets on the two polarizations. It is the cheapest route on a vessel that already has coax in the walls.; CATV vs IPTV →
Headend: The rack that turns sources into a distributable signal — in a CATV system the decode-and-modulate chain, in an IPTV system the encoders and streaming server. Everything upstream of the cabins and downstream of the antenna lives here, which makes it the part of the system that is specified once and then forgotten until a channel changes.; Maritime IPTV & CATV system →
IPTV (on board): Television delivered as streams over the ship LAN rather than as a modulated RF signal. Because everything is a stream, satellite TV, CCTV, video on demand and in-house programming can share one menu; the documented feature set includes menu customization, user management, a boot screen, information insertion and catch-up playback.; CATV vs IPTV →
Multiswitch: The rack device that routes selected polarizations from the receiver chain to the receivers, so different cabins or decoders can use different transponders. In a dual-antenna installation it is the part that decides which dish feeds which receiver — which is why the wiring diagram usually matters more than the data sheet on a two-dish vessel.; Maritime IPTV & CATV system →

Hazardous area

Ex d (flameproof enclosure): An enclosure built so that an internal ignition is contained and the hot gas is cooled before it escapes — the "d" part of the marking. On these cameras the published string reads Ex d IIC T6 Gb: equipment group II, gas group IIC (the most demanding), temperature class T6 (surface temperature limit), equipment protection level Gb. Ask for the certificate against your flag state rather than relying on the string alone.; Hazardous-area cameras →
Ex tD (dust protection): Protection by enclosure for combustible dust — the second half of the published marking, Ex tD A21. It appears alongside the gas marking because a cargo hold or a coal-handling area is a dust hazard rather than a gas one. A camera marked for gas is not automatically suitable for dust; the full string is what matters.; Hazardous-area cameras →
IP rating (IP66 and IP68): Ingress protection against solids and water. IP66 is dust-tight and resistant to powerful jets; IP68 adds continuous immersion at a stated depth and time. On a vessel the practical difference is where the unit may be mounted: IP68 where the deck floods, IP66 under a structure that sees spray but not standing water.; Dome cameras (IP66 vs IP68) →

Cameras

Fisheye and dewarping: A lens that images a full hemisphere — 180° × 180° at 1.05 mm in this range — producing a circular image that software unwraps into a flat view. Dewarp modes (180°, 360°, PTZ) turn one ceiling-mounted unit into an all-round view. The trade is resolution per metre: a fisheye shows the whole room, not a face in it.; Fisheye cameras →
IR illuminator: Infrared lighting built into the camera so it can see in the dark, quoted as a distance — 10 m on the fisheye, 30 m on the fixed types A and B, 50 m on Type C and 80 m on Type D. The figure is a working distance in clear air, not a definition of image quality at that range.; Fixed IR cameras →
NVR: Network video recorder — the box that records the camera streams and gives operators presets and playback. In a PTZ specification the NVR is not an accessory: it is the control path and the dewarping client, so it has to be chosen before the cameras are ordered.; PTZ cameras →
PoE: Power over Ethernet — supply and data on one cable, which removes the need for a local mains feed at the camera. On a hazardous-area installation the benefit is one cable entry instead of two, and one less gland to seal. Check the per-model table: not every unit in the range lists the same supply options.; Hazardous-area cameras →
PTZ: Pan, tilt, zoom — a camera that can be driven to look somewhere rather than bolted to a view. On deck the wiper matters as much as the axes: a PTZ pointed into weather collects salt on the window, and the wiper is what keeps the picture usable. All four models in the range are 360° continuous pan with 20× optical zoom and a wiper.; PTZ cameras →
Wiper and lens washer: Two different jobs. A wiper clears water from the window; a washer sprays water onto dried salt and soot before the wiper sweeps. Cameras with wipers are listed as such across the range; the washer is a separate 5 L tank with a vacuum pump, 27 PSI and a 5 m hose, fitted where fouling is heavy.; Lens washer tank →

Connectivity

LTE and 5G NR: The shore mobile standards a marine cellular antenna receives: FDD and TDD LTE, WCDMA/HSDPA/HSUPA/HSPA+, TD-SCDMA and NR/EN-DC in the documented unit. On board, "5G NR" is about the radio link to the base station; what the crew experiences is still governed by the carrier's backhaul and the distance to shore.; 4G/5G marine antenna →
Micro-cell coverage: A small indoor radio layer that re-broadcasts the shore network inside the ship, so the signal reaches the engine room, workshop and control room where the steel hull blocks it. Because it is a local cell, it also carries traffic off the shore macro network — which is why the documented benefit is both better call quality and a higher connection rate.; Onboard mobile coverage →
Point-to-point and mesh: Two ways to arrange a microwave link. Point-to-point joins one ship to one shore station; mesh lets two mobile stations form a link with each other on the move. The documented unit covers both, at up to 100 km and 200–300 Mbps, without satellite airtime.; Microwave auto-tracking antenna →
Priority switching: The handover policy between a shore cellular link and a satellite link: use the cheaper shore link while it has coverage, fall back to satellite when it does not. It is documented for the 4G/5G antenna with VSAT, and it is a configuration decision — the hardware only does what the policy tells it.; 4G/5G vs VSAT vs microwave →

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