Metamaterials vs. Phased Array
A new wave of flat panel antenna technology is emerging for satellite communications. These antennas have removed mechanical components, relying on software and electronics for steering making them available for mobile platforms like cars, boats, planes and more.
But not all flat panel antennas are the same. Kymeta’s metamaterials-based antenna is the first of its kind, and bears significant differences to other phased array flat panel antennas in the market today.
What it’s made of:
Phased array antennas rely on microprocessor technology and software algorithms for combining signals received by numerous antenna elements . In most cases, each antenna “panel” is populated with a collection of independent “patch” antennas and corresponding beam forming microchips. Think of it like one big antenna made up of multiple smaller antennas whose data must be processed and combined.
Kymeta mTenna™ technology is built using a metamaterials toolset, which permits more elements and is a much more efficient way of creating a flat-panel antenna. As a technical discipline, metamaterials isn’t a specific thing, but a toolset similar to nanotechnology. The metamaterial in mTenna technology is a metasurface and that metasurface is a glass structure similar to a liquid crystal display (LCD).
Instead of reflecting microwaves (i.e., dish) or creating thousands of separate signals (i.e., phased array), Kymeta uses a thin structure with tunable metamaterial elements to create a holographic beam that can transmit and receive satellite signals.
The satellite antenna portion of the Kymeta KyWay™ terminal (mTennaU7 ASM) has thousands of individual radiating elements that act collectively on a single signal, like television pixels, to create the holographic beam. By changing the pattern of activated elements, the antenna beam can be pointed in different directions with no moving parts. Kymeta offers the only commercially-available, electronically-scanning satellite antennas and terminals and the technology is backed by U.S. and international patents and licenses.
How it works: power and performance:
An active phased array antenna requires “phase shifters” and amplifiers to adjust the phase and/or amplitude of each antenna element . In most phased array antennas, power amplifiers are combined with phase shifters to compensate for loss in active phase shifting, which leads to greater power consumption by the antenna.
The elements in a phased array are spaced farther apart, which means they need active electronic components to create the necessary phase and amplitude distribution to form a beam. The active electronic components draw more power and easily overheat, requiring a heating and cooling system that makes them thicker, more expensive and big power consumers (kilowatts instead of watts).
Because of this, manufacturers must minimize the number of elements used, which leads to increased beam width in one or more dimensions and reduced scanning ability. Mechanical positioners are frequently used with phased arrays to spin panels into position, obtain full coverage with limited scanning and ensures the beam doesn’t interfere with other satellites.
Metamaterials enable Kymeta’s antenna to provide the dynamic, electronic beam-steering performance of a phased array, without the need for expensive and power-hungry phase shifters, related amplifiers and other components. Utilizing metamaterials design principles, Kymeta’s approach dramatically increases the density of antenna elements in mTenna as compared to a phased array. This means that phase and amplitude can be controlled simply by activating or deactivating antenna elements. The antenna, therefore, is “passive” because it doesn’t need active phase shifters, and the liquid crystal and glass used to manufacture it don’t have active RF components.
Kymeta’s antenna is capable of software-controlled/dynamically-switchable polarization, which isn’t defined by the element polarization (as seen in phased array), but rather a software-generated radiation pattern..
The mTenna technology doesn’t have power amplifiers that create excess heat, and therefore doesn’t require a cooling system like traditional phased arrays. This means the antenna consumes only a few hundred watts of power – as opposed to phased array antennas of equivalent size that typically consume more than a thousand watts.