Phased Array Antenna

At present, phased array antennas on the market are generally classified into three categories:

The first type: horn array phased array

The second type: microstrip phased array

The third type:liquid crystal phased array

The basic principle:

After the initial orientation of electromagnetic liquid crystal metamaterials, the liquid crystal molecules can be arranged according to certain rules. As shown in the following figure, by applying a bias voltage to the liquid crystal metamaterial layer and changing the orientation of liquid crystal molecules, the permittivity parallel to the long axis of liquid crystal molecules and the permittivity perpendicular to the long axis of liquid crystal molecules will be different, thus forming the equivalent permittivity εr of liquid crystal metamaterial in a certain range, that is, ∆ε=εr‖-? r? When it is no longer zero, it shows dielectric anisotropy. Using this property of liquid crystal can realize the continuous regulation of electromagnetic wave phase and other characteristics.

Comparative analysis with CMOS low cost phased array antenna technology

Cheaper silicon-based CMOS process is used to replace expensive GaAs and GaN processes, sacrificing part of T/R component performance (small single-channel power and low efficiency) in exchange for a relative reduction in cost, and the antenna integration is high, enabling the phased array antenna beam to have high precision and fast scanning capabilities. However, it is still based on the RF chip integrated circuit production line and process, the production is more difficult, the RF plate, the manufacturing process, etc., are subject to foreign countries, mass production and cost reduction is still difficult for a long time, and its large-scale application is limited by cost, size, weight, power consumption, and system complexity.

Manufacturer	Kymeta	Alcan System
Operating Frequency	Tx:13.75-14.5Ghz	Tx:27.5-30Ghz
	Rx:10.7-12.75Ghz	Rx:17.7-20.2Ghz
Pol	Linear	Circular
EIRP	45.5 dBW @90°（20W BUC）	44.9dBW@90°（6W BUC）
G/T	11.25dB/K@90°	≥10.8 dB/K@90
First side lobe		≤-17
Scaning Range	AZ:0-360° Off-axis angle >±75°	AZ:0-360° Off-axis angle >±55°
Weight	32kg	18kg
Working temperature	-40°~70°	-20°~55°
Demension	90*90*14cm	55*99.5*90

Electromagnetic control of liquid crystal metamaterial phased array antenna not only has excellent performance indicators, but also can use the existing liquid crystal display panel production line to carry out mass production, so it has a good low-cost industrialization basis, and its structure is high consistency, panel structure is stable, avoid the traditional T/R components of the complicated debugging process, shorten the product production cycle. There is potential for large-scale cost reduction in the future, which is expected to bring the product price down to an acceptable level for consumers。

Liquid crystal phased array and low cost T/R component phased array are the two main technical routes at present. From the perspective of cost and large-scale production, electromagnetic control of liquid crystal metamaterial phased array antenna has more advantages, which is not only expected to solve the bottleneck of the industrialization of core devices in satellite Internet, 5G and other fields, but also lead technological innovation and synchronically follow up international cutting-edge technologies.