Parasitic Element Coupling Device

These devices contribute to wider bandwidth antenna characteristics and more compact size.
For example, in the case of antennas for applications that require a wide frequency bandwidth, such as Wi-Fi 6E, Wi-Fi 7, and cellular communication, these devices give the antenna wider bandwidth and improve its efficiency, meaning that the antenna can made smaller.

Product overview
Product Lineup
Datasheet
Example applications
Usage examples
Inquiries

Product overview

The parasitic element coupling device establishes a strong coupling between a feeding antenna and a parasitic element (parasitic antenna), enabling a wider bandwidth and greater antenna efficiency. Using such a device makes it possible to obtain favorable antenna characteristics even with compact antennas where it is difficult to use a parasitic element.
Murata Manufacturing’s proprietary multilayer technology was used to place the transformer coil in close proximity, which achieves a strong electromagnetic field coupling without the use of a magnetic substance. This made it possible to develop these devices that contribute to improved antenna characteristics and a more compact size.

Fig. 1: Illustration of parasitic element coupling device implementation and its effects (wider bandwidth and improved antenna efficiency)

Fig. 2: Illustration of internal structure and exterior view

Advantage 1 Wider antenna bandwidth and improved antenna efficiency

Using a parasitic element coupling device in the antenna block makes wider bandwidth possible.
Fig. 3 is a comparison of simulated antenna characteristics (return loss) and antenna efficiency when a parasitic element coupling device is used and when no such device is used. A strong electromagnetic coupling is established between the parasitic element and the feeding antenna, adding the antenna resonance of the parasitic element and achieving both wider bandwidth and improved antenna efficiency.

No parasitic element coupling device used.

Parasitic element coupling device used.

Fig. 3: Return loss over wider bandwidth and improved antenna efficiency due to parasitic element coupling device (simulation)

Advantage 2 More compact antennas

A parasitic element coupling device effectively increases the antenna efficiency, making it possible to use a smaller antenna.
Generally speaking, if a feeding antenna and parasitic element are used together with a weak electromagnetic coupling, when the antenna is miniaturized, the coupling between the parasitic element and the ground will be stronger, further weakening the coupling with the feeding antenna. This reduces the functionality of the parasitic element as an antenna and degrades the efficiency of the antenna.
Since a parasitic element coupling device establishes a strong electromagnetic coupling between the parasitic element and the feeding antenna, one can expect good antenna efficiency even when using a compact antenna.

No parasitic element coupling device used.

Parasitic element coupling device used.

Fig. 4: Smaller antenna size and improved antenna efficiency due to parasitic element coupling device (simulation)

Advantage 3 Reduction in effects of cable loss

Using a parasitic element coupling device to establish a strong electromagnetic coupling between the parasitic element and the feeding antenna improves the matching characteristics.
This prevents multipath reflection between the antenna and RF modules and makes it possible to reduce the effects of insertion loss when using a long cable.

Evaluation conditions

[Evaluation board]

[Antenna pattern]

No parasitic element coupling device used.

Parasitic element coupling device used.

[Condition-1]

Without cable (50Ω Transmission Line)

[Condition-2]

700mm Coaxial cable

Evaluation results

Without cable
S-parameter

700mm Coaxial cable
S-parameter

Product Lineup

A lineup of products is available for use in various regions.

Part Number	Type	Insertion loss (typ.)^*1		DCR (Max)
Part Number	Type	Measurement frequency	IL (dB)	(Ω)
LXPC15AHA1-001	For Middle/High Band	1.7GHz	0.1	0.2
LXPC15AHR1-002	For Middle/High Band (Mirror type of -001)	1.7GHz	0.1	0.2
LXPC15ALA1-003	For Low Band	1.7GHz	0.1	0.4
LXPC15ALR1-005	For Low Band (Mirror type of -003)	1.7GHz	0.1	0.4
LXPC15AUA1-008	For Sub6G Band	3.3GHz	0.2	0.3
LXPC15AUR1-009	For Sub6G Band (Mirror type of -008)	3.3GHz	0.2	0.3
LXPC15AWA1-012	For Wi-Fi 6E	6GHz	0.35	0.3
LXPC15AWR1-013	For Wi-Fi 6E (Mirror type of -012)	6GHz	0.35	0.3

*1Measurements were performed with port 3 and port 4 open and port 1 and port 2 connected, and the data incorporates correction for port 2 reflection loss.

Datasheet

Download datasheet

A datasheet common to the entire series and listing product characteristics, reliability data, packing specifications, etc., is available for download.

Example applications

Parasitic element coupling devices can be used in a variety of products that employ antennas, including notebook PCs and smartphones.

Notebook PC
Smartphone / Cellular phone
Tablet PC
xR (AR, VR, etc.)
Digital cameras
Game consoles
Television
Wi-Fi Router

Usage examples

Parasitic element coupling devices are used in smartphones and notebook PCs.

Smartphone usage example

This is a usage example in a smartphone employing a frame antenna.
Parasitic elements are mounted on the board, and wider bandwidth is achieved by coupling them using parasitic coupling devices.

Circuit diagram

Inquiries

Please feel free to contact us via the links below with questions or inquiries regarding samples, estimates, etc.

Avoiding Counterfeit Products

PageTOP