NEC Develops One of the World's Smallest Antennas Using Metamaterial Components for Improving Wireless Module Communications Performance- Newly developed antenna optimal for sensors used in building M2M networks -

*** For immediate use March 19, 2012


Tokyo, March 19, 2012 - NEC Corporation (NEC; TSE: 6701) announced today the development of one of the world's smallest antennas that can be installed in short-range wireless modules embedded in sensors and other devices for building Machine-to-Machine (M2M) networks.

This newly developed compact antenna uses a split-ring resonator (*1), a type of metamaterial (*2) component. By stacking split-ring resonators in multiple layers, NEC has created one of the world's smallest antenna elements maintaining a sufficient amount of radio-wave radiation. Optimizing the shape of the resonator has made it possible to not only suppress fluctuations in antenna performance when embedding the wireless modules in devices but also achieve radio emission characteristics with sensitivity in all directions.

Installation of this antenna in short-range wireless modules such as ZigBee and Bluetooth-the key components of M2M networks-makes it possible to extend the distance between the components and to maintain communication without dependency on their orientations. This then enables the realization of M2M networks that are readily connected and are highly stable.

The following are some of the key features of this newly developed technology.

1. Realization of one of the world's smallest antennas
   The split-ring resonators are formed on printed circuit boards in multiple layers. The stacked structure of the resonators has enhanced capacitance for the antenna in comparison with single-layer resonators and maintains highly efficient radio-wave radiation, which has resulted in an antenna that is one of the world's smallest.


2. Realization of an antenna capable of suppressing fluctuations in performance when embedded in a device
   Optimizing the shapes of the split-ring resonators makes it possible to concentrate the current around the resonators, thereby suppressing fluctuations in antenna performance that occur in conventional antennas as a result of current leakage into structures in substrates and devices, as well as achieving stable transmission and reception performance.


3. Realization of an antenna with high sensitivity in all directions
   Optimal combination of two current components that flow on split-ring resonators enables the emission of radio waves in all directions. This eliminates the bias that exists in the emission direction of radio waves with conventional antennas, as well as enables stable communications regardless of the direction in which the antenna is facing.

Notes

(*1) Split-ring resonator:
A split-ring resonator is a type of metamaterial component. This C-shaped resonator is composed of partially split metallic rings and exhibits the properties of a magnetic material.

(*2) Metamaterial:
Metamaterials are artificial materials engineered to have properties not found in nature through periodic placement of building blocks. Metamaterials consist of numerous conductive or dielectric element arrays in a shorter period much less than the wavelength of electromagnetic waves.

(*3) Home Energy Management System (HEMS):
HEMS is a system that displays the power consumption of household appliances and remotely controls their operation.

NEC Press Contacts (Japan)

Takehiko Kato
NEC Corporation
+81-3-3798-6511
E-mail:t-kato@cj.jp.nec.com

Joseph Jasper
NEC Corporation
+81-3-3798-6511
E-mail:j-jasper@ax.jp.nec.com