subject: Understanding Embedded Antennas And The Advantages And Disadvantages Embedded Antennas Bring [print this page] Internal antennas, although not new to our industry, are being driven by the design engineers. Several companies are focusing on developing and commercializing embedded antennas for the next generation of wireless devices. The last generation, especially patch antennas, has had limited success due to the limitations of performance, there is a problem in that such a conventional embedded antenna has a narrow bandwidth. (designers have demanded whip-like performance). Recent R&D companies, such as RangeStar, have now eliminated this performance issue by offering both directional and omni-directional embedded antennas with 0 to 5 dBi gain, VSWR of less than 2:1, and a significant cost reduction.
Each example of antenna brings its own advantages and disadvantages to the market and this need to be weighed up prior to selection. In practice, an external antenna generally performs better than an internal antenna. The space for incorporating the embedded antennas also increases according to the size increase of the antenna. Therefore, the embedded antennas occupy a significant amount of the inner space of the cellular phone. Consequently unless there is a strict requirement in a specification of requirements that an embedded antenna has to be used - such as a vandal resistant or high IP rated environment, increasing the likelihood of good wireless communications has to be the number one priority.
Through advanced technology and flexible designs, manufacturers of embedded antennas help empower device designers to create a full range of consumer electronics with wireless connectivity. Embedded antennas are found in a wide range of mobile platforms including slim mobile handsets, smartphones, netbook computers, PC cards including Express34, personal media players, ultra-mobile PCs, and wireless earphones. Embedded antennas are popular for mobile devices because they offer a cost-effective solution and a device without an external antenna is more desirable to consumers.
Embedded antennas in most mobile devices cannot take polarization into consideration as they often most continuously move in different planes versus the device they are communicating with. The standard toroid power output pattern of embedded antennas with further attenuation of the surrounding materials creates nulls in the antennas output which are eliminated by the near spherical power output pattern.
There is no upper boundary to the frequencies that embedded antennas can support. Ultra-wideband (UWB) applications operate at 3 to 10 GHz, which is currently the maximum of what is relevant to commercial applications.
Today's wireless engineer must balance the cost vs. performance equation. Embedded antennas, offered as an SMD or perpendicular mount, provide the performance at 2.4 GHz, the ISM operating frequency which is necessary to be compliant to the Bluetooth specification version 1.0.
The embedded antenna finally has come of age. With a renewed focus on the advancement of this basic RF technology, antennas, new and more efficient embedded antennas will be available.
