subject: Omnidirectional Antenna Capabilities Featuring The Oscar 1 Bracket Mounted Omnidirectional Antenna [print this page] Omnidirectional antennas are sometimes referred to as 'omnis'. Omnidirectional antennas are fantastic when coverage is required in all directions (horizontally) from the antenna with varying degrees of vertical coverage.
Omnidirectional antennas are perhaps the most commonly known of these types of antenna, and can be found on automobiles, cordless phones, portable radios and many older-style cell phones.
These antennas tend to have reasonably low gain due to the fact that the beam pattern, or the direction in which they can transmit and receive radio waves, is not focused. Omnidirectional antennas radiate equal power in all directions in a horizontal plane parallel to the earth's surface, providing a 360 degree horizontal radiation pattern, which is often described as looking like a doughnut. Because the signal radiates out in a circle from the antenna, this enables a device to the left of the antenna to receive the same signal as a device the same distance away on the right.
Although omnidirectional antennas are fantastic for delivering signal evenly on its horizontal plane, they have no preferred direction and cannot differentiate between a wanted and an unwanted signal. However, in applications where higher gain is not the primary criterion and it isn't necessary to constantly position the antenna so that it is aligned with the direction of the signal, an omni is perfect for its purpose. Higher-gain omnidirectional antennas can also be built. "Higher gain" in this case means that the antenna radiates less energy at higher and lower elevation angles and more in the horizontal directions.
For receiving, omnidirectional antennas are often recommended for indoor use because the RF signal is reflected off of the walls and ceiling. Most wireless routers come with omnidirectional antennas. This is because they provide wider coverage, making it possible to form circular overlapping cells from multiple access points located throughout the building. Providing there are no major sources of interference, such as brick or concrete walls, metal surfaces or sources of radio interference, such as microwave ovens and garage door openers.
The Oscar 1 is a wall mounted antenna that is designed to offer high performance in an omnidirectional pattern when operating on GSM/GPRS networks as well as at 3G frequencies.
The Oscar 1 is ruggedly constructed with Black ABS plastic over the radiating element and with a lightweight yet durable aluminium mounting bracket, the OSCAR 1 is designed for outdoor use to improve cellular signal strength reception and to provide an excellent quality product for network dependent and unmanned applications such as base stations or remote monitoring.
With a gain of up to 3.5dBi, this antenna is supplied with 5 metres cable (different lengths as required) allowing routing and maximum elevation to increase line of site communications. The standard product is terminated with an FME female with other options available on request.
