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Longer-Range Directional Antennas

Although most indoor systems do not require high-gain directional antennas, in some circumstances you might use a 10- or 13-dBi Yagi indoors to cover areas such as long corridors or long runs between high shelving (such as in a do-it-yourself homeowners' warehouse). In these cases, the Yagi can provide the necessary long-range, narrow-focused beams.

For longer outdoor links, a parabolic dish antenna might be required. For both the Yagi and parabolic dish antennas, when mounting, be sure to not only consider the horizontal beam width, but also the vertical beam width. Most dish antennas are provided with adjustments for vertical alignments, and some Yagi antennas have optional mounts to permit vertical alignment as well.

Figure B-10 shows a Cisco 13.5-dBi Yagi antenna. This might look similar to antennas you have seen from Telex, Proxim, and others, because it is sold by many different manufacturers as an OEM product.

Table B-8 lists the specifications for the Telex 13.5-dBi Yagi antenna.

Figure B-11 shows a Cisco 21-dBi solid parabolic dish antenna. As with the Yagi, this particular antenna is sold by many different vendors as an OEM product.

Table B-9 lists the specification for the 21-dBi dish antenna.