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High Gain AntennasHigh-Gain antennas offer the maximum range available for Maxstream Wireless Modems
Each application has different antenna requirements as determined by the desired transmit distance, line of sight conditions and network architecture. There are various options for antennas with trade-offs of cost, size and performance. Factors that affect the performance of the antennas are RF cable length, height of antennas off the ground, obstructions, radiation pattern and gain of the antennas. An RF communications system should be designed such that more than the absolute minimum signal level arrives at the receiver. This will allow some "link margin" in situations where conditions change and the environment degrades the signal. For example: the 9XStream 9600 baud wireless module can decode a signal arriving at the antenna port with a power of -110dBm. Assume that in a certain installation the signal is arriving at a level of -108dBm and the link is working well. If a person walks between the antennas, a tree grows up, tree leaves come out or a heavy rain storm comes along, the signal could be attenuated by as much as 3 to 6dBm. This attenuation might push it over the edge and the link would no longer work. It is good practice to have 6 to 10dB of "link margin" to ensure the link will perform reliably over time. A good understanding of the options and considerations will help any installer build a reliable system. High-Gain Antennas One base station can talk to many remotes using a high-gain omni-directional antenna at the base and lower cost omni antennas on each of the remote units.
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