本帖最后由 payne_pan 于 2016-4-27 14:33 编辑
我用的flysky+ er9x + djt + d8r, 飞出100多米，rssi就降得比较厉害， 但还没有拉锯测试。The RSSI value is what the receiver is reporting. The normal (default) values for this being considered low are 45 for a warning and 42 for critical.
有文档说明 1m的时候 rssi是110， 之后距离每增加一倍 rssi -6The received signal strength (RSSI) is actually not an absolute value like voltage or temperature but a number that indicates the ratio of the signal to some initial "good" value. It is in dB and is the same measuring system used for audio levels. For a fixed single system like the FrSky system we can treat the RSSI as an absolute value of strength since the "good" value is already chosen and fixed. The only unusual thing is that dB is a logarithmic measure, not linear. What this means is that any increase of 6 means the signal has doubled in strength. So a change of +12 in the RSSSI means the signal has increased in power by 4 times, by +18 means the signal has increased in power by 8 times, by +24 means the signal has increased in power by 16 times. Conversely if the RSSI goes down by -18 the signal power is 1/8 what it was. For the FrSky system the RSSI should read about 110 at 1m and every time you double the distance between the transmitter and receiver, the RSSI level should drop by 6. That's why it goes down quickly at first then less and less as the model flies away since you have to double the existing distance each time to get 6 lower. Theoretically at about 100 meters you should get an RSSI value of about 70 in ideal conditions.
跟我用的凤凰433不一样
凤凰433作者说 rssi为0，才失控。
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发表于 2016-4-25 10:55
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