Fading Channel Characterization over Frequency Hopping Spread Spectrum
نویسندگان
چکیده
The number of radio systems operating in the 2.4 GHz band is rising as a result of increased usage of wireless technologies. Since such devices interfere with one another, satisfactory co-existence becomes important. Several techniques serve to reduce the interference. Included among these are frequency hopping (FH) and power control. From the simulation results it can be seen that frequency hopping provides a significant improvement in the channel coherence time. At Doppler frequencies exceeding a certain level hopping provides a small improvement. While at lower Doppler frequencies, the effect of FH dominate the multipath fading. As a result, the hopped systems provide a coherence time which is largely independent of Doppler frequency.
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