Enhanced Performance of Fading Dispersive Channel Using Dynamic Frequency Hopping(DFH)

techniques are examined to overcome the performance degradation caused by the channel dispersion using slow frequency hopping (SFH) with dynamic frequency hopping (DFH) pattern adaptation. In DFH systems, the frequency slots are selected by continuous quality monitoring of all frequencies available in a system and modification of hopping patterns for each individual link based on replacing slots which its signal to interference ratio (SIR) measurement is below a required threshold. Simulation results will show the improvements in BER obtained by DFH in comparison with matched frequency hopping (MFH), random frequency hopping (RFH) and multi-carrier code division multiple access (MC-CDMA) in multipath slowly fading dispersive channels using a generalized bandpass two-path transfer function model, and will show the improvement obtained according to the threshold selection.

Authors:

• Walid M. Saad

Keywords:

• code division multiple access (CDMA)
• dynamic channel allocation (DCA)
• dynamic channel assignment
• frequency hopping
• matched frequency hopping (MFH).

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