Evaluation of System Performance of Ultra-Wide Band Jointing in MC Signaling in Correlated Environments

The evaluation of System Performance of UWB (ultra-wide band) jointing in MC (multi-carrier) signaling in correlated environments is presented in the report. The correlated Nakagami-m statistical distribution for the multipath fading model is assumed in this scenario. In fact to establish the model for analyzing in this article is using MC-CDMA (multi-carrier code-division multiple-access) system characterization combined with a UWB scheme. The average BER (bit error rate) is calculated and compared to a special case of previously published results. Studied results from this paper can be implied to approve the system performance for a UWB system combined with a MC-CDMA wireless communication system. It is worth noting that the Nakagami-m distributed fading parameter significantly dominates UWB system performance when it cooperates with MC signaling under a fading environment. Finally, it is worthy of noting that when the SNR (signal-to-noise ratio) at system’s receiver reaches a preset high threshold value, the parameter of power decay ratio effect could be not included.

On Two-Tier Femtocell over Fading Environments

In this paper the system performance of an MC-CDMA (multi-carrier coded-division multiple-access) system operating over single-cell with two-tier femtocell environment is analyzed. Consider two-tier scenario is deployed with a macrocell site in which is being surrounded several femtocells, which are designed to serve a group of subscribers locate in a small coverage area such as small office, home office or a house. The coverage area is typically up to 100 meters in radius. Mostly, the femtocell is applied to serve indoor subscribers, thus, the Rayleigh fading is adopted to characterize the propagation channel. The technique of TH-MC- CDMA (time-hopped multi-carrier coded-division multiple-access) technique is supposed to transmit each symbol alternatively with fair time (slotting)/frequency (coding) for each user in the hotspots (the area around 0th femtocell). The intensity of signals estimated at a mobile unit located in the second tie, i.e., the femtocell coverage area, is an important issue. The contribution of the paper is mainly to evaluate the system performance with both the BER (bit error rate) and OP (outage probability) according to the most important parameters, for example, the activating user number, the hopping number provided by TH-MC-CDMA system and the subcarrier number. Furthermore, the discussion of interference avoidance is also discussed with non-analytically.