Implementation of experimental equipment with Wideband Non-Contiguous OFDM

Evaluation of influence by simultaneous reception of other radio systems in wideband NC-OFDM

“…Guard Bands [8] concluded that the degradation of the transmission bit error ratio (BER) performance in an environment, where plural RF-units were closely allocated, was less than 0.5dB, compared to an environment in which a standalone RF-unit is employed. This result also showed that the ICI effect between the RF-units was not so critical since a common reference oscillator was employed for accurate frequency synchronization.…”

“…As one practical implementation method to support such wider bandwidths, we employ plural, divided, and small RF-units. With the scheme, the above hardware requirements are relaxed, offering the possibility of hardware increases[8]. The experimental equipment employs four RF-units.…”

Efficiency Enhancement Based on Allocating Bizarre Peaks

“…V-BLAST is used for increasing the overall throughput expressed in terms of bits/symbol, while applying the IFFT to generate the OFDM symbols [2,15]. As a consequence for the coherent addition after the IFFT, a huge peak value may appear [1][2][3][4][5][6][7][8][9][10][11][12].…”

“…This is in order to achieve a promising data rates either for the downlinks or the uplinks physical transmissions, especially after the rapid growth in using the mobile phone applications [1,2]. Along the last decades, the researchers got from the benefits of OFDM technology and are adopted widely in the recent wireless communications technologies; especially in the wide band systems and standards, where the Mobile data traffic expected to increase by 11 times by 2018 [3,4]. However, the Peak-to-Average Power ratio problem is considered as one of the major drawbacks that limits the efficiency of OFDM technology.…”

Effectiveness evaluation of Combined Time Windowing with narrow frequency bandwidth for WNC-OFDM

“…under 1 GHz) frequency band is suitable for mobile data communications because of its radio propagation characteristic, but there are no available wide frequency bands for new systems. To obtain usable frequency bands in this situation, we focus on Wideband Non-Contiguous Orthogonal Frequency Division Multiplexing (WNC-OFDM) technology [2]. For mobile data communications, WNC-OFDM gathers small pieces of narrow bandwidths (narrowbands) of unused frequency bands in wideband spectrum.…”