Bit error rate reduction for circular ultrawideband antenna by dynamic differential evolution

Abstract

The dynamic differential evolution (DDE) is used to synthesize the radiation pattern of the directional circular arc array to minimize the bit error rate (BER) performance in indoor ultrawideband (UWB) communication system. Using the impulse response of multipath channel, the BER performance of the synthesized antenna pattern on binary pulse amplitude modulation system can be calculated. Based on the topography of the circular antenna array and the BER formula, the array pattern synthesis problem can be reformulated into an optimization problem and solved by the DDE algorithm. The novelties of our approach are not only choosing BER as the object function instead of sidelobe level of the antenna pattern but also considering the antenna feed length effect of each array element. The strong point of the DDE algorithm is that it can find out the solution even if the performance index cannot be formulated by simple equations. Simulation results show that the synthesized antenna array pattern is effective to focus maximum gain to the line of site path which scales as the number of array elements. In other words, the receiver can increase the received signal energy to noise ratio. The synthesized array pattern also can mitigate severe multipath fading in complex propagation environment. As a result, the BER can be reduced substantially in indoor UWB communication system. V C 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE 22:260-271, 2012.

Location optimisation for antennas by asynchronous particle swarm optimisation

“…Using ray-tracing [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] approaches to predict channel characteristic is effective and fast, and the approaches are also usually applied to multiple input multiple output (MIMO) channel modelling in recent years [25][26][27][28]. Thus, a ray-tracing technique is developed to calculate the channel matrix of MIMO system in this paper.…”

“…where c 1 and c 2 are the learning coefficients used to control the impact of the local and global components in velocity (10). v k+1 j and x k+1 j are the velocity and position of the jth particle at generation k + 1.…”

“…By (10) and (12), particles fly around in the multidimensional solution space and adjust their positions according to their own experience and the experience of neighbouring particles, by exploiting the knowledge of best positions encountered by themselves and their neighbours [38]. The key distinction between an PSO and the APSO is on the updating mechanism, damping boundary condition and mutation scheme.…”

Compact differential dual‐band bandpass filter using single quad‐mode metal‐loaded dielectric resonator

“…Differential topology is widely applied in constructing microwave circuits and systems because of its high immunity to noise and crosstalk. Corresponding to this trend, many devices have been designed in differential configuration, such as power dividers, 1,2 phase shifters, 3,4 antennas, [5][6][7] and filters. [8][9][10][11][12][13] In earlier works, the differential bandpass filters (BPFs) have been extensively developed by using various technologies, such as the printed circuit board, [8][9][10][11] the low temperature co-fired ceramic, 12 and the substrate integrated waveguide.…”

Comparison of GA and DDE for optimizing coverage in indoor environment

“…Because of the often complex indoor propagation environments, intensive measurements are commonly used to collect data and build empirical propagation models that could be used to determine the number and locations of transmitting antennas and establish adequate coverage in regions of interest. In , the model proposes a two‐dimensional ray‐tracing prediction technique associated with a real‐coded mono‐objective genetic algorithm (GA). The GA provides results for antenna position optimization that maximizes the lower field values.…”