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This paper presents a novel design of single-fed, dual-polarized, dual-band slotted antenna with right hand circular polarization (RHCP) at GPS L5 and left-hand circular polarization (LHCP) at SDARS bands which is suitable for hand held device in automotive applications. Dual-band and dual polarization are achieved by introducing four different structured slots in the radiator. The complete dimension of the antenna which is designed and fabricated is only 65 × 65 × 1.6 mm 3. Performance of the fabricated antenna is validated experimentally. Antenna exhibits two independent polarizations and works effectively at 1.17645 GHz for Global Positioning System (GPS L5) and 2.3325 GHz for satellite digital audio radio service (SDARS) bands.

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Although brushless direct current motor (BLDCM) drives are becoming more popular in industrial and commercial applications, there are still significant difficulties and unresolved research issues that must be addressed. In BLDCM drives, commutation current ripple (CCR) and diode freewheeling during non-commutation zone (NCZ) are the major challenges. To overcome these limitations, this paper proposes a novel PWM-Model Antiseptic Control (PWM-MAC) technique to alleviate the freewheeling of the diode. The proposed PWM technique is used to alleviate the diode freewheeling in the NCZ, whereas the DCLV circuit is utilized to obtain variable DC-link voltage to address the CCR in the CZ. The MATLAB/Simulink results are included along with experimental results obtained from a laboratory prototype of 325 W. The proposed module reduces the current ripple by 31.7% and corresponding torque ripples are suppressed by approximately 32.5%. This evidences the performance of the proposed control technique.