|ชื่อเรื่อง||:||Autonomous smart antenna systems for future mobile devices|
|คำค้น||:||smart antenna systems , feeding network|
|หน่วยงาน||:||Edinburgh Research Archive, United Kingdom|
|ผู้ร่วมงาน||:||Arslan, Tughrul , Benkrid, Khaled|
|ความสัมพันธ์||:||Wei Zhou; Noordin, Nurul; Haridas, Nakul; El-Rayis, Ahmed; Erdogan, Ahmet; Arslan, Tughrul, "A WiFi/4G compact feeding network for an 8-element circular antenna array," 2011 Loughborough Antennas and Propagation Conference (LAPC),vol., no., pp.1,4, 14-15 Nov. 2011 , Yan Chiew Wong; Wei Zhou; El-Rayis, Ahmed; Haridas, Nakul; Erdogan, Ahmet; Arslan, Tughrul, "Practical design strategy for two-phase step up DC-DC Fibonacci Switched- Capacitor converter," 2011 20th European Conference on Circuit Theory and Design (ECCTD), vol., no., pp.817,820, 29-31 Aug. 2011 , Noordin, Nurul; Wei Zhou; El-Rayis, Ahmed; Haridas, Nakul; Erdogan, Ahmet; Arslan, Tughrul, "Single-feed polarization reconfigurable patch antenna," 2012 IEEE Antennas and Propagation Society International Symposium (APSURSI), vol., no., pp.1,2, 8-14 July 2012 , Wei Zhou; Haridas, Nakul; El-Rayis, Ahmed; Erdogan, Ahmet; Benkrid, Khaled; Arslan, Tughrul, "Enhanced Wilkinson divider on Si substrate for energy efficient microwave applications," 2012 Loughborough Antennas and Propagation Conference (LAPC), vol., no., pp.1,4, 12-13 Nov. 2012 , Wei Zhou; Arslan, Tughrul; Benkrid, Khaled; El-Rayis, Ahmed; Haridas, Nakul, "Reconfigurable feeding network for GSM/GPS/3G/WiFi and global LTE applications," 2013 IEEE International Symposium on Circuits and Systems (ISCAS), vol., no., pp.958,961, 19- 23 May 2013 , Wei, Zhou; Arslan, Tughrul; Flynn, Brian, "A reconfigurable feed network for a dual circularly polarised antenna array," 2013 IEEE 24th International Symposium on Personal Indoor and Mobile Radio Communications (PIMRC), vol., no., pp.430,434, 8-11 Sept. 2013 , Wei, Zhou; Arslan, Tughrul, "A bidirectional planar monopole antenna array for WiFi/Bluetooth and LTE mobile applications," 2013 Loughborough Antennas and Propagation Conference (LAPC), vol., no., pp.190,193, 11-12 Nov. 2013 , Wei, Zhou; Arslan, Tughrul, "Planar monopole antenna with Archimedean spiral slot for WiFi/Bluetooth and LTE applications," 2013 Loughborough Antennas and Propagation Conference (LAPC), vol., no., pp.186, 189, 11-12 Nov. 2013|
Along with the current trend of wireless technology innovation, wideband, compact size, low-profile, lightweight and multiple functional antenna and array designs are becoming more attractive in many applications. Conventional wireless systems utilise omni-directional or sectored antenna systems. The disadvantage of such antenna systems is that the electromagnetic energy, required by a particular user located in a certain direction, is radiated unnecessarily in every direction within the entire cell, hence causing interference to other users in the system. In order to limit this source of interference and direct the energy to the desired user, smart antenna systems have been investigated and developed. This thesis presents the design, simulation, fabrication and full implementation of a novel smart antenna system for future mobile applications. The design and characterisation of a novel antenna structure and four-element liner array geometry for smart antenna systems are proposed in the first stage of this study. Firstly, a miniaturised microstrip-fed planar monopole antenna with Archimedean spiral slots to cover WiFi/Bluetooth and LTE mobile applications has been demonstrated. The fundamental structure of the proposed antenna element is a circular patch, which operates in high frequency range, for the purpose of miniaturising the circuit dimension. In order to achieve a multi-band performance, Archimedean spiral slots, acting as resonance paths, have been etched on the circular patch antenna. Different shapes of Archimedean spiral slots have been investigated and compared. The miniaturised and optimised antenna achieves a bandwidth of 2.2GHz to 2.9GHz covering WiFi/Bluetooth (2.45GHz) and LTE (2.6GHz) mobile standards. Then a four-element linear antenna array geometry utilising the planar monopole elements with Archimedean spiral slots has been described. All the relevant parameters have been studied and evaluated. Different phase shifts are excited for the array elements, and the main beam scanning range has been simulated and analysed. The second stage of the study presents several feeding network structures, which control the amplitude and phase excitations of the smart antenna elements. Research begins with the basic Wilkinson power divider configuration. Then this thesis presents a compact feeding network for circular antenna array, reconfigurable feeding networks for tuning the operating frequency and polarisations, a feeding network on high resistivity silicon (HRS), and an ultrawide-band (UWB) feeding network covering from 0.5GHz to 10GHz. The UWB feeding network is used to establish the smart antenna array system. Different topologies of phase shifters are discussed in the third stage, including ferrite phase shifters and planar phase shifters using switched delay line and loaded transmission line technologies. Diodes, FETs, MMIC and MEMS are integrated into different configurations. Based on the comparison, a low loss and high accurate Hittite MMIC analogue phase shifter has been selected and fully evaluated for this implementation. For the purpose of impedance matching and field matching, compact and ultra wideband CPW-to-Microstrip transitions are utilised between the phase shifters, feeding network and antenna elements. Finally, the fully integrated smart antenna array achieves a 10dB reflection coefficient from 2.25GHz to 2.8GHz, which covers WiFi/Bluetooth (2.45GHz) and LTE (2.6GHz) mobile applications. By appropriately controlling the voltage on the phase shifters, the main beam of the antenna array is steered ±50° and ±52°, for 2.45GHz and 2.6GHz, respectively. Furthermore, the smart antenna array demonstrates a gain of 8.5dBi with 40° 3dB bandwidth in broadside direction, and has more than 10dB side lobe level suppression across the scan. The final stage of the study investigates hardware and software automatic control systems for the smart antenna array. Two microcontrollers PIC18F4550 and LPC1768 are utilised to build the control PCBs. Using the graphical user interfaces provided in this thesis, it is able to configure the beam steering of the smart antenna array, which allows the user to analyse and optimise the signal strength of the received WiFi signals around the mobile device. The design strategies proposed in this thesis contribute to the realisation of adaptable and autonomous smart phone systems.
Zhou, Wei . (2558). Autonomous smart antenna systems for future mobile devices.
กรุงเทพมหานคร : Edinburgh Research Archive, United Kingdom .
Zhou, Wei . 2558. "Autonomous smart antenna systems for future mobile devices".
กรุงเทพมหานคร : Edinburgh Research Archive, United Kingdom .
Zhou, Wei . "Autonomous smart antenna systems for future mobile devices."
กรุงเทพมหานคร : Edinburgh Research Archive, United Kingdom , 2558. Print.
Zhou, Wei . Autonomous smart antenna systems for future mobile devices. กรุงเทพมหานคร : Edinburgh Research Archive, United Kingdom ; 2558.