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The thesis subject dealt in this report lies in the LE²P framework on the energy sustainability of wireless sensor network. This work is dedicated to the reception and rectifying part of wireless power transfer to give energy sustainability to nodes in a sensor network. This process is not new and originate from the years 1950. The behavior of this process is since well-known in several waveguide such technology as microstrip. But the need of drill in those waveguide circuit may be inconvenient and lead to discrepancy from one circuit to another. This was the motivational keystone to the work address in this report which uses coplanar waveguide (CPW) over microstrip. The conception of such devices goes through a good conceptual and experimental understanding of the waveguide technology. The approach in this document consists of using coplanar waveguide while minimizing its drawbacks, in order to avoid drilling in the substrate and ease the realization of the rectifying part by limiting the human interaction.; Le sujet de thèse abordé dans ce mémoire s'inscrit dans la thématique du LE²P sur l'autonomie énergétique des réseaux de capteurs. Ce travail est axé sur la partie réception et redressement du transfert de l'énergie sans fil pour l'apport d'énergie à des capteurs nomades. Ce procédé n'est pas nouveau et prend son origine dans les années 1950. Les connaissances dans l'appréhension de ce processus sont nombreuses pour certains guides d'onde tels que le microruban. Mais la nécessité de perçages dans ces structures de guide d'onde peut être contraignante et causer des disparités dans une chaîne de construction. Ceci a motivé les travaux présentés dans ce mémoire qui utilise une technologie de guide d'onde coplanaire (CPW) peu exploitée. Ainsi, la conception d'un tel dispositif passe par la maîtrise d'un point de vue conceptuel et expérimental de cette technologie. La démarche consiste à utiliser ce guide d'onde coplanaire en minimisant les effets négatifs que peut engendrer ce dernier, pour s'abroger du besoin de perçage et faciliter la réalisation des dispositifs de redressement en limitant le nombre d'interactions humaines.

International audience; In this paper, we study the impact of electrical and thermal stress on line loss and characteristic impedance of a CoPlanar Waveguides (CPWs). The de-rating of the line propagation constants and impedance characteristic are analyzed and discussed with respect to the stress level applied to the dielectric. The physical mechanisms leading to dielectric properties variation is explained. © 2015 IEEE.

This letter presents a compact, uniplanar, circularly polarized, coplanar waveguide (CPW) spiral antenna for wideband applications. The antenna is directly fed by a 50-Omega CPW from the outside edge of the spiral, thus a balun for matching is not required. This feed provides the capability to have an entire uniplanar array of spirals. It is found that a thick substrate of high dielectric constant absorbs most of the radiated power and results in a unidirectional radiation pattern, which is desirable in many applications. Therefore, this antenna structure is fabricated on a substrate of high dielectric constant, resulting in miniaturization and capability for integrated system applications. It is experimentally verified that the proposed spiral antenna has stable radiation pattern, and its axial ratio is less than 3 dB over the frequency range of 11.4-17.5 GHz.

For application in radar and communication systems operating in the frequency range around 250 GHz, a power amplifier (PA) millimeter-wave monolithic integrated circuit (MMIC) has been developed. The amplifier makes use of a novel coupler approach allowing for in-phase and equal-magnitude distribution of an incoming signal to four parallel output ports. This is possible due to a subtle use of grounded coplanar waveguide and air-bridge microstrip transmission lines, providing different propagation constants. With a size of quarter-wavelength, the coupler is very compact and is the key to the presented PA topology. The amplifier exploits the virtual open occurring due to the identical signals for transistor biasing and matching. The amplifier topology is applied to develop an amplifier MMIC. When biased for maximum gain, it shows a 17-GHz 3-dB bandwidth around its center frequency at 248 GHz with a maximum gain of 32.8 dB. When biased for maximum output power, it provides an output power of 10 and 8.5 dBm at 250 and 270 GHz, respectively. At 250 GHz, it demonstrates a state-of-the-art power density of 125 mW/mm. Due to the amplifier topology, the MMIC is very compact 1.25 x 0.75 mm(2).

This paper presents a quasi-TM approach for the fundamental mode of transmission lines with semiconductor substrates and nonperfect metallic conductors. The approach has allowed us to develop a transmission-line model by properly defining frequency-dependent parameters in terms of the quasi-static electric potential and the electric current density along the propagation direction in the line. The previous quasi-TM analysis avoids the involved numerical root finding process typical in full-wave analysis, and overcomes the limitations of the conventional quasi-TEM approach to account for the effects of the longitudinal currents present both in the lossy substrates and in the nonperfect conductors. The transmission-line parameters have been computed by a hybrid technique that combines the method of lines with the method of the moments (MoM). The total CPU effort has been considerably reduced thanks to the possibility of finding closed-form expressions for the reaction integrals appearing in the MoM. Comparisons with previous computed and measured results show the validity of the present model Ministerio de Educación y Ciencia TEC2004-04249-C02-02, TEC2004-03214

In this letter, a host coplanar waveguide (CPW) loaded with modified Split Ring Resonators (SRR) is presented. In recent publications, it has been demonstrated that the capacitive interaction between the host CPW line and the SRRs is the cause of a right-handed band, which degrades the selectivity of the response. Consequently, an open-ended microstrip stub connected to the rings is used to modify this interaction, and thus have an effective control of the rejection above the pass band. Fortunately, these stubs only affect the frequency position of the right-handed band. As a result, it is quite straightforward to obtain Balanced Composite Right/Left-Handed (CLRH) transmission lines with increased transmission bandwidth and improved rejection levels, which are the main drawbacks of traditional SRR loaded CPW lines. Besides, the response of the modified cell shows a pair of transmission zeros at both sides of the passband. Therefore, this new cell is a very interesting choice for designing balanced CLRH lines and very attractive for filter applications.

This paper presents the design and implementation of uniplanar bandpass filters that use end-coupled slotline resonators and a new kind of multimodal immitance inverter. These inverters are based on an asymmetric shunt-short-circuit coplanar waveguide (CPW) transition, and are modeled using a multimodal circuit model, which takes into account both fundamental modes of the CPW (the even and the odd modes). From this model, analytical design expressions for the inverters are obtained. These structures are used as input/output inverters of a new class of compact low-loss arbitrary-order easily reconfigurable uniplanar filters featuring half-wavelength and quarter-wavelength end-coupled resonators. A multimodal model is obtained for these filters, which allows an accurate analysis, design, and prediction of their behavior. By using these multimodal tools, three second- and fourth-order prototypes, and a second-order frequency-tunable prototype, were designed and implemented. The fourth-order filter has an insertion loss of 2.2 dB at 2 GHz with an out-of-band rejection better than 20 dB in an extremelywide frequency band. The frequency-tunable filter features a tuning range from 1 to 1.37 GHz with quasi-constant 3-dB bandwidth from 121 to 135 MHz. The measurements show a good agreement with the proposed multimodal model, thus validating the model and the design methodology.

The largest 21st century radio telescope, the Square Kilometre Array (SKA) is now being planned, and the first phase of construction is estimated to commence in the year 2016. Phased array technology, the key feature of the SKA, requires the use of a tremendous number of receivers, estimated at approximately 37 million. Therefore, in the context of this project, the Low Noise Amplifier (LNA) located at the front end of the receiver chain remains the critical block. The demanding specifications in terms of bandwidth, low power consumption, low cost and low noise characteristics make the LNA topologies and their design methodologies one of the most challenging tasks for the realisation of the SKA. The LNA design is a compromise between the topology selection, wideband matching for a low noise figure, low power consumption and linearity. Considering these critical issues, this thesis describes the procedure for designing a monolithic microwave integrated circuit (MMIC) LNA for operation in the mid frequency band (400 MHz to 1.4 GHz) of the SKA. The main focus of this work is to investigate the potential of MMIC LNA designs based on a novel InGaAs/InAlAs/InP pHEMT developed for 1 µm gate length transistors, fabricated at The University of Manchester. An accurate technique for the extraction of empirical linear and nonlinear models for the fabricated active devices has been developed. In addition to the linear and nonlinear model of the transistors, precise models for passive devices have also been obtained and incorporated in the design of the amplifiers. The models show excellent agreement between measured and modelled DC and RF data. These models have been used in designing single, double and differential stage MMIC LNAs. The LNAs were designed for a 50 Ω input and output impedance. The excellent fits between the measured and modelled S-parameters for single and double stage single-ended LNAs reflects the accurate models that have been developed. The single stage LNA achieved a gain ranging from 9 to 13 dB over the band of operation. The gain was increased between 27 dB and 36 dB for the double stage and differential LNA designs. The measured noise figures obtained were higher by ~0.3 to ~0.8 dB when compared to the simulated figures. This is due to several factors which are discussed in this thesis. The single stage design consumes only a third of the power (47 mW) of that required for the double stage design, when driven from a 3 V supply. All designs were unconditionally stable. The chip sizes of the fabricated MMIC LNAs were 1.5 x 1.5 mm2 and 1.6 x 2.5 mm2 for the single and double stage designs respectively. Significantly, a series of differential input to single-ended output LNAs became of interest for use in the Square Kilometre Array (SKA), as it utilises differential output antennas in some of its configurations. The single-ended output is preferable for interfacing to the subsequent stages in the analogue chain. A noise figure of less than 0.9 dB with a power consumption of 180 mW is expected for these designs.

In this paper, a simple geometrical modification of the well-known split-ring resonator (SRR) topology is proposed. This modification consists of joining the opposite sides of the rings by means of an inductive connection. Due to this modification, it is possible to synthesize a dual composite right-/left-handed artificial transmission line from a host coplanar waveguide (CPW). In addition, it is quite straightforward to synthesize a dual balanced line showing a wider transmission bandwidth (around 13% for 3 GHz and 8% for 6 GHz) with this new SRR geometry. In fact, in order to design a balanced line, one must just modify the inductance of the direct connection between the rings, which can be derived from the equivalent circuit of this new ring, which is also presented in this paper. The final result is a balanced artificial CPW transmission line with a dual composite right-/left-handed behavior. In this case, the right-handed transmission band is placed below the left-handed one, and there is no frequency separation between both transmission bands. © 1963-2012 IEEE., This work was supported in part by the Ministerio de Ciencia e Innovacion, Spanish Goverment, under Research Projects TEC2010-21520-C04-03 and TEC2010-21520-C04-01 and by the Autonomous Government of Castilla-La Mancha under Research Projects PPII10-0047-0220 and PPII10-0027-1277.

This paper presents a novel electrochemically assisted wet-etching method for maskless selective removal of metal layers. This method has been developed as the key process step for enabling the fabrication of low-loss 3-D micromachined silicon-on-insulator-based radio-frequency microelectromechanical systems transmission line components, consisting of a silicon core in the device layer covered by a gold metallization layer. For this application, the full-wafer sputtered metallization layer must be locally removed on the handle layer to guarantee for a well-defined and low-loss coplanar-waveguide propagation mode in the slots of the transmission line. It is not possible to use conventional photolithography or shadow masking. Gold areas to be etched are biased by a 1.2-V potential difference to a saturated calomel reference electrode in a NaCl(aq) solution. The measured etch rate of the proposed local electrochemically biased etching process is 520 nm/min, and no detectable etching was observed on unbiased areas even after a 1-h etch. The suitability of different adhesion layers has been investigated, and Ti-based adhesion layers were found to result in the highest yield. The new etching method has been successfully applied for the fabrication of transmission lines with integrated microswitches, lowering the insertion loss of the waveguide at 10 GHz from 1.3 to 0.3 dB/mm. The issue of unwanted thin metallic connections caused by secondary deposition during sputtering is discussed but found not to significantly affect the process yield. Finally, local removal of gold on isolated features even within the device layer is presented for locally removing the metallization on stoppers of laterally moving electrostatic actuators, to drastically reduce the mechanical wear on stopper tips. © 2011 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.QC 20111207

parylene-N is used as a dielectric layer to create ultra low-loss 3-D vertical interconnects and coplanar waveguide (CPW) transmission lines on a CMOS substrate. Insertion loss of 0.013 dB for a 3-D vertical interconnect through a 15- m-thick parylene-N layer and 0.56 dB/mm for a 50- CPW line on the parylene-N layer (compared to 1.85 dB/mm on a standard CMOS substrate) are measured at 40 GHz. L-shaped, U-shaped, and T-junction CPW structures are also fabricated with underpasses that eliminate the discontinuities arisen from the slot-line mode and are characterized up to 40 GHz. A 3-D low-noise amplifier using these post-processed structures on a 0.13- m CMOS technology is also presented along with the investigation of parasitic effects for accurate simulation of such a 3-D circuit. The 3-D circuit implementation reduces the attenuation per unit length of the transmission lines, while preserving the CMOS chip area (in this specific design) by approximately 25%. The 3-D amplifier measures a gain of 13 dB at 2 GHz with 3-dB bandwidth of 500 MHz, noise figure of 3.3 dB, and output 1-dB compression point of + 4.6 dBm. Room-temperature processing, simple fabrication, low-loss performance, and compatibility with the CMOS process make this technology a suitable choice for future 3-D CMOS and BiCMOS monolithic microwave integrated circuit applications that currently suffer from high substrate loss and crosstalk.

A mask programmable technology to implement RF and microwave integrated circuits using an array of standard 90-nm CMOS transistors is presented. Using this technology, three wideband amplifiers with more than 15-dB forward transmission gain operating in different frequency bands inside a 4-22-GHz range are implemented. The amplifiers achieve high gain-bandwidth products (79-96 GHz) despite their standard multistage designs. These amplifiers are based on an identical transistor array interconnected with application specific coplanar waveguide (CPW) transmission lines and on-chip capacitors and resistors. CPW lines are implemented using a one-metal-layer post-processing technology over a thick Parylene-N (15 mu m) dielectric layer that enables very low loss lines (similar to 0.6 dB/mm at 20 GHz) and high-performance CMOS amplifiers. The proposed integration approach has the potential for implementing cost-efficient and high-performance RF and microwave circuits with a short turnaround time.

International audience; This paper presents the performance of a wideband 0.13μm BiCMOS SiGe power amplifier (PA) for millimeter wave (mmW) applications. The design and the measured results of a monolithic integrated low-voltage PA are reported. A balanced four-stage common emitter circuit topology was used to achieve greater than 17dB of power gain from 59 GHz to 71GHz. As a result, the amplifier delivers 18dBm of maximum RF output power and 14.5dBm output power at 1dB compression. The circuit shows 7.8% of power added efficiency (PAE) from a 1.8V supply voltage at 65 GHz. The power amplifier was fully integrated including matching elements and bias circuit. The matching networks use coplanar waveguide (CPW) lines and MIM capacitors for high integration purpose.

Within the past few years, the field of Electron Spin Resonance has become an important tool in physical, chemical and biological research. However, in many cases its usefulness is limited by the sensitivity of the experimental setup. A typical example is the study of very limited sample quantities such as tissues, cellular structures, single cells, and also thin films in microelectronic technologies. For such volume limited samples, the typical dimensions and/or spatial variations of the properties of interest range between 1 µm and 1 mm. Present X-band ESR spectrometers are optimized for samples having a volume between (1 mm)3 and (1 cm)3, and achieve a spin sensitivity of about 1010 spins/G√Hz at room temperature. Setting up new high sensitivity ESR spectrometers would overcome this limitation and open the way to numerous new applications. The goal of the present work is to study and develop innovative devices in combination with modern continuous ESR detection method to achieve a spin sensitivity of 109 spins/G√Hz or better at room temperature, specifically conceived for samples having dimensions and/or spatial variations in the range between 1 µm and 1 mm. We mainly focus our investigation efforts on the design of ESR-setups based on miniaturized sensitive devices. Miniaturization concerns size reduction of the sensitive volume where the sample will be placed, i.e., the region in which the microwave magnetic field is generated. In this work two approaches will be investigated. Inductive transverse magnetization detection by means of planar structures based on coplanar waveguide (CPW) resonator design. Single turn coils and straight trace constrictions with different dimensions are designed as sensitive regions to accommodate the appropriate sample size. These constrictions are built with open-ended half-wavelength and shorted (or shunted) quarter-wavelength lines related to the working resonance frequency. Appropriate microfabrication technologies are also developed based on two substrate candidates, SU-8 and RO4003C, with Aluminum and Copper metals, respectively. Performance of the RO4003C based-resonators proves to be better than that for the SU-8 based ones in terms of the conversion factor describing the efficiency of conversion of microwave power to magnetic field strength. The analysis we have performed shows that the dielectric losses induced in the RO4003C substrate are much lower than those induced in SU-8 one. This improves the Q-factor by almost a factor 10. Since the conversion factor varies as Q1/2, this, in turn, enhances the power conversion efficiency by almost a factor 3. Detection efficiency is also improved by almost the same factor. As a result, a spin sensitivity of about 109 spins/G√Hz is achieved at room temperature for sensitive volumes of about (100 µm)3. This result is one order of magnitude better than that of existing X-band spectrometers. Longitudinal magnetization detection using a Hall-based probe. A resonant cavity and a CPW-resonator are used to generate the microwave field. Rather than a large rectangular cavity and its disperse field lines, the CPW-resonator offers a smaller structure. Its compact geometry is suitable for small volumes, since it concentrates the microwave magnetic field precisely at the sample. This approach eliminates several experimental difficulties of cavity-employed ESR spectroscopy and better controls the electromagnetic environment of the sample, avoiding the properties of the cavity resonator which suffer from thermal drifts and background instabilities. In addition, thanks to their greater sensitivity, the CPW-resonators require much less microwave power than waveguide cavities, to generate the same microwave magnetic field. The achieved spin sensitivity is about 109 spins/G√Hz at room temperature for sensitive volumes of about (10 µm)3 . This result is, once more, one order of magnitude better than that of conventional X-band spectrometers. The obtained results confirm the effectiveness of the combination of the CPW-resonators for small sample analysis for practical enhancement of the ESR spectrometer sensitivity at X-band frequencies. Furthermore, a key aspect of the present work is the ability to go further in miniaturization: the concept of coplanar waveguide structures is very simple and easy to implement for the required ESR measurements without too much additional design complexity and change to fabrication procedures. This should be very promising, and especially highly motivating to achieve in-vivo ESR measurements inside living organism and to perform high spatial resolution ESR-imaging.

Monopole antennas have been widely used in the telecommunication industry in recent years. Most of the monopole antennas are designed to operate at Wireless Local Area Network (WLAN) application which has the advantage of unlicensed Industrial, Scientific, Medical (ISM) bands. ISM bands include of IEEE 802.11 a/b/g WLAN standards which have different speed data rates and operating frequency. The current issue stated that people always complain about their WiFi's signal coverage which is normally low. In an effort to solve this coverage problem, improvement must be made on the antenna's gain. A conventional gain of a monopole antenna operated at 2.4 GHz is normally 2 dBi. A coplanar waveguide (CPW) fed WLAN monopole antenna which is operated at 2.4 GHz with gain improvement is designed. In this project, the gain is improved by using the parasitic element technique. The concept is based on the Yagi-Uda antenna which consists of reflector and directors. The simulated and measured gain achieved is 6.9 dBi and 7.9 dBi respectively. Hence, the gain increment is 5.9 dBi if compared to the conventional gain. The designed antenna produced a directional radiation pattern which covers almost 90° of the antenna's coverage area.

The design and performance analysis of a coplanar waveguide fed printed monopole antenna for dual polarization is presented. The rectangular patch monopole has an hour glass shaped slot engraved on it whereas the two ground planes of the CPW are loaded with spiral shaped slots. The feed is made asymmetric with respect to the patch for enhancing the horizontal gain component. The measured (S11

In this paper, a uniplanar RF-MEMS secondorder bandpass filter with reconfigurable centre frequency is presented. It is based on quarter-wavelength slotline resonators and CPW-slotline multimodal immittance inverters (MIIs), which are reconfigured using RF-MEMS switchable CPW airbridges (SABs). The filter can be adequately explained and designed using multimodal theory and circuit models. A surface micromachining process on high-resistivity silicon substrate was used to fabricate the filter. Experimental results show frequency reconfigurability from 12 GHz to 13 GHz, maintaining the same relative bandwidth, and insertion losses of 4.6 dB and 4.7 dB respectively.