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A dual-layered six-port front-end circuit on the basis of substrate-integrated waveguide (SIW) technology is presented and demonstrated. The use of SIW technology allows the development of a compact circuit with low radiation loss at millimetrewave frequencies. The six-port architecture makes use of multilayer couplers that provide a wide coupling area through two slots; a new broadband SIW phase shifter composed of two H-plane stub lines and a reference line; and two SIW power dividers. The six-port design is free from loads as in the case of classic modified six-port architectures with eight ports. To validate the proposed concept, an integrated broadband six-port front-end circuit prototype was designed, fabricated and measured. Simulation and measurement results show that the proposed six-port circuit can easily operate at 60 GHz for V-band system applications. The two-layered structure presents interesting technological features including low profile, small volume and footprint and highdensity integration. [ABSTRACT FROM AUTHOR]

A Butler beam-forming network with low sidelobe level (SLL) is proposed and demonstrated on the basis of variable couplers. A set of couplers with 0.75, 1.26, 3, 6 and 8 dB coupling levels are required to achieve an SLL of -13.6, -20 and -30 dB. Such variable coupling is achieved by creating a movable mirror structure in the common region of perpendicularly or cross-coupled waveguide building blocks. This mirror is composed of a 5×7 cylindrical rod array. The coupling and directivity characteristics depend on the position of this proposed fringe structure. In this work, WR28 is used to demonstrate the capability of this type of coupler over 26-30 GHz bandwidth. Structure usefulness and design procedure are validated by electromagnetic simulation high frequency structural simulator (HFSS) and prototype experimentation. Very good results are observed, that have also demonstrated attractive performances of the coupler. Measured results of couplers are used to assess the properties of Butler matrix with excitation coefficients corresponding to -13.6, -20 and -30 dB of SLLs. Radiation patterns obtained by this investigation show a promising performance. This proposed technique allows flexibility in the choice of excitation coefficients without degradation on the efficiency. [ABSTRACT FROM AUTHOR]

In this study, a neutral-current suppressor is proposed. The proposed neutral-current suppressor comprises a zero-sequence transformer, a single-phase power converter and a rectifier. The proposed zero-sequence transformer is implemented by only two single-phase transformers, which are connected to three-phase lines of the three-phase four-wire distribution power system to supply a zero-sequence current path. The single-phase power converter is connected between the zero-sequence transformer and neutral line. A rectifier with small power rating is connected to the DC bus of single-phase power converter for overcoming the power loss of single-phase power converter to sustain a constant DC voltage. The performance of neutral-current suppression for the zero-sequence transformer is advanced by controlling the single-phase power converter so as to make the neutral load current flow through the proposed neutral-current suppressor. Moreover, the proposed neutral-current suppressor can also avoid the neutral current caused by the unbalanced voltage of three-phase four-wire distribution power systems. Hence, the proposed neutral-current suppressor is an effective solution to the neutral-current problem of three-phase four-wire distribution power systems. Both computer simulation and experimental results verify that the proposed neutral-current suppressor can achieve the expected performance. [ABSTRACT FROM AUTHOR]

A new balanced oscillator is proposed to generate anti-phase sources at Ku band. The proposed oscillator is stabilised with the TE210 differential mode of a single planar substrate integrated waveguide (SIW) rectangular cavity with mutually locked dual anti-phase outputs. The unloaded-Q of this resonator extracted through mixed mode S-parameters is 370 at 14 GHz. The differential coupling mechanism is presented and the coupling coefficient is parametrically studied. The proposed balanced oscillator provides 6.9 and 7.2 dBm output power for each balanced output with a phase noise of -101 dBc/Hz at 100 kHz offset measured at 14 GHz. The amplitude and phase balances of the two output signals are verified with measurement. The combined differential output power is 10.8 dBm and the phase noise is -109 dBc/Hz at 100 kHz offset. [ABSTRACT FROM AUTHOR]

In this study, a three-leg power converter battery charger for the lithium-iron phosphate battery is proposed. The proposed power converter is configured by a three-leg power converter. The operating principle of the proposed three-leg power converter is based on the concept of the common mode and differential mode used in the analysis of the conducted electromagnetic interference. In the proposed battery charger, no transformer is required for matching the voltage levels between the utility with a higher AC voltage and the battery set with a lower DC voltage. Moreover, the unity input power factor can be obtained. A prototype is developed and tested to verify the performance of the proposed battery charger. The experimental results show the performance of the proposed power converter is as expected. [ABSTRACT FROM AUTHOR]

Substrate-integrated waveguide (SIW) technology represents an emerging and very promising candidate for the development of circuits and components operating in the microwave and millimetre-wave region. SIW structures are generally fabricated by using two rows of conducting cylinders or slots embedded in a dielectric substrate that connects two parallel metal plates, and permit the implementation of classical rectangular waveguide components in planar form, along with printed circuitry, active devices and antennas. This study aims to provide an overview of the recent advances in the modelling, design and technological implementation of SIW structures and components. [ABSTRACT FROM AUTHOR]

Sensor networks have the potential to revolutionise the capture, processing and communication of critical data for use of disaster rescue and relief. In order to provide a dependable rescue capability through dynamically integrating newly developed and legacy sensor systems with other systems and computing, new methodologies are required for the dependable integration of services in heterogeneous environments. In this study, the authors present a new architectural model which can proactively self-adapt to changes and evolution occurring in the provision of search and rescue capabilities in a dynamic environment. This performance and reliability of the approach has been evaluated using simulations in a dynamic environment and demonstrated through developing and testing a demonstration system for a scenario of disaster area monitoring. [ABSTRACT FROM AUTHOR]

A novel class of substrate-integrated waveguides (SIWs) is presented, based on the concept of the classical ridge rectangular waveguide, which permits the design of broadband, compact and low-loss integrated components and interconnects. Two configurations are proposed. The former is the ridge SIW, where the structure is integrated in a dielectric substrate with top and bottom metal layers, and comprises two-sided rows of full-height metal cylinders and a central row of partial-height metal posts connected at their bottom by a metal strip. The latter is the ridge substrate-integrated slab waveguide; this structure presents a geometry similar to the ridge SIW, but includes additional air holes to further enhance the bandwidth. The design and experimental verification of two prototypes, covering the frequency band from 6.8 to 25 GHz and from 7.1 to 30.7 GHz, respectively, are also presented. The proposed structures exhibit a mono-modal bandwidth three times broader than classical rectangular waveguides or SIWs, and their size is half of the SIW with the same cut-off frequency. [ABSTRACT FROM AUTHOR]

This study presents a novel approach for designing broadband single layer printed log-periodic dipole array (PLPDA) antenna fed by substrate integrated waveguide (SIW). The PLPDA antenna has the merits of wide bandwidth, low profile and light weight, which should be fed by the balanced line. The balanced line, created by the geometric features of the SIW, provides a balun with a considerably wide bandwidth with low profile, broad dominant mode bandwidth, low insertion loss and so on. Prototype of the proposed substrate integrated printed log-periodic dipole array (SIPLPDA) antenna and 1×4 antenna array at Ka band are designed and fabricated; the measured data are in good agreement with the simulated results. [ABSTRACT FROM AUTHOR]

In this study, a new type of substrate integrated waveguide (SIW) beamforming network (BFN) based on the principle of the modified R-KR lens has been proposed and experimentally verified. Through the detailed analysis of such a structure, a prototype lens with 15 input ports is implemented together with an SIW slot array antenna at 30 GHz, which is able to cover a wide angle of (-59°, 59°) with its 3 dB beam-width. The measured radiation efficiencies of the lens excited at different ports range from 21.6 to 40.8%. This type of BFN takes the advantages of low profile, low cost and high performance, and may be applied to millimetre-wave mobile communications and radars with beam switching technology. [ABSTRACT FROM AUTHOR]

A Ka-band sub-harmonically pumped up-converter antenna employing the substrate integrated waveguide (SIW) technique is proposed and used to realise a low-cost transmitter together with spatial power combining architecture in this paper. A single Ka-band sub-harmonically pumped up-converter using SIW band-pass filter is developed, exhibiting a conversion loss of about 7 dB. Based on the designed up-converter and SIW feeding antipodal linearly tapered slot antenna (SIW-ALTSA), the integrated up-converter antenna is designed and fabricated. Measured results of equivalent isotropic radiated power (EIRP) and radiation patterns are given. Finally, a 2×2 up-converter antenna array is designed and fabricated. Measured result shows the array has a power combining efficiency of above 90% and IM3 EIRP of 16 dBm. In close-range point-to-point communication and radar systems, the demonstrated millimetre-wave sub-harmonically pumped up-converter antenna array can be considered as a transmitter because of its low cost, high dynamic range and high linearity. [ABSTRACT FROM AUTHOR]

Wave radios in the past have used passive wide-band with no multiple access (MA) coded interferometer architectures in modulator and demodulator circuits for QPSK digital data transmission and reception. The authors provide information and design insight on the use of MA coded interferometers in modulator and demodulator for UWB wave radio. Wave radio fitted with hardware MA coded interferometers offers MA to users as does CDMA using data codes. Experimental and simulation analyses of coded interferometers show that it is possible to establish a one-to-one wave radio hardware link by means of hardware-based codes (addresses). The number of UWB hardware-coded interferometers investigated is limited to three codes (code 0, code 1 and code 2) for demonstration purposes only. [ABSTRACT FROM AUTHOR]

Low sidelobe longitudinal slot array antennas are investigated based on substrate integrated waveguide (SIW) technology. The design method consists of the characterisation of the radiating element, the synthesis of the linear array and the development of the planar array including a feeding power divider by performing full-wave electromagnetic simulations for the final accurate design. Two planar slot array antennas are fabricated with a normal printed circuit board (PCB) process. Low sidelobe features are verified by the measured results which are in agreement with the simulated results. For an 8×8 SIW slot array antenna, the measured sidelobe levels (SLLs) are below -36 dB in the H-plane and below -25 dB in the E-plane with the Gain of 20.3 dB at 9.9 GHz. And for a 16×16 antenna, the SLLs are below -30 dB both in the E-plane and H-plane with the Gain of 24.4 dB at 10 GHz. The achieved design goals on the radiation patterns therefore validate the proposed low sidelobe SIW slot array antennas to be valuable candidates for high performance communication and radar applications. [ABSTRACT FROM AUTHOR]

A tunable dual-band bandpass microstrip filter is proposed and presented. It is composed of two pairs of quarter-wavelength transmission line resonators and two bandstop structures made of open stubs. Each operation bandpass frequency, denoted by f1 and f2, is generated by a pair of coupled resonators. The first coupled resonator is fed via a tap-coupled structure, while the second is fed through a coupling structure. The tunability of each bandpass and harmonic suppression is achieved by modifying the electrical length of the resonators and the electrical length of the open stubs by using varactor-diode capacitors. Finally, a 2.5 and 4.25 GHz dual band bandpass filter is designed, fabricated and measured as one example and a tunability of 22.2% and 19.6%, respectively, is obtained for the first and second bands. These excellent experimental results validate the proposed structure and design technique for dual-band bandpass filters. [ABSTRACT FROM AUTHOR]

A new model based on the numerical electric field analysis has been developed to predict the flashover voltage of ice-covered HV insulators, under AC voltage. By analysing the electric field and combining the U–I and re-ignition characteristics of the arc, the arc propagation process and the flashover voltage of the ice-covered insulators under AC voltage can be obtained. Moreover, the peak value of the voltage on the residual ice is calculated based on the electric field model, which can avoid the errors caused by the simplified residual ice resistance calculation methods in the mathematical model. The results obtained from the electric field flashover model have been compared with other mathematical and experimental results and got a great agreement. [ABSTRACT FROM AUTHOR]

A new class of substrate-integrated waveguides (SIWs) is proposed, which highlights a novel synthesis of waveguide circuits using metallic via-slot arrays instead of via-hole arrays. When the gaps between the slots are small enough, the broadside dimension of equivalent rectangular waveguide is approximately equal to the spacing between the inner walls of slots. Therefore the size of the SIW can directly be used to calculate propagation constants almost without phase bias. This new design is of critical importance in the design of substrate-integrated circuits (SICs) with fine and sensitive geometrical details with respect to circuit response such as filters and resonators. In this way, the design of SICs based on the new SIW structures can greatly be simplified. A finite difference frequency-domain method accelerated by an implicitly restarted Arnoldi method is developed to model the substrate-integrated resonant cavities with leakage. Simulated and measured results have confirmed the fact that conventional waveguide components are very similar to the SIW counterparts of the same structure. [ABSTRACT FROM AUTHOR]

A novel power converter topology for three-phase four-wire hybrid power filter is proposed. It is configured by a three-arm bridge structure without split capacitors. The salient feature of the three-phase four-wire hybrid power filter using the proposed power converter is that it permits the neutral line of the utility directly connecting to the negative or positive terminal of the DC capacitor located in the DC side of the power converter. Consequently, the power converter uses less number of power electronic switches to reduce the manufacturing cost. A three-phase four-wire hybrid power filter prototype is developed and tested to demonstrate the performance of the three-phase four-wire hybrid power filter using the proposed power converter. Experimental results show that the proposed three-phase four-wire hybrid power filter using the proposed power converter has the expected performance. [ABSTRACT FROM AUTHOR]

A compact planar E-plane monopulse antenna is proposed and realised at 36.5 GHz for millimetre-wave radar or direction-finding system application, which is built on the substrate integrated waveguide (SIW) technology. A phase shifter having a non-uniform SIW width configuration is self-consistently made of a periodically embedded via array and it can achieve good performances over a relative broad bandwidth. A 180° directional coupler incorporating this proposed phase shifter structure is developed in the design of an integrated feeding network for the monopulse antenna. Four elements array based on the configuration of antipodal linearly tapered slot antenna is designed as radiator, offering a pair of ‘sum’ and ‘difference’ beams along the long direction of the substrate. Measured gain of the ‘sum’ beam is higher than 16 dBi, whereas the zero depth of the ‘difference’ beam is lower than –38 dB. This type of monopulse antenna presents an excellent candidate in the development of intelligent millimetre-wave directional-finding system. [ABSTRACT FROM AUTHOR]

This paper proposes a dualband frequency-selective surface (FSS) based on substrate-integrated waveguide (SIW) technology. This novel dualband FSS is constructed using double square loop slots (DSLSs) and an SIW cavity. Its frequency performance is investigated by numerical simulation using the finite difference frequency domain (FDFD) method. Another dualband FSS, constructed using convoluted double square loop slots (CDSLSs) and an SIW cavity is also investigated in order to get close passband spacing. Simulation results show that these dualband FSSs have the advantages of higher selectivity and passband insensitivity to the incident angles and polarisations, compared with conventional multiband FSSs. Experiments are carried out to verify the simulated results, and the measured results show a promising performance of the proposed FSS. [ABSTRACT FROM AUTHOR]

The parallel operation of several low-capacity inverters is better than a singular high-capacity inverter owing to the advantages of better extensibility and reliability. A simplified control method for parallel-connected inverters is proposed, which can balance the current distribution among the parallel-connected inverters with no interconnected communication lines. To verify the performance of the proposed control method, a prototype consisting of two inverters has been developed. The experimental results verify that the performance of the proposed control method is as desired. [ABSTRACT FROM AUTHOR]

Novel single-layer planar directional couplers based on substrate integrated waveguide (SIW) technology are presented. These proposed couplers are totally realised in single-layer dielectric substrate with metallicvias, and fabricated using a standard PCB process. Prototypes of -3 dB, -6 dB and -10 dB SIW directional couplers are designed, fabricated and measured. It is concluded from the simulated and measured results that these couplers show good performances with broad operation bandwidth, low insertion loss, low return loss and high isolation etc. The characteristics of compact size and planar form make such SIW directional couplers can be easily integrated in microwave and millimetre-wave planar circuits. [ABSTRACT FROM AUTHOR]

A new direction-of-arrival estimation method based on six-port technology is presented. In order to obtain the beam direction, the proposed circuit uses a two-channel multi-band receiver and analogue signal processing of the six-port circuit output signals. A practical approach for estimating the beam direction has also been proposed. This approach, based on the detection of the minimum magnitude of the in-quadrature output signal, avoids the necessity of computing the angle-of-arrival value. A dual-band prototype circuit was designed and fabricated. Simulation results in the S and C frequency bands are presented and discussed. In order to validate this method, measurements were carried out in the C-band. These results show a maximal angle-of-arrival estimation error of about 3%. Therefore, low-cost direction-of-arrival measurements can be performed using this new method. [ABSTRACT FROM AUTHOR]

A novel technique for designing and realising nonradiative dielectric (NRD) waveguide circuits based on the concept of substrate integrated circuits (SICs) is proposed and demonstrated for the first time. In this new scheme, the substrate integrated NRD (SINRD) guide is created or synthesised by drilling a pattern of air holes in a planar dielectric substrate. Furthermore, metallised holes are also introduced to enclose the NRD guide. Using this configuration, an integrated waveguide transition and mode suppressor can be realised. Dispersion analysis and design considerations for the proposed structure are presented and discussed. It is shown that this new approach can be applied over a wide range of microwave and millimetre-wave frequencies for high-density circuit integration and low-cost system applications. Measured results of a number of showcase circuits validate the design method, which include a bandpass filter, a directional coupler and an integrated transition between an SINRD guide and a rectangular waveguide. [ABSTRACT FROM AUTHOR]

A planar microwave diplexer based on the substrate integrated waveguide (SIW) technique is presented in the paper. The SIW-microstrip transition and SIW filter are experimentally investigated, and then a C-band SIW diplexer is designed and fabricated using a standard PCB process. The relative bandwidths of up and down channels are 3% and 4.8% at 5.96 GHz and 5.42 GHz, respectively. The measured results show good channel isolation, moderate insert losses and small return losses in pass-bands. The diplexer takes a planar form and can be easily integrated in microwave integrated circuits. [ABSTRACT FROM AUTHOR]

A rigorous full-wave approach based on the method of lines (MoL) is presented to analyse the propagation characteristics of substrate integrated waveguides (SIWs), in which a generalised matrix eigenvalue equation is derived instead of the conventional transcend equation, greatly improving the computing efficiency. The use of an efficient Z-transform absorbing boundary condition (Z-ABC) further improved the accuracy of the calculated propagation constants. Finally, two empirical equations are proposed for the propagation constants of SIWs, which gives a simple but efficient tool in designing substrate integrated waveguide components. [ABSTRACT FROM AUTHOR]

The damage to power capacitors caused by harmonic pollution was very serious in recent years due to the wide spread of power electronic related, nonlinear loads. The violent failure of power capacitors may result in power interruption and even accidents in industry. In this paper, a power converter based protection method is proposed for protecting the power capacitor from harmonic damage. A power converter, serially connected to the power capacitor, is used to generate the harmonic components of utility voltage in the proposed method. Hence, the harmonic voltage across the power capacitor is cancelled. It means that the voltage dropped in the power capacitor will be maintained as sinusoidal, despite the waveform distortion of the utility voltage; the current flowing through the power capacitor is then also sinusoidal. Therefore, the power capacitor will not be damaged by the harmonic. A prototype is developed and tested to verify the performance of the proposed method. The test results show that the proposed method has the expected performance. [ABSTRACT FROM AUTHOR]

In the paper, a novel uninterruptible power supply (UPS) is proposed with the performance of input current harmonic suppression, input power factor correction and output voltage regulation. This UPS comprises two power converters, a shunt power converter and a series power converter. The shunt power converter is connected to the utility via a link inductor, for providing a compensating voltage, to suppress the input current harmonic and improve the input power factor. The series power converter is connected serially to the load to provide a clean and regulated output voltage. A voltage-mode control algorithm with fast response and simple control circuit is proposed to control the shunt power converter. The series power converter is controlled by a current-mode control to ensure the quality of output voltage. A single-phase prototype is developed and tested to verify the performance of the proposed UPS. Experimental results show that the proposed UPS has expected performance. [ABSTRACT FROM AUTHOR]

The paper presents a low-cost architecture for a direct conversion digital receiver that uses six-port technology. An experimental prototype has been constructed and tested. Analogue carrier recovery and decision circuits are investigated as a means to provide future system integration and high data rate capacity. The designed receiver is operated at an ISM frequency of 2.45GHz and uses a QPSK modulation format. Results on data rate limitations are given for QPSK signals up to 52Mb/s. Test results related to adjacent channel, co-channel and CW interferences are presented for a data rate of 40Mb/s. Phase offset between carrier and reference signals, along with carrier frequency deviation performances, are also presented for a rate of 40Mb/s. A frequency hopping spread spectrum technique is discussed on the basis of the proposed architecture. [ABSTRACT FROM AUTHOR]

PythagoreanTo date, the design of surface-printed resistors has utilised the time-consuming moment method. The synthetic asymptote technique usually generates simple design formulae, and this technique has been extended and applied to the design of surface-printed resistors. It is found that the derived resistance is immune to change even at high frequencies. In addition, it is found that the novel formula for resistance complies with the Pythagorean nature of trigonometry, which forms a simple basis for synthesis and analysis. In comparison with the moment method solution, it is found that the resistance formula has an error of about 3% for all practical slab dimensions. The synthetic asymptote developed allows designers to rapidly determine the resistance. [ABSTRACT FROM AUTHOR]

Focuses on a spurious mode suppressing technique with an integrated microstrip-to NRD-guide transition and a mode suppressor. Integration scheme of an NRD-guide with a microstrip circuit; Transmission and return losses of optimized transition; Overview of the proposed transition of two dissimilar structures to handle spurious model responses.

Novel design approaches for ultra-high-order subharmonic self-oscillating mixers (SOMs) based on a multiple-element technique are presented. They are of high impact for high-end millimetre-wave systems as subharmonic operation reduces local oscillator frequency requirements. An outline of the basic theory and a design procedure for arbitrary high mixing orders are presented, and a sixth-order SOM is fabricated for the first time. The prototype exhibits a conversion gain of +2.8 dB at an RF input frequency of 7.4 GHz. [ABSTRACT FROM AUTHOR]

The coplanar stripline (CPS) suffers from excessively high characteristic impedance which makes the design of filters difficult. Proposed is a slow-wave rail CPS (R-CPS) transmission line for the design of a stepped impedance lowpass filter. The R-CPS exhibits an extended low-impedance limit not achievable by conventional CPS, while retaining the advantages of the CPS. It also improves the performance of the filter in terms of suppression of the spurious harmonic passbands and reduces the filter size. [ABSTRACT FROM AUTHOR]

A compact filter for ultra-wideband (UWB) applications is proposed and developed through quasi-equal allocation of the first three resonant frequencies of a stub-loaded resonator together with strong input/output excitation. Measured results show low insertion loss and flat group delay in the entire passband as well as a wide stopband. The size for this single-layer UWB filter without feeding lines is only 9.5×5 mm (0.53 λg ×0.28 λg in which λg is the guided wavelength of 50 Ω microstrip at the centre frequency). [ABSTRACT FROM AUTHOR]

A self-equalised pseudo-elliptical filter on the basis of substrate integrated waveguide technology is proposed and demonstrated over the Ka-band range. The extracted-pole technique is used to synthesise a sixth-order filter with non-resonating nodes. Measured results of the filter exhibit a high selectivity and a minimum in-band insertion loss of about 2.0 dB and small inband group delay variation. [ABSTRACT FROM AUTHOR]

A compact multilayer ultra-wideband (UWB) six-port device, composed of power combiners and dividers, is presented. Implemented in hybrid microstip/stripline technology, the six-port can be used as a front-end transceiver. The operational frequency spans a range of 3–5 GHz (50% fractional bandwidth), suitable for pulse signals in UWB single channel communication. Measurements and simulation results validate circuit performance as a transceiver using quaternary phase spectrum modulation. [ABSTRACT FROM AUTHOR]

A BST ferroelectric thin-film microwave phase shifter with interdigital capacitors on TiO2/Si substrate is presented. The interdigital capacitors have 230 µm signal width, 100 µm signal to ground gap, and 10 µm finger gap. The device, with phase shifts of 142° and FoM of 107.3°/dB applied voltage of 50 V at 16 GHz, has been realised. The TiO2 buffer layer grown by ALD enables successful integration of BST-based microwave tunable devices with Si wafer. [ABSTRACT FROM AUTHOR]

The details of a monolithically integrated, five-channel, dual carrier/wavelength per channel, polarisation multiplexed, coherent QPSK receiver on InP operating at 114 Gbit/s per channel are discussed. [ABSTRACT FROM AUTHOR]

A novel super-broadband planar monopulse comparator is presented, and demonstrated experimentally. This comparator is based on a recently discovered 180° hybrid coupler derived from the conventional Wilkinson divider. Because of its symmetric configuration, the proposed comparator exhibits frequency-independent nulls at its three difference output ports and therefore features a quasi unlimited bandwidth. This property substantially enhances the overall broadband resolution performance of monopulse comparators with direct benefits in tracking radar applications. [ABSTRACT FROM AUTHOR]

Proposed is a new substrate-integrated waveguide to air-filled rectangular waveguide (WR-10) transition for use at millimetre-wave frequencies. The transition combines the features of low return loss and low insertion loss over the 42 GHz bandwidth and it can be manufactured without a high degree of complexity. A 75-115 GHz band prototype of the proposed broadband transition is designed and fabricated. Simulated and measured results of the prototyped back-to-back transition show good agreement. [ABSTRACT FROM AUTHOR]

A novel reader loop-type antenna for ultra-high-frequency (UHF) near-field radio frequency identification (RFID) applications is presented. This antenna, printed on a 0.8 mm-thick FR4 substrate with a diameter of 16 cm, is composed of four curved strips and four pairs of coupled stubs, and achieves a wide impedance bandwidth from 840 to 1300 MHz. The proposed structure can make large currents along the loop so that a strong and uniform magnetic field distribution is excited in the region around the antenna. Measurements show that the antenna operating with a commercial reader demonstrates good performance of tag identification with inductive coupling for near-field RFID applications. [ABSTRACT FROM AUTHOR]

The hybrid integration of a dielectric antenna together with an MMIC low-noise amplifier in a 60 GHz front-end is presented. It is demonstrated how a low-loss substrate integrated dielectric antenna can efficiently be interconnected at miniature scale with the coplanar waveguide input of the MMIC. The experimentally obtained return loss is better than 11 dB from 55 to 65 GHz. Transmission path loss measurements of a wireless link confirm the low-loss potential of this approach for millimetre-wave front-ends. [ABSTRACT FROM AUTHOR]

Hot-carrier-induced degradation in an n-type lateral diffused metal-oxide-semiconductor (LDMOS) transistor is investigated. Based on experimental data and technology computer-aided-design simulations, hot-electron injection in the channel region is identified to be the driving force of device degradation. Since gate current (Ig) consists mainly of electron injection, Ig is found to correlate with device degradation well. Such Ig dependent device degradation suggests that Ig should be examined in evaluating the hot-carrier reliability of LDMOS transistors. [ABSTRACT FROM AUTHOR]