A configuration of antenna using flexible substrate for RF energy harvesting system working at GSM frequency 1800 MHz is presented. The suspended structure is used to surpass the high loss of the substrate. By taking advantage of the flexible properties, the process of miniaturization is achieved through folding the substrate into sections. The antenna prototypes were fabricated and measured. With the compact size of 0.36 λ × 0.33 λ × 0.03 λ, the measured gain is 5.3 dB, about 10 dB gain increase compared to conventional structure.

A new configuration of an antenna with adjustable frequency is presented. The principle of aperture coupled microstrip antenna is used. The patch antenna is printed on flexible material and can easily be stuck or removed from the outside of a circuit packaging to alter its resonant frequency while the feed network and the connected circuit are unaffected inside. This type of antenna can be used in the application of Radio-frequency (RF) energy harvesting which is strongly dependent on frequency of radiated waves in the vicinity of the antenna. The design for an antenna operating at three frequencies 1800 MHz, 1900 MHz and 2.4 GHz is proposed. Simulated and measured results are both presented, with promising prospects.

In this letter, we present an innovative solution to achieve high efficiency printed antennas made on paper substrate. A corrugated cardboard is introduced for the first time for RF circuits. This substrate has been characterized with small perturbation method. It presents a dielectric constant of 1.41 and loss tangent of 0.042. Subsequently, patch antennas were realized on corrugated cardboard and classical paper substrate. A measured gain of 5.12 dBi is reached with corrugated cardboard compared to -3.24 dBi for classical paper. Simulation results show a good agreement with measurement.

The aim of this paper is to present an ESD solution to address several challenges. The first challenge is to obtain a robust ESD protection with symmetrical response under +/- 1 kV HBM. And the second one is to reach 100 GHz broadband for RF application. These targets are reached thanks to the BIMOS transistor and dual back to back SCR solution, both compatible with advanced CMOS technology. Moreover, the silicon area and leakage constraints are also addressed. The study is performed through the 3D TCAD simulation and RF models on 40 nm and 32 nm. It also includes Transmission Line Pulse (TLP) and S parameters measurements to characterize and qualify this design and topology. (C) 2013 Elsevier Ltd. All rights reserved.

This b paper describes theoretical study, modeling and simulation of tunable coupled line phase shifter. This structure is based on basic Schiffman model in which a coupled dispersive microstrip transmission line was used combined with uniform transmission line. The main idea of this work is to design a mixed structure of tunable phase shifter loaded by Varactor diode. A differential phase between two paths of transmission signal was created and tuned using variable capacitance, this phase keeps approximately the same value on the operating frequency band between 0.8 and 1.4GHz. We have evaluated the performances and good variation of phase shifting was denoted with good insertion loss, less than 1.0dB and return losses for both of two signal paths.

This paper describes how to design a printed on paper antenna. The extraction of the electrical parameters of the substrate as well as the conductive ink is needed to design the antenna. The antenna was then fabricated and characterized. It operates at the center frequency of 2.45GHz. It exhibits an efficiency of 72%.

This paper presents new study and design of microstrip phased array antennas used for extending the coverage area of RFID applications (ISO 18000-4 for 2.45GHz). The main idea is to modifying the antenna radiation pattern in order to extend the coverage area. The principle element achieving this operation is a distributed phase shifter. We have designed a patch antenna working at 2.45GHz and used it to build an antenna array. The antenna beam steering was achieved by implementing RF distributed phase shifter to excite the radiating elements of the antenna array. Distributed phase shifters are designed to provide the required phase shift to change the array pattern without disturbing the system performances.

Radiofrequency transmission circuits are going towards integration of all functions including filters. In this domain, acoustic filters using Surface Acoustic Waves (SAW) or Bulk Acoustic Waves (BAW) are being studied increasingly and in particular advanced structures such as Coupled Resonator Filter (CRF). A wide band modeling of the complete CRF filter is proposed. This model is compared to simulation and the limitation of RF pads necessary for characterization is highlighted. Adding to the simulation the measurement of single RF pads validates this assumption. Another problem is the industrial test of all filters after fabrication. Usually, frequency domain characterizations are performed. Nevertheless, this method is time consuming, needs expensive equipment and is not suitable for industrial testing. A new method of filter characterization is proposed using a digitally modulated signal where the carrier frequency is chosen close to the central frequency of the filter. Then, at the filter output, Error Vector Magnitude (EVM) is analyzed. This EVM gives us information on the filter behavior and presents good agreements with simulations. In fine, these results are compared to S-parameters to validate the new proposed method.

This paper presents a study, optimization and simulation of tunable bandpass filter centered at 2.4GHz and used as phase shifter based on coupled microstrip square ring loaded by varactor diodes. We have performed an electromagnetic simulation on Momentum software of ADSTM; we have used the power of the Momentum software for the optimization and simulation of our circuit. A good results were obtained; the filter results in an insertion loss of 0.35 dB−0.26 dB over tuning range and 3−dB b andwidth o f 3 00MHz−360MHz. W e c ompute a f ractional bandwidth between 13% and 14.5% for our circuit and for different value of capacitance. We compute also a good dynamic range of phase shifting about 90° at operating frequency 2.4GHz for different value of capacitance.

A reliability study under DC stress has been conducted on a low noise amplifier (LNA), a mixer and a voltage controlled oscillator (VCO). Both mmW blocks were designed with heterojunction bipolar transistor (HBT) 0.13μm SiGe process from STMicroelectronics. Regarding simulations and HBT degradation studies, DC stresses were defined to provide HBT degradation within the mmW blocks. S parameters were characterized for the LNA; conversion gain and low frequency noise (LFN) were measured for the mixer; oscillation frequency and phase noise were respectively characterized and simulated. LNA and mixer are designed for 77 GHz automotive radar applications and the VCO is designed for 60 GHz wHDMI standard. Limited degradations on mmW blocks characteristics were observed for significant stress conditions covering a time to fail (TTF) of 10years.

The nonlinear behavior of Coupled Resonator Filters (CRF) is studied in time and frequency domains. 1 dB-compression point and/or Intermodulation Products (IMD) are both frequency-dependent parameters and thus, they can not be used to study simultaneously the nonlinearities in time and frequency domains. The proposed characterization method consists on sending a digitally modulated signal (QPSK) through CRF devices with RF carrier frequency sweeping the filter band-pass at high power levels. Two spectral occupancies of QPSK signal can be used covering whether a narrowband of 8% (WCDMA single channel bandwidth) or a wideband of 40% of the filter bandwidth. The signal received at CRF output provides two response types: a system-parameter as the Error Vector Magnitude (EVM) and transmission S-parameter. Measurements are carried out at CRF's 1 dB-compression point of 40 dBm Results show EVM variations of 4% and 1% respectively for narrow and wide spectral occupancy. We observe also a transmission phase shifting going to 10° in the band-pass for 1 dB magnitude decrease.

This paper describes theoretical study, modeling and simulation of tunable coupled line phase shifter. This structure is based on basic Schiffman model in which a coupled dispersive microstrip transmission line was used combined with uniform transmission line. The main idea of this work is to design a mixed structure of tunable phase shifter loaded by Varactor diode. A diffrential phase between two paths of transmission signal was created and tuned using variable capacitance about 0.1 to 3.0pF, this phase keep aproximatly the same value on the operation frequency band between 0.8 to 1.4GHz. We have evaluated the performances and good variation of phase shifting was denoted with good insertion loss, less than 1.0dB and return losses for both of two signal paths. KeywordsCoupled Line; Tunable; Phase shifter; Schifman; Varactor diode

This paper presents the modeling of phase shifter based on distributed CPW transmission lines combined with SMD components. It presents an analytical study of the phase shifting, the insertion loss and the return loss of proposed phase shifter. The expression of phase shifting is obtained through a global ABCD matrix of 9-sections of proposed phase shifter.

This paper presents high Q and high current on-chip inductors manufactured in an innovative Radio Frequency (RF) Back End Of Line (BEOL), made of two 3 mum thick top copper levels, integrated in an Advanced Low Power 65 nm RF CMOS technology. Achieved inductors using this optimized RF BEOL are firstly reported, compared with those using one single thick copper level BEOL, and benchmarked with current ones fabricated in a standard CMOS BEOL. According to measurement results, reported inductors offer quality factor Q greater than 22 and current capability I max up to 20 mA/mum @ 125degC, performances suitable for RF power applications.

The development of radiofrequency transmission systems is going towards integration of all functions including filtering. In this domain, filters using BAW (bulk acoustic wave) resonators are being studied increasingly in advanced structures such as coupled resonator filter (CRF). The industrial testing of these devices, and generally the test of analog components, remains an unexplored field. A new method for testing the devices using a VNA is proposed. The main idea is to reduce the time that the characterization of a filter requires. The solution specifies a limited number of points that could characterize the filters. For this purpose a series of filters was characterized and the method was validated on 5 to 11 measured points. This procedure defines the number of points requested to discriminate the defected filters. As a final step, simulations are done using an electrical model in broadband; this approach gives physical information of the measurements and contributes to build a library of defected filter models.