An LDMOS VHF class-E power amplifier using a high-Q novel variable inductor

In this paper, an lateral diffused metal-oxide-semiconductor-based very high-frequency class-E power amplifier has been investigated theoretically and experimentally. Simulations were verified by amplifier measurements and a record-high class-E output power was obtained at 144 MHz, which is in excellent agreement with simulations. The key of the results is the use of efficient device models, simulation tools, and the invention of a novel high-Q inductor for the output series resonance network. The latter allows for low losses in the output network and, simultaneously, a wide tuning range for maximum output power or maximum efficiency optimization

C-Band Resistive SiC-MESFET mixer

In this paper the design and characterization of a linear C-band single ended resistive SiC-MESFET mixer is presented. The mixer has a minimum conversion loss of 7.8 dB and has a third order intermodulation intercept point of 30.3 dBm. The mixer is designed using a harmonic-balance simula-tion load-pull approach. This design method is especially use-ful for high-level mixers, where small-signal approximations cannot be used

Calculation of the Performance of Communication Systems from Measured Oscillator Phase Noise

Oscillator phase noise (PN) is one of the major problems that affect the performance of communication systems. In this paper, a direct connection between oscillator measurements, in terms of measured single-side band PN spectrum, and the optimal communication system performance, in terms of the resulting error vector magnitude (EVM) due to PN, is mathematically derived and analyzed. First, a statistical model of the PN, considering the effect of white and colored noise sources, is derived. Then, we utilize this model to derive the modified Bayesian Cramer-Rao bound on PN estimation, and use it to find an EVM bound for the system performance. Based on our analysis, it is found that the influence from different noise regions strongly depends on the communication bandwidth, i.e., the symbol rate. For high symbol rate communication systems, cumulative PN that appears near carrier is of relatively low importance compared to the white PN far from carrier. Our results also show that 1/f^3 noise is more predictable compared to 1/f^2 noise and in a fair comparison it affects the performance less.Comment: Accepted in IEEE Transactions on Circuits and Systems-I: Regular Paper

A QFN packaged grid array antenna in low dielectric constant LTCC for D-band applications

International audienceA medium-gain Grid Array Antenna (GAA) is developed and manufactured in ESL41110, a low εr Low Temperature Co-fired Ceramics (LTCC) from ElectroScience Laboratory. The antenna dimensions are 12 mm × 12 mm × 0.3 mm and it has a measured impedance bandwidth from 135 to 142 GHz, with a boresight maximum gain of 7.96 dBi and vertical beams. In order to realize this antenna, new LTCC fabrication steps had to be developed and qualified in the in-house procedure, including laser ablation of gold in the green state as well as after sintering

High linear power amplifier for multicarrier satellite communications

High linearity performance in transmitters is receiving continuously attention due to demands of higher data rates in satellite communication links. This paper presents a GaAs pHEMT MMIC high linear power amplifier intended for multicarrier operation at C-band. Junction temperature prediction methods are considered during the amplifier design to keep the temperature under control and achieve high reliability required for space applications. The design method is focused in high linearity optimizing the loads and using a non-linear transistor model to predict harmonic generation and intermodulation products. The amplifier was characterized in terms of S-parameters, single tone output power and two tone output power. The measured S-parameters shows a flattened gain over 25 dB between 3 and 6 GHz. The 1dB compression point is measured at 26.7 dBm and the output third order intercept point (OIP3) is above 40 dBm in the band reaching a maximum of 41.7 dBm at 4.5 GHz. The power consumption is lower than 2.5 W and the junction temperatures are calculated under 105 \ub0C

A Direct Carrier I/Q Modulator for High-Speed Communication at D-Band Using 130 nm SiGe BiCMOS Technology

This paper presents a 110-170 GHz direct conversion I/Q modulator realized in 130 nm SiGe BiCMOS technology with ft/fmax values of 250 GHz/ 370 GHz. The design is based on double-balanced Gilbert mixer cells with on-chip quadrature LO phase shifter and RF balun. In single-sideband operation, the modulator exhibits up to 9.5 dB conversion gain and has measured 3 dB IF bandwidth of 12 GHz. The measured image rejection ratio and LO to RF isolation are as high as 20 dB and 31 dB respectively. Meas-ured input P1dB is -17 dBm at 127 GHz output. The DC power con-sumption is 53 mW. The active chip area is 620 μm× 480 μm in-cluding the RF and LO baluns. The circuit is capable of transmit-ting more than 12 Gbit/s QPSK signal

A low noise 2-20 GHz feedback MMIC-amplifier

A low noise feedback MMIC-amplifier based on a 180 GHz f(max) PHEMT-technology is described. The gain input and output reflection coefficient, de-power consumption, and noise parameters are investigated theoretically and experimentally as a function of dc-bias and frequency. The noise figure is typically 2.5 dB with an associate gain of 22 dB across the 2-20 GHz frequency range. The circuit area is less than 1 mum(2) and the de-power consumption is lower than 100 mW

A Fully integrated D-band Direct-Conversion I/Q Transmitter and Receiver Chipset in SiGe BiCMOS Technology

This paper presents design and characterization of single-chip 110-170 GHz (D-band) direct conversion in-phase/quadrature-phase (I/Q) transmitter and receiver monolithic microwave integrated circuits (MMICs), realized in a 130 nm SiGe BiCMOS process with ft/fmax of 250 GHz/370 GHz. The chipset is suitable for low power wideband communication and can be used in both homodyne and heterodyne architectures. The Transmitter chip consists of a six-stage power amplifier, an I/Q modulator, and a LO multiplier chain. The LO multiplier chain consists of frequency sixtupler followed by a two-stage amplifier. It exhibits a single sideband conversion gain of 23 dB and saturated output power of 0 dBm. The 3 dB RF bandwidth is 31 GHz from 114 to 145 GHz. The receiver includes a low noise amplifier, I/Q demodulator and x6 multiplier chain at the LO port. The receiver provides a conversion gain of 27 dB and has a noise figure of 10 dB. It has 3 dB RF bandwidth of 28 GHz from 112-140 GHz. The transmitter and receiver have dc power consumption of 240 mW and 280 mW, respectively. The chip area of each transmitter and receiver circuit is 1.4 mm x 1.1 mm

An ultrawideband microwave medical diagnostic system: Design considerations and system performance

We discuss several issues in the design of an ultra-wideband microwave system dedicated to medical diagnostics. Based on the discussion, a FPGA-based time domain microwave diagnostic system is proposed. The noise sources of the system are identified and the system noise performance is analyzed. As an example, a 2-D antenna system is considered and the measurement signal to noise ratios are evaluated

Accuracy Evaluation of Ultrawideband Time Domain Systems for Microwave Imaging

We perform a theoretical analysis of the measurement accuracy of ultrawideband time domain systems. The theory is tested on a specific ultrawideband system and the analytical estimates of measurement uncertainty are in good agreements with those obtained by means of simulations. The influence of the antennas and propagation effects on the measurement accuracy of time domain near field microwave imaging systems is discussed. As an interesting application, the required measurement accuracy for a breast cancer detection system is estimated by studying the effect of noise on the image reconstructions. The results suggest that the effects of measurement errors on the reconstructed images are small when the amplitude uncertainty and phase uncertainty of measured data are less than 1.5 dB and 15 degrees, respectively