a direct conversion modulator-demodulator with even harmonic mixers with emphasis on noise analysis is presented. the circuits consist of even harmonic mixers (ehms) realized with antiparallel diode pairs (apdps). we evaluate the different levels of i/q imbalances and dc offsets and use signal space concepts to analyze the bit error rate (ber) of the proposed transceiver using m-ary qam schemes...

In this paper we describe an interline CCD imaging array which features high-speed, on-chip, parallel A/D conversion. In addition, we present test results from fabricated devices. The imaging chip was fabricated through MOSIS in a double-poly 2:0m CCD/CMOS technology on a chip with total area 2:25mm 2:22mm. The chip is composed of two components, namely, a 28 39 pixel, interline imaging array a...

A compact integrated antenna with direct quadrature conversion circuitry for broad-band millimeter-wave communications is proposed. The conversion circuits include two even-harmonic mixers based on antiparallel diode pairs (APDPs). The equivalent circuit of the APDP derived here provides good agreement with the measured data from 17 to 23 GHz. Overall phase and amplitude imbalance between the i...

A low power, wideband transmitter architecture utilizing ∆Σ direct digital modulation of an RF carrier is presented. Spurious signals associated with direct digital-RF conversion are eliminated through integration of a self-tuned passive LC bandpass filter. The digital-RF modulator is intended for OFDM systems and can provide data rates greater than 1 Gb/s using a bandwidth of 200 MHz centered ...

This paper describes calibration techniques for downconversion mixers used in integrated direct-conversion receivers. A method of achieving a high even-order intermodulation rejection is presented. Using the method presented, the receiver second-order input intercept point (IIP2) can always be improved by more than 20 dB. The minimum achieved receiver IIP2 after calibration is +38 dBm. A techni...

Initial historical accounts as well as recent data suggest that emotion processing is dysfunctional in conversion disorder patients and that this alteration may be the pathomechanistic neurocognitive basis for symptoms in conversion disorder. However, to date evidence of direct interaction of altered negative emotion processing with motor control networks in conversion disorder is still lacking...

A single-chip, multi-mode receiver for GSM900, DCS1800, PCS1900, and UTRA/FDD WCDMA is introduced in this paper. Hence, the receiver operates at four different RF frequencies with two different baseband bandwidths. The presented chip, which consists of a low noise amplifier, downconversion mixers with on-chip LO I/Q-generation, channel selection filters, and programmable gain amplifiers, uses a...

A high-conversion-rate high-resolution oversampling digital-to-analog converter (DAC) for direct digital modulation is addressed in this paper. A new type of switching scheme, called differential-quad switching, is presented. To verify the feasibility of this scheme, essential parts with some auxiliary circuitry for interfacing were fabricated in a 0.8m CMOS technology. Measured results show th...

The strong development in producing neurons ready for transplantation has been widely documented, from directed differentiation of human embryonic stem cells to the direct conversion from skin cell to brain cell. However, tools for measuring the transplanted cells ability to connect to the synaptic circuitry in the host brain has been unsatisfactory. The new task force aims to use the unique qu...