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An artificial magnetic conductor (AMC) applied in millimeter wave on chip antenna design based on a standard 0.18 μm CMOS technology is studied. The AMC consisting of two-dimensional periodic dogbone shape elements is constructed at one metal layer of the CMOS structure. After its performance has been completely investigated, it has been used in an on chip dipole antenna design as an artificial background to enhance efficiency of the dipole antenna. The result shows that 0.72 dB gain has been achieved at 75 GHz when the AMC is constructed by a 4*6 dogbone array.

The nanoboron carbide particle size is 60nm, dispersed in RO reverse osmosis membrane treatment water form water-based nanofluid by adding the dispersant. In experiment, Water-based nanoboron carbide fluid has good resistance sedimentation stability when adding sodium carboxymethyl cellulose as a dispersing agent. Prepared three kinds of water-based nanoboron carbide fluid, the mass fraction of nanoparticles is 0.6%, 0.8%, 1.0%. By establishing a model of U-shaped tube, simulated the water-based nanofluids flow field in U-shaped tube using FLUENT, get velocity flow lines picture and pressure variation graph by CFD post-processing. From simulation results obtained: Water-based nanoboron carbide has good transmission fluid performance when nanoparticles mass fraction of 0.8%.

A fully integrated K-band dual down-conversion receiver for phased array radar applications in 90 nm CMOS is presented. The receiver utilizes the dual down-conversion architecture to achieve superior performance. The integrated 1.15 GHz image-rejection filter (IRF) provides enough wideband (22 MHz) image rejection ratio at 140 MHz offset before the second down-conversion by utilizing the Q-enhancing and frequency staggering techniques to compensate the component loss. The low noise amplifier realizes the single-to-differential-ended conversion at the input with a transformer and achieves good common-mode rejection. The 70 MHz intermediate frequency baseband consists of two cascaded 3rd-order band-pass active-RC filters (BPFs) and one automatic gain control (AGC) loop, with the integrator frequency compensation technique to lower down the requirements on the embedded Op-Amps. Two phase-locked loop (PLL) frequency synthesizers are integrated to provide the local oscillation (LO) signals for the down-conversions, where the matching of the charge-pump is improved by adding one extra current compensation branch. The measurements of the prototype show that the receiver converts the targeted mm-wave signal to 70 MHz intermediate frequency while achieving 8.3 dB noise figure (NF), 51-95 dB variable gain range and >45 dB image rejection ratio at 140 MHz offset with >22 MHz signal bandwidth. The receiver draws 74 mA current (excluding 2 PLLs) from the 1.2 V power supplies and occupies a core area of 4.58 × 0.53mm 2 (excluding 2 PLLs).INDEX TERMS Dual-conversion receiver, image rejection filter, wireless receiver, band-pass filter, automatic gain control loop (AGC), CMOS.