A 90nm CMOS, 64Kbit, 1.16GHz, 16 port SRAM with multi-bank architecture realizing 590Gbps random access bandwidth, 41mW power dissipation at 1GHz and 0.91mm2 (13.9µm2/bit) area consumption is reported. Compared to conventional 16 port SRAM data, area and power consumption are reduced by factors 16 and 5, respectively, while maximum clock frequency is about a factor 2 higher.
We developed a microscopic electro-optic field probe by directly depositing a lead zirconate-titanate [PbZr0.3Ti0.7O3] film onto the optical fiber edge using aerosol deposition. Its fabrication process is low-cost and relatively easy because there are no complicated procedures such as fine lithography and etching. The lateral size of the film is 125µm, which is the same as the diameter of a typical single mode fiber, and the thickness is approximately 5µm. An RF electro-optic signal was successfully measured over a microstrip line. The capability for detecting GHz range fields is also shown. Because it is very tiny and thin, the developed electro-optic probe has great potential for detailed electrical characterization in the microscopic regions of high performance electronic products such as the interconnecting parts between LSI packages and printed circuit boards and spaces among different LSI chips in a package.
In a transmission system, the conventional adaptive blind equalizers are implemented a direct estimation for the parameters of the equalizers. But both convergence rate of these algorithms and reliability of the regenerated signals degrade down. In this paper, we propose a new equalization system and a new adaptive algorithm using the blind channel estimation for improving these two faults above. In the proposed method, first, we provide a psudo-channel and input signals to the psudo-channel in received part, and characteristics of the channel are adaptivly estimated using simplified kurtosis, skewness of output signals of the channel and the psudo-channel. Secondly, we design the equalizer using an adaptive orthogonal projection algorithm for the estimated channel impulse response matrix. We confirm that convergence rate of the proposed algorithm and reliability of the regenrated signals are better than those of the conventional adaptive blind algorithm by numerical example.
This letter presents a new design method of a low-power transmitter for inductive link. The proposed method introduces the concept of class-F RF amplifiers into an inductive data link. The power dissipation of the class-F transmitter is analyzed for carrier and symbol transition. It is revealed that the proposed transmitter consumes extremely low power of less than 0.2nJ/bit with BPSK modulation at 2.5M Sample/s and the communication distance of about 50cm.
A millimeter-wave CMOS on-chip stacked Marchand balun is presented in this paper. The balun is fabricated using a top pad metal layer as the single-ended port and is stacked above two metal conductors at the next highest metal layer in order to achieve sufficient coupling to function as the differential ports. Strip metal shields are placed underneath the structure to reduce substrate losses. An amplitude imbalance of 0.5dB is measured with attenuations below 6.5dB at the differential output ports at 30GHz. The corresponding phase imbalance is below 5 degrees. The area occupied is 229µm × 229µm.
This letter proposes a spectrum delivery function in distributed antenna system (DAS) using Radio on Free Space Optics (RoFSO) for indoor wireless local area network (WLAN). RoFSO can transfer various kind of radio services on optical wireless carrier, and spectrum delivery function realizes efficient utilization of radio frequency (RF) resources. Numerical calculations show that the improvement in throughput performance can be obtained when users are locally concentrated, and RF resources are fairly used in terms of fairness index.
We propose a bit-shifting-based fuzzy inference method for an efficient digital hardware implementation. The proposed fuzzy inference method includes two new techniques which are a membership function generating method and a fast defuzzification method using only “active units”. These techniques reduce a hardware cost and a calculation cost for the membership function and the defuzzification, respectively. In this paper, we apply the proposed method to an execution mode of self-organizing relationship network. Simulation results show that the proposed method has a good approximation ability of a nonlinear I/O relationship as well as the ordinary method.
In active noise control (ANC) systems, the online secondary path modeling (OSPM) methods that use additive random noise are often applied. The additive random noise, however, contributes to the residual noise, and thus deteriorates the noise control performance of ANC systems. This paper proposes a new OSPM method with power scheduling of additive random noise. Here the OSPM filter is adapted using a variable step size (VSS) LMS algorithm already proposed by authors. Furthermore, the additive-random-noise power is scheduled based on the convergence status of an ANC system. Computer simulations demonstrate the effectiveness of the proposed method.
This paper analyzes sound pressure field profiles formed by a conical acoustic probe (CAP) with a pinhole much smaller than the ultrasonic wavelength λ. The analysis is done using the Rayleigh integral and the finite element method (FEM). Both calculated results reveal that lateral -3dB widths near the pinhole are approximately equal to the pinhole diameter and that the shape of the CAP does not affect the lateral width. A lateral resolution of the CAP, which is much smaller than λ, is verified by our analysis.