Hiroyuki Mizutani

A Planar Image Rejection Mixer with 135/45 deg Power Dividers

A planar image rejection mixer (IRM) with power dividers which have phase differences is presented. The 135 and 45 deg of the phase differences give high image rejection ratio and high LO-RF port isolation. Since this IRM consists of only planar circuits without the crossover between LO and RF lines, it is suitable for discrete configuration. The fabricated IRM with 135/45 deg power dividers has achieved -20 dB of image rejection ratio and 30 dB of LO-RF port isolation over the frequency range from 1.85 GHz to 2.9 GHz.

A high-speed mobile OFDM receiver LSI with an iterative noise-reduction filter to enhance channel estimation

This work presents an OFDM receiver LSI with an iterative noise-reduction filter. Experimental results show that the LSI drastically improves the mobile reception performance, especially in high-speed environments. The die is fabricated with 0.18 um CMOS process, including ADC, DAC, and PLL.

Evaluation of diversity combining systems for mobile reception in Digital Terrestrial Television Broadcasting

In this paper, we evaluated the mobile reception performance of ISDB-T receivers using scalable OFDM diversity LSIs. The receivers exploit two kinds of diversity schemes which are time-domain based array antenna (AA) and frequency-domain based carrier diversity (CD). The reception performance of some diversity systems is evaluated by laboratory and field experiments. According to the results, 4ch-CD achieves the highest performance under fading channels. Also, the performance of 4ch-AA is almost as high as that of the 4ch-CD in receiving high-correlated signals, being much better than that of 2ch-CD.

The Implementation of a 2/4/8 Antennas Configurable Diversity OFDM Receiver for Mobile HDTV Application

Two array antennas and one carrier diversity combiners are integrated with Japan Terrestrial digital TV (ISDB-T) OFDM receiver using 90 nm 7M1P CMOS process. A 2/4/8 antennas diversity receiver can be configured and the low cost 4 antennas diversity reception system can be realized by one LSI. The mobile reception performance is increase by 63% using de-noise filter circuit and SPLINE interpolator. The die area is 49 mm2 and the power consumption is 310 mW.

A 2/4/8 antennas configurable diversity OFDM receiver for mobile HDTV Application

Two array antennas and one carrier diversity combiners are integrated with Japan Terrestrial digital TV (ISDB-T) OFDM receiver using 90 nm 7M1P CMOS process. A 2/4/8 antennas diversity receiver can be configured and the low cost 4 antennas diversity reception system can be realized by one LSI. The mobile reception performance is increase by 63% using de-noise filter circuit and SPLINE interpolator. The die area is 49 mm2 and the power consumption is 310 mW.