M. Hirata

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This paper presents an OFDM transceiver for wireless LAN systems and its baseband transceiver architecture. TYPICAL PARAMETERS IN PACKET-ORIENTED OFDM SYSTEMS. We study the optimum parameters about DFT size, guard K DFT size interval, symbol duration, and number of subcarriers in an 80-Fb Bandwidth (Hz) MHz bandwidth by extending the IEEE802.11a standard.(More)
PURPOSE We compared the image quality of SPACE (sampling perfection with application optimized contrasts using different flip angle evolutions) and conventional 3D turbo spin echo (TSE) magnetic resonance cholangiopancreatography (MRCP) at 1.5 tesla with regard to difference in echo spacing. METHODS Twenty healthy volunteers prospectively underwent(More)
This paper presents an iterative image reconstruction method for radial encodings in MRI based on a total variation (TV) regularization. The algebraic reconstruction method combined with total variation regularization (ART_TV) is implemented with a regularization parameter specifying the weight of the TV term in the optimization process. We used numerical(More)
To realize a low-invasive and high accuracy BMI (Brain-machine interface) system, we have already developed a fully-implantable wireless BMI system which consists of ECoG neural electrode arrays, neural recording ASICs, a Wi-Fi based wireless data transmitter and a wireless power receiver with a rechargeable battery. For accurate estimation of movement(More)
In follow-up brain magnetic resonance imaging (MRI), precise reproducibility of the scan prescription is important so that over- or underestimating changes in volumes of clinical interest is prevented. (The scan prescription is defined as the location and orientation of the head with respect to the scan planes of the three-dimensional MRI matrix.) In this(More)
PURPOSE To assess the ability of magnetic resonance imaging (MRI) to depict the semicircular canals of the inner ear by comparing results from the sampling perfection with application-optimized contrasts by using different flip angle evolutions (SPACE) sequence with those from the true free induction with steady precession (TrueFISP) sequence. MATERIALS(More)
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