4 research outputs found
Cryogenic W-Band SiGe BiCMOS low-noise amplifier
In this paper we present the design, modeling, and on-wafer measurement results of an ultra- wideband cryogenically cooled SiGe low-noise amplifier covering at least 71 to 116 GHz. When cryogenically cooled to 20 K and measured on wafer the SiGe amplifier shows 95-116-K noise temperature from 77 to 116 GHz. This means 6 to 7 times improvement in noise temperature compared to room temperature noise. The measured gain is around 20 dB for frequency range of 71 to 116 GHz with unprecedented low power consumption of 2.8 mW. To the best of authors' knowledge, this is the highest frequency cryogenic SiGe low-noise amplifier and lowest noise performance for silicon amplifiers for W-band reported to date
Design of MMIC W-band Low Noise Amplifier and Its Characterization for Cryogenic Temperatures
HEVC (H.265) Intra-Frame prediction implementation Using MATLAB
HEVC (H.265) standard is the latest enhanced video coding standard which was planned to improve the rendered specifications of its preceding standard MPEG-4 (H.264). According to the H.265 “The main goal of the HEVC standardization effort is to enable significantly improved compression performance relative to existing standards—in the range of 50% bit-rate reduction for equal perceptual video quality” [2]. Intra-picture prediction is a tool in HEVC which “uses some prediction of data spatially from region-to-region within a specific picture, but has no dependence on other pictures in the video frames” [2]. Intra-picture prediction of HEVC is the legacy of intra-frame prediction tool in H.264. Although both of them has the same approach in for spatial prediction of pictures based on spatial sample prediction followed by transform coding, H.265 intra-frame prediction uses much more developed features compared to H.264. An overview of the main features in intra-frame prediction of H.265 could be written as follows: A quad-tree block division structure with respect to amount of details in an image 33 Angular modes in angular prediction (just 8 different modes in H.264) Planar prediction for smoothing the sample surfaces [2] It’s worth mentioning that the quad-tree structure of H.265 intra normally uses square block with sizes in range 4, 8, 16, 32 and 64 (different block sizes based-on the level of granularity in the image), while in H.264 the processing units are up to macro-blocks of 16x16 samples. Moreover, while this video coding standard splits images to one luma and two chroma parts, thesis focuses only on the implementation of intra-prediction on luma part of an image. This thesis aims at implementation of the intra-frame prediction of HEVC using MATLAB. All the steps of implementation process are listed as follows: Converting RGB images to YUV colour-space and working on the luma part (or Y) Splitting images to square blocks ranging from 4 to 64 pixels Implementing intra-frame prediction algorithm Comparing intra-prediction output of H.264 and H.265 in square blocks with size 4 and 16 pixels This Thesis is organised in 3 main sections. The first and second sections revolve around literature review and definition of the concept of HEVC standard and intra-prediction respectively. The third section focuses on the implementation process and evaluation of the prediction algorithm. Finally, in the evaluation part, based-on statistical graphs derived from the output comparison of H.264 and H.265 intra-prediction for different images, it has been demonstrated that H.265 by far has a better image quality than of the H.264
Cryogenic W-Band SiGe BiCMOS Low-Noise Amplifier
In this paper we present the design, modeling, and on-wafer measurement results of an ultra- wideband cryogenically cooled SiGe low-noise amplifier covering at least 71 to 116 GHz. When cryogenically cooled to 20 K and measured on wafer the SiGe amplifier shows 95-116-K noise temperature from 77 to 116 GHz. This means 6 to 7 times improvement in noise temperature compared to room temperature noise. The measured gain is around 20 dB for frequency range of 71 to 116 GHz with unprecedented low power consumption of 2.8 mW. To the best of authors' knowledge, this is the highest frequency cryogenic SiGe low-noise amplifier and lowest noise performance for silicon amplifiers for W-band reported to date