36 research outputs found

    Design and Implementation of an RF Front-End for Software Defined Radios

    Get PDF
    Software Defined Radios have brought a major reformation in the design standards for radios, in which a large portion of the functionality is implemented through pro­ grammable signal processing devices, giving the radio the ability to change its op­ erating parameters to accommodate new features and capabilities. A software radio approach reduces the content of radio frequency and other analog components of the traditional radios and emphasizes digital signal processing to enhance overall receiver flexibility. Field Programmable Gate Arrays (FPGA) are a suitable technology for the hardware platform as they offer the potential of hardware-like performance coupled with software-like programmability. Software defined radio is a very broad field, encompassing the design of various technologies all the way from the antenna to RF, IF, and baseband digital design. The RF section primarily consists of analog hardware modules. The IF and baseband sections are primarily digital. It is the general process of the radio to convert the incoming signal from RF to IF and then IF to baseband for better signal processing system. In this thesis, some of major building blocks of a Software defined radio are de­ signed and implemented using FPGAs. The design of a Digital front end, which provides the bridge between the baseband and analog RF portions of a wireless receiver, is synthesized. The Digital front end receiver consists of a digital down converter(DDC) which in turn comprises of a direct digital frequency synthesizer (DDFS), a phase accumulator and a low pass filter. The signal processing block of the DDFS is executed using Co-ordinate Rotation Digital Computer (CORDIC) iii Abstract algorithm. Cascaded-Integrator-Comb filters (CIC) are implemented for changing the sample rate of the incoming data. Application of a DDC includes software ra­ dios, multicarrier, multimode digital receivers, micro and pico cell systems,broadband data applications, instrumentation and test equipment and in-building wireless tele­ phony. Also, in this thesis, interfaces for connecting Texas Instruments high speed and high resolution Analog-to-Digital converters (ADC) and Digital-to-Analog converters (DAC) with Xilinx Virtex-5 FPGAs are also implemented and demonstrated

    Present status of marine fisheries of Tamil Nadu and Pondicherry

    Get PDF
    The exploited fisheries of Tamil Nadu and Pondicherry during the recent five year period 1985-'89 have been studie

    Appraisal on the marine fishing craft and gear of the Indian coast

    Get PDF
    The use of fishing methods varying from simple traps to large trawlers and from hand lines to sophisticated purse seines is a typical feature of marine fisheries in India. The regional and seasonal variation is so vast that the developmental agencies and administrative machinery are often handicapped in deciding priorities on modernizing the traditional tools. A document as attempted here, would form a piece of vital information for the R&D agencies. The traditional gear operated in different regions of the Indian coast are classified based on the mode of operation and an exhaustive listing along with local names is attempted. Besides, contributions to the marine fish production separately by traditional and modern craft are brie flu noted

    Not Available

    No full text
    Not AvailableThe exploited fisheries of Tamil Nadu and Pondicherry during the recent five year period 1985-'89 have been studiedNot Availabl

    An Unusual Cause of Double Duct Sign

    No full text

    Oil that spoils the child

    No full text

    Application of embryonic equivalents in male-to-female sex reassignment surgery

    No full text
    Introduction: The feeling of incongruence between phenotypic sex and psychological recognition of self-gender is termed gender dysphoria. Transsexualism is the most extreme form of this disorder. Aims and Objectives: The aims and objectives of the study are to evaluate the esthetic and functional outcome of embryonic equivalents-based male-to-female sex reassignment surgery in transwomen using the institutional scoring system. Materials and Methods: Thirty transwomen who had undergone male-to-female embryonic equivalents-based sex reassignment surgery (MFEEbSRS) from October 2012 to March 2016 were retrospectively studied. The outcome was evaluated by two independent plastic surgeons, based on interview with the individuals, visual assessment, and measurements. Surgical Technique: Clitoris was created from reduced glans on dorsal penile pedicle mounted on the crura of the conjoined corpora cavernosa. De-gloved unfurled proximal penile skin formed the introitus, hood for clitoris and labia minora. Neo-external urethral meatus was fashioned from the distal portion of the bulbar urethra. Distal de-gloved inverted penile tube flap was used for the creation of neovagina. Reduced scrotal flaps formed the labia majora. Observation and Results: The maximum length of neovagina in the study was 12 cm, and the average length was 9.8 cm. Based on our institutional scoring system for the assessment of esthetic and functional outcome, we got excellent results in all transwomen. Conclusion: The esthetic and functional outcome in all the patients was good. All patients were relieved of their primordial feminine tension and satisfied with the surgery. Their personality, lifestyle, and self-esteem improved remarkably following surgery
    corecore