http://nopr.niscair.res.in/handle/123456789/9039 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/9050 Title: Realisation of high <i>Q</i> notch/allpass filter using low-voltage current conveyor <br/> <br/>Authors: Sharma, Susheel; Rana, Seema; Pal, K <br/> <br/>Abstract: A high quality factor (<i>Q</i>) biquad is realized using low-voltage (±0.75 V) second-generation current conveyors (CCII), which can realize dual filter functions (notch/allpass) depending on the resistance ratio. The circuit uses mostly grounded components, thus, enables its easy implementation in standard CMOS technologies. The circuit offers high input resistance (10²⁰ Ω) making it suitable for cascading and dissipates 3.8 mW power. The workability of this circuit has been<b> </b>verified by PSpice simulations using 0.5 mm technology parameters. <br/> <br/>Page(s): 435-437 http://nopr.niscair.res.in/handle/123456789/9049 Title: Effect of errors in position coordinates of the receiving antenna on single satellite GPS timing <br/> <br/>Authors: Sharma, Suman; Banerjee, P <br/> <br/>Abstract: <smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="country-region" downloadurl="http://www.5iantlavalamp.com/"><smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="place" downloadurl="http://www.5iantlavalamp.com/"><smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="City" downloadurl="http://www.5iamas-microsoft-com:office:smarttags"> It is well established that the position co-ordinates of the receiving antenna should be determined precisely in advance for getting time of the GPS receiver through a single GPS satellite technique. So it is desirable to know the extent of accuracy of the position coordinates required for a particular timing accuracy. In this paper, an analytical expression relating to the position error and the corresponding error in the time of the GPS receiver has been derived. Time of the GPS receiver error caused by the error in position coordinates largely depends on the position of the satellite indicated by the respective elevation and azimuth of the satellite. To validate the derived formulation, it is important to configure the experimental plan judiciously. A special experiment has accordingly been conducted at National Physical Laboratory, New Delhi, India (NPLI). The observed data have been found to tally well with the derived relation. </smarttagtype></smarttagtype></smarttagtype> <br/> <br/>Page(s): 429-434 http://nopr.niscair.res.in/handle/123456789/9048 Title: Electrical and optical properties of polyaniline polyvinyl alcohol composite films <br/> <br/>Authors: Bhadra, J; Sarkar, D <br/> <br/>Abstract: Polyaniline polyvinyl alcohol (PANI-PVA) composite films have been prepared chemically in inorganic acid medium at different ratios of their monomer units. A homogeneous blend can be obtained even using inorganic acid medium by terminating the reaction soon after the mixture attains homogeneous colour change. The SEM pictures show that the films have well formed grains with approximate sizes ranging from 0.3 to 1.2 <img src='/image/spc_char/micro.gif'> m. The results show definite dependence of various parameters on the PANI-PVA ratio in the blend.<b> </b>The XRD spectra show increase in crystallinity in the films with increase of PVA concentration. The FTIR spectra show some peaks, which ascertain chemical interlinking of PANI and PVA in these blends. The studies of electrical conductivity of these films through measurement of current-voltage (<i>I-V</i>) characteristics show non-ohmic power law behaviour (<i>I </i>a<i> V</i>ⁿ) with power (<i>n</i>) lying in the range 0.22 to 0.88. The conductivity value of these films is found to be between 1.80 to 0.9 S cm^-1. <br/> <br/>Page(s): 425-428 http://nopr.niscair.res.in/handle/123456789/9047 Title: Structural, electrical and optical behaviour of <i>rf</i> magnetron sputtered cuprous oxide films <br/> <br/>Authors: Reddy, M Hari Prasad; Reddy, P Narayana; Uthanna, S <br/> <br/>Abstract: Thin films of cuprous oxide have been deposited on glass substrates by sputtering of copper target at different substrate temperatures in the range 303-523 K and at oxygen partial pressure of 2×10^-2 Pa using <i>rf</i> magnetron sputtering method. The deposited films are characterised by studying crystallographic structure with X-ray diffraction, surface morphology by atomic force microscopy, and electrical and optical properties. The effect of substrate temperature on the physical properties of the deposited films has been systematically studied. The films deposited at 303 K are found amorphous while those formed at higher temperatures are polycrystalline with improved crystallinity. The electrical resistivity of the films decreases from 29 to 8 Ω cm and optical band gap increases from 2.15 to 2.32 eV with the increase of substrate temperature from 303 to 523 K. <br/> <br/>Page(s): 420-424