The Experts below are selected from a list of 5532 Experts worldwide ranked by ideXlab platform

Ernest M. Kim - One of the best experts on this subject based on the ideXlab platform.

  • A Short Study on the Validity of Miller's Theorem Applied to Transistor Amplifier High-Frequency Performance
    IEEE Transactions on Education, 2009
    Co-Authors: Thomas F. Schubert, Ernest M. Kim
    Abstract:

    The use of Miller's theorem in the determination of the high-frequency cutoff frequency of Transistor Amplifiers was recently challenged by a paper published in this transactions. Unfortunately, that paper provided no simulation or experimental results to bring credence to the challenge or to validate the alternate method of determination proposed. This paper provides SPICE simulation results that validate the common usage of Miller's theorem, limit the alternate method provided in that recent paper to a very small class of Amplifiers, and reinforce the need to consider Transistor Amplifiers as two-pole systems.

Marek E. Bialkowski - One of the best experts on this subject based on the ideXlab platform.

  • Transmit array of Transistor Amplifiers illuminated by a patch array in the reactive near-field region
    IEEE Transactions on Microwave Theory and Techniques, 2001
    Co-Authors: H.j. Song, Marek E. Bialkowski
    Abstract:

    In this paper, a small transmit array of Transistor Amplifiers illuminated by a passive array of microstrip patches in the reactive near-field region is investigated as a power-combining structure. The two cases considered are when the transmit array radiates in a free space and when a passive array similar to the one used for illumination collects the radiated power. A comparison of the performance of the proposed structure against the alternative one, which uses a conventional horn antenna as a power-launching/receiving device, is also presented.

  • Ku-band planar transmit-array module with Transistor Amplifiers
    Proceedings 2000 IEEE International Conference on Phased Array Systems and Technology (Cat. No.00TH8510), 1
    Co-Authors: Marek E. Bialkowski, H.j. Song
    Abstract:

    This paper presents the design, development and testing of a Ku-band planar transmit-array module of Transistor Amplifiers excited by either a pyramidal horn or a patch array. Investigations are performed into the power combining efficiency of these structures. After establishing optimal distances between the active transmit-array and the illuminating antenna, either the patch array or horn, the entire structure is tested in terms of gain, operational bandwidth and radiation pattern. The experimental results show that the use of a corporate-fed array as an illuminating device leads to a slightly higher gain and a significantly larger operational bandwidth.

A L Scholtz - One of the best experts on this subject based on the ideXlab platform.

  • design principles and limitations of integrated silicon bipolar Transistor Amplifiers for mobile communications
    Vehicular Technology Conference, 1993
    Co-Authors: N Rohringer, G Schultes, P Kreuzgruber, A L Scholtz
    Abstract:

    A numerical analysis of Class-C Amplifiers on the basis of a simple model of the bipolar junction Transistor is presented. The trade-off between collector efficiency, power added efficiency, gain, and input impedance of a 250-mW Class-C amplifier on one side and power supply voltage on the other is evaluated. Results are obtained using nonlinear time-domain simulation and optimization without recourse to graphical methods invoking the concept of conduction angle or to piecewise-linear approximations. It is found that, in contrast to other mobile terminal components, a reduction of the Class-C amplifier supply voltage causes lower gain and an increase of the required battery power at constant RF-output power.

P. K. Bhattacharya - One of the best experts on this subject based on the ideXlab platform.

H.j. Song - One of the best experts on this subject based on the ideXlab platform.

  • Transmit array of Transistor Amplifiers illuminated by a patch array in the reactive near-field region
    IEEE Transactions on Microwave Theory and Techniques, 2001
    Co-Authors: H.j. Song, Marek E. Bialkowski
    Abstract:

    In this paper, a small transmit array of Transistor Amplifiers illuminated by a passive array of microstrip patches in the reactive near-field region is investigated as a power-combining structure. The two cases considered are when the transmit array radiates in a free space and when a passive array similar to the one used for illumination collects the radiated power. A comparison of the performance of the proposed structure against the alternative one, which uses a conventional horn antenna as a power-launching/receiving device, is also presented.

  • Ku-band planar transmit-array module with Transistor Amplifiers
    Proceedings 2000 IEEE International Conference on Phased Array Systems and Technology (Cat. No.00TH8510), 1
    Co-Authors: Marek E. Bialkowski, H.j. Song
    Abstract:

    This paper presents the design, development and testing of a Ku-band planar transmit-array module of Transistor Amplifiers excited by either a pyramidal horn or a patch array. Investigations are performed into the power combining efficiency of these structures. After establishing optimal distances between the active transmit-array and the illuminating antenna, either the patch array or horn, the entire structure is tested in terms of gain, operational bandwidth and radiation pattern. The experimental results show that the use of a corporate-fed array as an illuminating device leads to a slightly higher gain and a significantly larger operational bandwidth.