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Showing 1 to 14 of 14 for “"constant envelope"”.

  1. Stagger-tuned constant envelope-delay video I.F. amplifiers

    Lo, Arthur Wu-neinUniversity of Illinois at Urbana-Champaign1950

    uiuc Repository record

  2. Investigation into PRS-precoded, constant-envelope, continuous-phase digital modulation schemes

    Golby, John N ADepartment of Electrical Engineering1990

    … spectral performance and their maintenance of constant envelope.

    cape-town Repository record

  3. A low-cost digital matched filter for arbitrary constant envelope spread spectrum waveforms.

    Couturier, Normand J. A.Carleton University1985

    carleton Repository record

  4. Design and Implementation of a Constant Envelope OFDM Waveform in a Software-Defined Radio Platform

    Ajo, Amos V. Jr.Virginia Tech2016

    … answer to the PAPR-problem in the form of a constant-envelope OFDM (CE-OFDM) waveform, a waveform which employs phase modulation to transform the high-PAPR OFDM signal into a constant envelope signal, like FSK or GMSK, which can be amplified with non-linear power amplifiers at near saturation …

    vt Repository record

  5. Trellis Coded Modulation Schemes Using A New Expanded 16-Dimensional Constant Envelope Quadrature-Quadrature Phase Shift Keying Constellation

    Quinteros, Milton I.

    … author presents and analyzes two 4-dimensional Constant Envelope Quadrature-Quadrature Phase Shift Keying constellations. Optimal demodulators for the two constellations are presented, and one of them was designed and implemented by the author. In addition, a novel expanded 16-dimensional …

    uno Repository record

  6. Digital Transmission by Hermite N-Dimensional Antipodal Scheme

    Chongburee, WachiraVirginia Tech2004

    … N-dimensional Hermite transmission, outperforms constant envelope FSK in terms of spectrum efficiency. With a simple FM detector, the bit error rate of HK is as good as that of non-coherent FSK. In a frequency selective fading channel, the simulation results suggest that specific data bits of HK …

    vt Repository record

  7. Comparison of Machine Learning-Based Methods for Narrowband Blind Adaptive Beamforming

    Shonkwiler, LaraMassachusetts Institute of Technology2024

    … intrinsic characteristic of the signal, such as constant envelope properties or second or higher order statistics. Traditional blind source separation methods such as CMA, SOBI, JADE, and FastICA tend to be highly effective at beamforming datasets with moderate to large sample supports, but they …

    mit Repository record

  8. Efficiency Enhancement of Base Station Power Amplifiers Using Doherty Technique

    Viswanathan, VaniVirginia Tech2004

    … wireless applications such as WCDMA use non-constant envelope modulation techniques with a high peak to average ratio. Linearity being a critical issue, power amplifiers implemented in such applications are forced to operate at a backed off region from saturation. Therefore, in order to …

    vt Repository record

  9. Gallium nitride class-F power amplifier for UMTSWCDMA applications

    Khan, Farzana NoorUniversity of Ottawa (Canada)2013

    … be applied to UMTS/WCDMA since GSM uses the constant envelope feature of GMSK (Gaussian Minimum Shift Keying) modulation which introduces phase variations only. In UMTS, a WCDMA system with QPSK modulation is used where both phase and amplitude variations are introduced by the modulation. The …

    ottawa-retro Repository record

  10. Decoding algorithms for continuous phase modulation

    Kleyn, Werner FrederickDepartment of Electrical Engineering2002

    … amplifiers can be used in the transmitters of constant envelope CPM schemes. CPM also allows for the use of simple limiters in the demodulator rather than linear receivers with gain control. These characteristics not only increases the life of the power source, but it improves circuit …

    cape-town Repository record

  11. Time-dependence of ionization and excitation by intense, short electric pulses

    Dimitrovski, Darko

    … of the energy distribution to the relative envelope-carrier phase. In the strong field the periodic occurrence of ionization and recombination in time is termed "Rabi flopping involving the continuum" because after each odd half-cycle of the field the atom is practically 100% ionized and …

    freiburg-diss Repository record

  12. Multi-dimensional direct-sequence spread spectrum multiple-access communication with adaptive channel coding

    University of Pretoria2007

    … employs sophisticated double-sideband (DSB)Constant-Envelope Linearly Interpolated Root-of-Unity (CE-LI-RU) filtered General Chirp-Like (GCL) sequences [34, 37, 38] to band limit and spread user data. It then utilizes a fully user-definable, complex Multipath Fading Channel Simulator(MFCS), …

    pretoria Repository record

  13. Digital equalization techniques for the compensation of nonlinear impairments in long-haul coherent optical communication systems

    Βγενοπούλου, Βασιλική2018

    … due to its more compact spectrum and constant envelope compared to on-off keying. Nonetheless, fiber-optic communication systems using DPSK were severely degraded by nonlinear phase noise. One way to quantify this system degradation is to accurately derive the nonlinear phase noise …

    patras-thes Repository record

  14. Wide bandwidth high efficiency power converter for rf amplifiers

    Vasic, MiroslavIndustriales2010

    … asociadas con envolventes complejas (no constantes), ha alentado mucho esfuerzo de investigación en electrónica de potencia y comunicaciones hacia el desarrollo de técnicas de linealización que permitan el uso de amplificadores de alto rendimiento, inherentemente muy alinéales, con …

    upm Repository record