757,333 research outputs found
Telemetry receiver
Communications system maintains phase lock of weak telemetry signals with a minimal expenditure of power and bandwidth. An estimate of the frequency variation as a function of time is used to achieve coherent phase demodulation
Digital receiver simulation
Digital simulation of the data link for the Saturn-Uranus spacecraft design is summarized. The data link is a 40 watt, 400 MegaHertz, 44 bit-a-second link, a power starved link, and uses convolution coding. Aspects of the link of particular interest are atmospheric scintillation and the Doppler to data rate ratio. The major characteristics of the scintillation are modeled in terms of tapped delay lines. A candidate system design and receiver design is developed. A computer flow diagram depicting a routine for the error rate and one for acquisition is presented. Various coding algorithms are analyzed since the convolution code is sensitive to the distribution of error and the actual pattern of the error
Tracking receiver Patent
Design and development of tracking receiver for tracking satellites and receiving radio signal transmissions under adverse noise condition
Optimal Energy Management for Energy Harvesting Transmitter and Receiver with Helper
We study energy harvesting (EH) transmitter and receiver, where the receiver
decodes data using the harvested energy from the nature and from an independent
EH node, named helper. Helper cooperates with the receiver by transferring its
harvested energy to the receiver over an orthogonal fading channel. We study an
offline optimal power management policy to maximize the reliable information
rate. The harvested energy in all three nodes are assumed to be known. We
consider four different scenarios; First, for the case that both transmitter
and the receiver have batteries, we show that the optimal policy is
transferring the helper harvested energy to the receiver, immediately. Next,
for the case of non-battery receiver and full power transmitter, we model a
virtual EH receiver with minimum energy constraint to achieve an optimal
policy. Then, we consider a non-battery EH receiver and EH transmitter with
battery. Finally, we derive optimal power management wherein neither the
transmitter nor the receiver have batteries. We propose three iterative
algorithms to compute optimal energy management policies. Numerical results are
presented to corroborate the advantage of employing the helper.Comment: It is a conference paper with 5 pages and one figure, submitted to
ISITA201
A (Simplified) Bluetooth Maximum a Posteriori Probability (Map) Receiver
In our software-defined radio project, we aim at combining two standards luetooth and HIPERLAN/2. The HIPERLAN/2 receiver requires more computational power than Bluetooth. We choose to use this computational power also for Bluetooth and look for more advanced demodulation algorithms such as a maximum a posteriori probability (MAP) receiver. The paper discusses a simplified MAP receiver for Bluetooth GFSK signals. Laurent decomposition provides an orthogonal vector space for the MAP receiver. As the first Laurent waveform contains the most energy, we have used only this waveform for our (simplified) MAP receiver. This receiver requires a E/sub b//N/sub 0/ of about 11 dB for a BER of 10/sup -3/, required by the Bluetooth standard. This value is about 6 dB better than single bit demodulators. This performance is only met if the receiver has exact knowledge of the modulation index
Solar thermal energy receiver
A plurality of heat pipes in a shell receive concentrated solar energy and transfer the energy to a heat activated system. To provide for even distribution of the energy despite uneven impingement of solar energy on the heat pipes, absence of solar energy at times, or failure of one or more of the heat pipes, energy storage means are disposed on the heat pipes which extend through a heat pipe thermal coupling means into the heat activated device. To enhance energy transfer to the heat activated device, the heat pipe coupling cavity means may be provided with extensions into the device. For use with a Stirling engine having passages for working gas, heat transfer members may be positioned to contact the gas and the heat pipes. The shell may be divided into sections by transverse walls. To prevent cavity working fluid from collecting in the extensions, a porous body is positioned in the cavity
Dynamic Sender-Receiver Games
We consider a dynamic version of sender-receiver games, where the sequence of
states follows an irreducible Markov chain observed by the sender. Under mild
assumptions, we provide a simple characterization of the limit set of
equilibrium payoffs, as players become very patient. Under these assumptions,
the limit set depends on the Markov chain only through its invariant measure.
The (limit) equilibrium payoffs are the feasible payoffs that satisfy an
individual rationality condition for the receiver, and an incentive
compatibility condition for the sender
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