WPT

To Nikola Tesla, probably more than to any other investigator belongs the greatest credit. In 1993 he publicly demonstrated wireless power before a meeting of the National Electric Light Association in St. Louis.In 1897 Nikola Tesla was the first to construct a vessel which could be controlled from a distance without connecting wires, a wireless controlled boat he called a "teleautomaton” which was demonstrated to the public during an electrical exhibition at Madison Square Garden. This automation was steered in obedience to guiding impulses of Hertzian waves sent out from shore. On Nov. 8, 1898, he was granted a United States patent for this invention. In this patent he mentions the use of all forms of control energy including electromagnetic induction, electrostatic induction, conduction through earth, water, and the upper atmosphere, and all forms of purely radiant energy.

The next major leap forward was Bill Brown’s rectenna helicopter in 1964 where he demonstrated a microwave powered helicopter that received all the power needed for flight from a ground based microwave beam, this may have been the first time that an aircraft did not carry an on board power source and flew solely from the power transmitted from the ground based transmitter!
Key to future applications of WPT (Wireless Power Transmission) or WiTricity as coined recently is the overall efficiency or ratio of power output to power input. In the 1969 to 1975 time period, Bill Brown managed a program that increased the overall efficiency, or ratio of DC power out to DC power in, to a JPL certified efficiency of 54%, several times greater than generally expected. He was also technical director of a JPL Raytheon program that beamed power over a distance of one mile to a rectenna which intercepted a portion of the beam and converted it to 30 kilowatts of DC power with 84% efficiency.
In a World first experiment on the 1stnd of December 2011, John R Iwaszko of AurumSolis Technologies in Melbourne Australia demonstrated a Free Flight of a Tesla Coil powered Flying Saucer! This experiment brings to life Tesla's dream of wireless powered flight, envisioned more than a century ago by Tesla.
By referring to Tesla’s Colorado spring notes, some of his receiver circuits utilise a low impedance resistance for a DC return path through a coherer and telegraph indicator which was the receiver’s electromechanical output transducer. Tesla used a battery but today a wirelessly charged and rectified super or Ultra capacitor can also allow the main or secondary capacitor to charge to a greater portion which has the same effect as an oscillator injected with negative resistance similar to “peak boost” which raises the effective Q and the important resonant rise of the voltage. The effective Q is then increased by a multiplicative factor, or Q multiplier. This narrows the selectivity curve and magnifies the circulating current, and has the same effect as making the detector stage regenerative, as with Armstrong’s super regenerative receiver patented in 1922. But Tesla’s sensitive detector is far simpler producing substantial gain from a simple circuit that only requires a few components, and works when adapted to wireless power transmission!
The device is basically a coanda style saucer shaped foam shroud with a helicopter within. The main receiving elements are combined to form a wireless resonant circuit. The receiving aerial is in the form of a ball, the oscillation capacitor that produce electrical oscillations and the main receiving loop coil is wrapped around the bottom hull of the saucer.
This small scale saucer shrouded helicopter flew solely by means of propulsive power from a ground base transmitter delivered by a Tesla Coil Transmitter with no onboard power supply or connection.

Due to the large number of paddle competitions held in Brazil each year, keep track of an athlete's results becomes an arduous task. The competitions results are often inaccessible in the long run, as paddle federations and confederations do not provide the scores already made by participants, which makes it difficult or even impossible for them to be able to make an analysis of their campaigns in competitions. This study proposed a mobile tool to centralize these results, in a practical and illustrated way, providing some statistical analysis of players activities. Finally, a tool quality analysis was carried out by the users, which proved the benefits brought to the sporting careers of the paddle players who use the application.

In today’s rapidly growing industries power source is a major aspect of any field. The use of wires is becoming redundant day by day. Considering this as a major issue, the fundamental idea here is to wipe out the utilisation of wires. This may be achieved by implementing wireless power transmission techniques which are far better than the standardised methods of transfer of power. Using close range and far range methods is dependent on the medium of its application.

In this paper, a novel orthogonal frequency division multiplexing (OFDM) system based on dual–tree complex wavelet transform (DT-CWT), is presented. In the proposed system, the DT-CWT is used to replace the fast Fourier transform (FFT) in the conventional OFDM. This results in considerable improvement in terms of bit error rate (BER) over not only the conventional OFDM but also to the wavelet packet modulation (WPM) based OFDM system. Moreover, the proposed system achieves better peak–to–average power ratio (PAPR) performance at acceptable increase in computational complexity. The complementary cumulative distribution function of PAPR for the proposed system shows ≈ 3 dB improvement over the conventional and the WPM based OFDM systems.

Digital speech signal is one of the most important types of data used due to the large number of computerized applications that are needed for mankind. Some computerized applications that use digital signals need a high level of security to protect the signal, and to turn it into a vague and incomprehensible signal to any third party, and that is why we have to seek a secure method of cryptography to protect the speech signal. In this research paper we will introduce a method based wavelet packet tree decomposition and reconstruction to generate an encrypted speech, the method will reorder the original speech using a secret number of decomposition levels, the obtained wavelet decomposition sizes will be used to form a speech segments, which must be rearranged in a secret order to get the encrypted speech, the introduced method will be implemented and evaluated to prove the security issues.