Wireless charging of mobile phones using microwaves ppt


Published on

Published in: Education
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Wireless charging of mobile phones using microwaves ppt

  1. 1. Wireless Charging of Mobile Phones Using Microwaves By, HARISH N NAYAK 8th SEM ECE
  3. 3. INTRODUCTION  Mobile phones becoming basic part of life  Recharging of mobile phones is a big problem  Objective—to recharge any mobile phone independent of manufacturer and battery make  Achieved by recharging battery while talking using microwaves Additives to mobile handsets: Sensor Rectenna
  4. 4. MICROWAVE REGION  Microwaves are the Radio wave which has the wave length range of 1 mm to 1 meter and the frequency is 300MHz to 300GHz.  Microwaves are good for transmitting information from one place to another  It is because microwave energy can penetrate rain and snow, clouds, and smoke  The frequency selection is another important aspect in transmission. Here we are going to use the S band of the Microwave Spectrum, which lies between 2-4GHz.We have selected the license free 2.45 GHz band for our purpose.
  5. 5. PRINCIPLE OF OPERATION Slotted waveguide Antenna mobile signal circulator sensor Transmitting station with the microwave transmitter RF cable Rectenna waveguide
  6. 6. OPERATION  Here as we can see there are two part. One is transmitting part and the other is the Receiving part  At the transmitting end there is one microwave power source which is actually producing microwaves The microwave signal is transmitted along with message signal using slotted wave guide antenna At the receiver side sensor search for the mobile signal , in addition it has a “RECTENNA”. Rectenna receives the transmitted power and converts the microwave power to DC power.
  7. 7. TRANSMITTER SECTION The transmitter section consists of two parts. They are:  Magnetron  Slotted waveguide antenna Magnetron
  8. 8. MAGNETRON Magnetron is a high power microwave oscillator and it is used in microwave oven and radar transmitter. Magnetron is the combination of a simple diode vacuum tube with built in cavity resonators and an extremely powerful permanent magnet. Magnetron is capable to deliver more power than reflex klystron or gunn diode Magnet is setup to affect the path of travel of electrons that are in transit from cathode to the anode plate.
  9. 9. THE SLOTTED WAVEGUIDE ANTENNA The slotted waveguide antenna consists of 8 waveguide sections with 8 slots on each section. These 64 slots radiate the power uniformly through free space to the rectenna. The slotted waveguide antenna is ideal for power transmission because of its high efficiency (> 95%) and high power handling capability. Slotted antenna arrays used with waveguides are popular antenna in navigation, radar and other high-frequency systems Has high efficiency and gain of 13dB Here we use frequency of 2.45GHz
  10. 10. RECEIVER SECTION RECTENNA The basic addition to the mobile phone is going to be the rectennas and sensor Rectenna = Rectifier + Antenna. A rectifying antenna called a rectenna receives the transmitted power and converts the microwave power to direct current (DC) power. Here antenna receives the microwave signal and diode rectifies the current induced in the antenna by the microwave This demonstration rectenna consists of 6 rows of dipoles antennas where 8 dipoles belong to each row. Each row is connected to a rectifying circuit which consists of low pass filters and a rectifier. The rectifier is a GaAs Schottky barrier diode that is impedance matched to the dipoles by a low pass filter.
  11. 11. SENSOR CIRCUITRY The sensor circuitry is a simple circuit, which detects if the mobile phone receives any message signal. This is required, as the phone has to be charged as long as the user is talking. Thus a simple F to V converter would serve our purpose.  In India the operating frequency of the mobile phone operators is generally 900MHz or 1800MHz for the GSM system for mobile communication. Thus the usage of simple F to V converters would act as switches to trigger the rectenna circuit to on.  A simple yet powerful F to V converter is LM2907.
  12. 12. ADVANTAGES The use of wired chargers are eliminated. The need of different types of chargers by different manufacturers is totally eliminated The phone can be charged at any place and any time. Only one microwave transmitter can serve to all the service providers in that area. The more we talk the more the phone get charged
  13. 13. DISADVANTAGES Wireless transmission of the energy causes some effects to human body, because of its radiation Network traffic may cause problems in charging Practical possibilities are not yet applicable as there is no much advancement in this field. Process is of high cost Charging depends on network coverage
  14. 14. CONCLUSION This paper successfully demonstrates a novel method of using the power of the microwave to charge the mobile phones without the use of wired chargers. Thus this method provides great advantage to the mobile phone users to carry their phones anywhere even if the place is devoid of facilities for charging. A novel use of the rectenna and a sensor in a mobile phone could provide a new dimension in the revelation of mobile phone.