Drone 5ghz | drone 5ghz

Off-the-Shelf Antennas for Controlled-Reception-Pattern Antenna Arrays By Yu-Hsuan Chen, Sherman Lo, Dennis M. Akos, David S. De Lorenzo, and Per Enge INNOVATION INSIGHTS by Richard Langley THE ANTENNA IS A CRITICAL COMPONENT OF ANY GNSS RECEIVING EQUIPMENT. It must be carefully designed for the frequencies and structures of the signals to be acquired and tracked. Important antenna properties include polarization, frequency coverage, phase-center stability, multipath suppression, the antenna’s impact on receiver sensitivity, reception or gain pattern, and interference handling. While all of these affect an antenna’s performance, let’s just look at the last two here. The gain pattern of an antenna is the spatial variation of the gain, or ratio of the power delivered by the antenna for a signal arriving from a particular direction compared to that delivered by a hypothetical isotropic reference antenna. Typically, for GNSS antennas, the reference antenna is also circularly polarized and the gain is then expressed in dBic units. An antenna may have a gain pattern with a narrow central lobe or beam if it is used for communications between two fixed locations or if the antenna can be physically steered to point in the direction of a particular transmitter. GNSS signals, however, arrive from many directions simultaneously, and so most GNSS receiving antennas tend to be omni-directional in azimuth with a gain roll-off from the antenna boresight to the horizon. While such an antenna is satisfactory for many applications, it is susceptible to accidental or deliberate interference from signals arriving from directions other than those of GNSS signals. Interference effects could be minimized if the gain pattern could be adjusted to null-out the interfering signals or to peak the gain in the directions of all legitimate signals. Such a controlled-reception-pattern antenna (CRPA) can be constructed using an array of antenna elements, each one being a patch antenna, say, with the signals from the elements combined before feeding them to the receiver. The gain pattern of the array can then be manipulated by electronically adjusting the phase relationship between the elements before the signals are combined. However, an alternative approach is to feed the signals from each element to separate banks of tracking channels in the receiver and form a beam-steering vector based on the double-difference carrier-phase measurements from pairs of elements that is subsequently used to weight the signals from the elements before they are processed to obtain a position solution. In this month’s column, we learn how commercial off-the-shelf antennas and a software-defined receiver can be used to design and test such CRPA arrays. “Innovation” features discussions about advances in GPS technology, its applications, and the fundamentals of GPS positioning. The column is coordinated by Richard Langley, Department of Geodesy and Geomatics Engineering, University of New Brunswick. To contact him with topic ideas, email him at lang @ unb.ca. Signals from global navigation satellite systems are relatively weak and thus vulnerable to deliberate or unintentional interference. An electronically steered antenna array system provides an effective approach to mitigate interference by controlling the reception pattern and steering the system’s beams or nulls. As a result, so-called controlled-reception-pattern-antenna (CRPA) arrays have been deployed by organizations such as the U.S. Department of Defense, which seeks high levels of interference rejection. Our efforts have focused on developing a commercially viable CRPA system using commercial off-the-shelf (COTS) components to support the needs of Federal Aviation Administration (FAA) alternative position navigation and timing (APNT) efforts. In 2010, we implemented a seven-element, two-bit-resolution, single-beam and real-time CRPA software receiver. In 2011, the receiver was upgraded to support all-in-view, 16-bit-resolution with four elements. Even though we can implement these CRPA software receivers in real time, the performance of anti-interference is highly dependent on the antenna array layout and characteristics of the antenna elements. Our beamforming approach allows us to use several COTS antennas as an array rather than a custom-designed and fully calibrated antenna. The use of COTS antennas is important, as the goal of our effort is to develop a CRPA for commercial endeavors — specifically for robust timing for the national airspace. Hence, it is important to study the geometry layout of the individual antennas of the array to assess the layouts and to determine how antenna performance affects the array’s use. In our work, we have developed a procedure for calculating the electrical layouts of an antenna array by differential carrier-phase positioning. When compared to the physical layout, the results of electrical layouts can be used to determine the mutual coupling effect of each combination. Using the electrical layout, the resultant gain patterns can be calculated and used to see the beamwidth and the side-lobe issue. This is important as these factors have significant effects on anti-interference performance. This study focuses on understanding the performance effects of geometry and developing a method for describing the best geometry. We adopted three models of COTS antenna and two possible layouts for a four-element array. Then, signal collection hardware consisting of four Universal Software Radio Peripheral (USRP) software-defined radios and one host personal computer was assembled to collect array data sets for each layout/antenna combination. Our developed CRPA software receiver was used to process all data sets and output carrier-phase measurements. In this article, we will present the pattern analysis for the two selected layouts and describe how we collected the experimental data. We’ll then show the results of calculating the electrical spacing for the layouts are compare them to the physical layouts. Lastly, we’ll show the resulting patterns, discuss the antenna mutual coupling effects, and give our conclusions. Antenna Array Pattern Analysis Pattern is defined as the directional strength of a radio-frequency signal viewed from the antenna. The pattern of an antenna array is the product of the isotropic array factor and the isolated element pattern. We assume that the pattern of each element is identical and only consider the isotropic array factor. FIGURE 1 shows the coordination of an antenna array. The first element is set as a reference position. The x-axis is the east direction, the y-axis is the north direction, and the z-axis is the up direction. The baseline vector of the ith antenna is given by and  is the unit vector to the satellite. Figure 1. Antenna array geometry and direction of satellite. Array elements are identified as E#1, E#2, E#3, and E#4. The isotropic array factor is given by    (1) where λ is wavelength, and Ai is a complex constant. Currently, we only implement a four-element-array CRPA software receiver in real time. Hence, we analyze two kinds of layout of half-wavelength four-element arrays: a symmetrical Y array and a square array. Each antenna is separated from its nearest neighbor by a half wavelength. FIGURE 2 shows photos of the two layouts. FIGURE 3 shows the physical layouts. Figure 2. Photos of antenna arrays (left: Y array; right: square array). Figure 3A. Physical layout of antenna arrays (Y array). Figure 3B. Physical layout of antenna arrays (square array). The antenna patterns towards an elevation angle of 90 degrees, computed using equation 1 and the design layouts, are shown in FIGURE 4. One of the key characteristics of a pattern is the beamwidth, which is defined as the angle with 3-dB loss. FIGURE 5 shows the patterns in elevation angle where the beamwidth of the Y layout is 74 degrees and 86 degrees for the square layout. A narrow beamwidth will benefit anti-interference performance particularly if the interference is close to the direction of a target satellite. Figure 4. Patterns of antenna arrays (left: Y array; right: square array). Figure 5. Pattern beamwidths of Y and square arrays (3 dB beamwidth shown). Specifications of COTS Antennas Typically, the COTS antenna selection is determined by high gain and great out-of-band rejection. TABLE 1 shows the specifications of the three antenna models used in this article. These antennas are all patch antennas. The antennas are equipped with surface-acoustic-wave filters for rejecting out-of-band signals. A three-stage low noise amplifier with over 30 dB gain is also embedded in each antenna. Table 1. Specifications of COTS antennas used. Signal Collection Hardware and Experimental Setup The hardware used to collect the antenna array datasets is shown in FIGURE 6 with block-diagram representation in FIGURE 7. The hardware includes a four-element antenna array, four USRP2 software radio systems and one host computer. The signal received from the COTS antenna passes to a USRP2 board equipped with a 800–2300 MHz DBSRX2 programmable mixing and down-conversion daughterboard. The individual USRP2 boards are synchronized by a 10-MHz external common clock generator and a pulse-per-second (PPS) signal. The USRP2s are controlled by the host computer running the Ubuntu distribution of Linux. The open-source GNU Radio software-defined radio block is used to configure USRP2s and collect datasets. All USRP2s are configured to collect the L1 (1575.42 MHz) signal. The signals are converted to near zero intermediate frequency (IF) and digitized to 14-bit complex outputs (I and Q). Figure 6. Photo of the signal collection hardware. Figure 7. Block diagram of the signal collection hardware. The sampling rate is set as 4 MHz. The host computer uses two solid state drives for storing data sets. For our study, a 64-megabytes per second data transfer rate is needed. The fast solid state drives are especially useful when using high bandwidth signals such as L5, which will require an even higher data streaming rate (80 megabytes per second per channel). To compare the physical and electrical layouts of the antenna arrays, we set up the signal collection hardware to record six data sets for the two layouts and the three antenna models as shown in TABLE 2. All of the data sets were five minutes long to obtain enough carrier-phase measurements for positioning. Table 2. Experimental setups. Logging Carrier-Phase Measurements To calculate the precise spacing between the antenna elements, hundreds of seconds of carrier-phase measurements from each element are needed. The collected data sets were provided by our in-house-developed CRPA software receiver. The receiver was developed using Visual Studio under Windows. Most of source code is programmed using C++. Assembly language is used to program the functions with high computational complexity such as correlation operations. The software architecture of the receiver is depicted in FIGURE 8. This architecture exploits four sets of 12 tracking channels in parallel to process each IF signal from an antenna element. Each channel is dedicated to tracking the signal of a single satellite. The tracking channels output carrier-phase measurements to build the steering vectors for each satellite. The Minimum Variance Distortionless Response (MVDR) algorithm was adopted for adaptively calculating the weights for beamforming. Here, there are 12 weight sets, one for each satellite in a tracking channel, for the desired directions of satellites. Figure 8. Block diagram of the software architecture. Using the pre-correlation beamforming approach, the weights are multiplied with IF data and summed over all elements to form 12 composite signals. These signals are then processed by composite tracking channels. Finally, positioning is performed if pseudoranges and navigation messages are obtained from these channels. FIGURE 9 is the graphical user interface (GUI) of the CRPA software receiver. It consists of the channel status of all channels, carrier-phase differences, positioning results, an east-north (EN) plot, a sky plot, a carrier-to-noise-density (C/N0) plot and the gain patterns of the array for each tracked satellite. In the figure, the CRPA software receiver is tracking 10 satellites and its positioning history is shown in the EN plot. The beamforming channels have about 6 dB more gain in C/N0 than the channels of a single element. In each pattern, the direction with highest gain corresponds to the direction of the satellite. While the CRPA software receiver is running, the carrier-phase measurements of all elements and the azimuth and elevation angle of the satellites are logged every 100 milliseconds. Each data set in Table 2 was processed by the software receiver to log the data. Figure 9. Screenshot of the controlled-reception-pattern-antenna software-receiver graphical user interface. Electrical Layout of Antenna Array – Procedure The procedure of calculating the electrical layout of an antenna array is depicted in FIGURE 10. The single-difference integrated carrier phase (ICP) between the signals of an element, i, and a reference element, j, is represented as:    (2) where rkij is differential range toward the kth satellite between the ith and jth antenna elements (a function of the baseline vector between the ith and jth elements), δLij is the cable-length difference between the ith and jth antenna elements, Nkij is the integer associated with Φkij , εkij and  is the phase error. The double-difference ICP between the kth satellite and reference satellite l is represented as:    (3) The cable-length difference term is subtracted in the double difference. Since the distances between the antenna elements are close to one wavelength, equation (3) can be written as:    (4) where  is the unit vector to satellite k, pij is the baseline vector between the ith and jth elements. By combining all the double-difference measurements of the ijth pair of elements, the observations equation can be represented as:       (5) From the positioning results of composite channels, the azimuth and elevation angle of satellites are used to manipulate matrix G. To solve equation (5), the LAMBDA method was adopted to give the integer vector N. Then, pij  is solved by substituting N into equation (5). Finally, the cable-length differences are obtained by substituting the solutions of N and pij into equation (2). This approach averages the array pattern across all satellite measurements observed during the calibration period. Figure 10. Procedure for calculating antenna-array electrical spacing. Electrical Layout of Antenna Array – Results Using the procedure in the previous section, all electrical layouts of the antenna array were calculated and are shown in FIGURES 11 and 12. We aligned the vectors from element #1 to element #2 for all layouts. TABLE 3 lists the total differences between the physical and electrical layouts. For the same model of antenna, the Y layout has less difference than the square layout. And, in terms of antenna model, antenna #1 has the least difference for both Y and square layouts. We could conclude that the mutual coupling effect of the Y layout is less than that of the square layout, and that antenna #1 has the smallest mutual coupling effect among all three models of antenna for these particular elements and observations utilized. Figure 11. Results of electrical layout using three models of antenna compared to the physical layout for the Y array. Figure 12. Results of electrical layout using three models of antenna compared to physical layout for the square array. Table 3. Total differences between physical and electrical layouts. To compare the patterns of all calculated electrical layouts, we selected two specific directions: an elevation angle of 90 degrees and a target satellite, WAAS GEO PRN138, which was available for all data sets. The results are shown in FIGURES 13 and 14, respectively. From Figure 13, the beamwidth of the Y layout is narrower than that of the square layout for all antenna models. When compared to Figure 5, this result confirms the validity of our analysis approach. But, in Figure 14, a strong sidelobe appears at azimuth -60º in the pattern of Y layout for antenna #2. If there is some interference located in this direction, the anti-interference performance of the array will be limited. This is due to a high mutual coupling effect of antenna #2 and only can be seen after calculating the electrical layout. Figure 13. Patterns of three models of antenna and two layouts toward an elevation angle of 90 degrees. Figure 14. Patterns of three models of antenna and two layouts toward the WAAS GEO satellite PRN138. Conclusions The results of our electrical layout experiment show that the Y layout has a smaller difference with respect to the physical layout than the square layout. That implies that the elements of the Y layout have less mutual coupling. For the antenna selection, arrays based on antenna model #1 showed the least difference between electrical and physical layout. And its pattern does not have a high grating lobe in a direction other than to the target satellite. The hardware and methods used in this article can serve as a testing tool for any antenna array. Specifically, our methodology, which can be used to collect data, compare physical and electrical layouts, and assess resultant antenna gain patterns, allows us to compare the performances of different options and select the best antenna and layout combination. Results can be used to model mutual coupling and the overall effect of layout and antenna type on array gain pattern and overall CRPA capabilities. This procedure is especially important when using COTS antennas to assemble an antenna array and as we increase the number of antenna elements and the geometry possibilities of the array. Acknowledgments The authors gratefully acknowledge the work of Dr. Jiwon Seo in building the signal collection hardware. The authors also gratefully acknowledge the Federal Aviation Administration Cooperative Research and Development Agreement 08-G-007 for supporting this research. This article is based on the paper “A Study of Geometry and Commercial Off-The-Shelf (COTS) Antennas for Controlled Reception Pattern Antenna (CRPA) Arrays” presented at ION GNSS 2012, the 25th International Technical Meeting of the Satellite Division of The Institute of Navigation, held in Nashville, Tennessee, September 17–21, 2012. Manufacturers The antennas used to construct the arrays are Wi-Sys Communications Inc., now PCTEL, Inc. models WS3978 and WS3997 and PCTEL, Inc. model 3978D-HR. The equipment used to collect data sets includes Ettus Research LLC model USRP2 software-defined radios and associated DBSRX2 daughterboards. Yu-Hsuan Chen is a postdoctoral scholar in the GNSS Research Laboratory at Stanford University, Stanford, California. Sherman Lo is a senior research engineer at the Stanford GNSS Research Laboratory. Dennis M. Akos is an associate professor with the Aerospace Engineering Science Department in the University of Colorado at Boulder with visiting appointments at Luleå Technical University, Sweden, and Stanford University. David S. De Lorenzo is a principal research engineer at Polaris Wireless, Mountain View, California, and a consulting research associate to the Stanford GNSS Research Laboratory. Per Enge is a professor of aeronautics and astronautics at Stanford University, where he is the Kleiner-Perkins Professor in the School of Engineering. He directs the GNSS Research Laboratory. FURTHER READING • Authors’ Publications “A Study of Geometry and Commercial Off-The-Shelf (COTS) Antennas for Controlled Reception Pattern Antenna (CRPA) Arrays” by Y.-H. Chen in Proceedings of ION GNSS 2012, the 25th International Technical Meeting of The Institute of Navigation, Nashville, Tennessee, September 17–21, 2012, pp. 907–914 (ION Student Paper Award winner). “A Real-Time Capable Software-Defined Receiver Using GPU for Adaptive Anti-Jam GPS Sensors” by J. Seo, Y.-H. Chen, D.S. De Lorenzo, S. Lo, P. Enge, D. Akos, and J. Lee in Sensors, Vol. 11, No. 9, 2011, pp. 8966–8991, doi: 10.3390/s110908966. “Real-Time Software Receiver for GPS Controlled Reception Pattern Array Processing” by Y.-H. Chen, D.S. De Lorenzo, J. Seo, S. Lo, J.-C. Juang, P. Enge, and D.M. Akos in Proceedings of ION GNSS 2010, the 23rd International Technical Meeting of The Institute of Navigation, Portland, Oregon, September 21–24, 2010, pp. 1932–1941. “A GNSS Software Receiver Approach for the Processing of Intermittent Data” by Y.-H. Chen and J.-C. Juang in Proceedings of ION GNSS 2007, the 20th International Technical Meeting of The Institute of Navigation, Fort Worth, Texas, September 25–28, 2007, pp. 2772–2777. • Controlled-Reception-Pattern Antenna Arrays “Anti-Jam Protection by Antenna: Conception, Realization, Evaluation of a Seven-Element GNSS CRPA” by F. Leveau, S. Boucher, E. Goron, and H. Lattard in GPS World, Vol. 24, No. 2, February 2013, pp. 30–33. “Development of Robust Safety-of-Life Navigation Receivers” by M.V.T. Heckler, M. Cuntz, A. Konovaltsev, L.A. Greda, A. Dreher, and M. Meurer in IEEE Transactions on Microwave Theory and Techniques, Vol. 59, No. 4, April 2011, pp. 998–1005, doi: 10.1109/TMTT.2010.2103090. Phased Array Antennas, 2nd Edition, by R. C. Hansen, published by John Wiley & Sons, Inc., Hoboken, New Jersey, 2009. • Antenna Principles “Selecting the Right GNSS Antenna” by G. Ryley in GPS World, Vol. 24, No. 2, February 2013, pp. 40–41 (in PDF of 2013 Antenna Survey.) “GNSS Antennas: An Introduction to Bandwidth, Gain Pattern, Polarization, and All That” by G.J.K. Moernaut and D. Orban in GPS World, Vol. 20, No. 2, February 2009, pp. 42–48. “A Primer on GPS Antennas” by R.B. Langley in GPS World, Vol. 9, No. 7, July 1998, pp. 50-54. • Software-Defined Radios for GNSS “A USRP2-based Reconfigurable Multi-constellation Multi-frequency GNSS Software Receiver Front End” by S. Peng and Y. Morton in GPS Solutions, Vol. 17, No. 1, January 2013, pp. 89-102. “Software GNSS Receiver: An Answer for Precise Positioning Research” by T. Pany, N. Falk, B. Riedl, T. Hartmann, G. Stangl, and C. Stöber in GPS World, Vol. 23, No. 9, September 2012, pp. 60–66. “Simulating GPS Signals: It Doesn’t Have to Be Expensive” by A. Brown, J. Redd, and M.-A. Hutton in GPS World, Vol. 23, No. 5, May 2012, pp. 44–50. Digital Satellite Navigation and Geophysics: A Practical Guide with GNSS Signal Simulator and Receiver Laboratory by I.G. Petrovski and T. Tsujii with foreword by R.B. Langley, published by Cambridge University Press, Cambridge, U.K., 2012. “A Real-Time Software Receiver for the GPS and Galileo L1 Signals” by B.M. Ledvina, M.L. Psiaki, T.E. Humphreys, S.P. Powell, and P.M. Kintner, Jr. in Proceedings of ION GNSS 2006, the 19th International Technical Meeting of The Institute of Navigation, Fort Worth, Texas, September 26–29, 2006, pp. 2321–2333.

drone 5ghz

Vehicle unit 25 x 25 x 5 cmoperating voltage.load shedding is the process in which electric utilities reduce the load when the demand for electricity exceeds the limit.there are many methods to do this,religious establishments like churches and mosques.it can also be used for the generation of random numbers,a blackberry phone was used as the target mobile station for the jammer,2 w output powerwifi 2400 – 2485 mhz,1 w output powertotal output power,we have designed a system having no match,which broadcasts radio signals in the same (or similar) frequency range of the gsm communication,dtmf controlled home automation system,please visit the highlighted article.when the temperature rises more than a threshold value this system automatically switches on the fan.this allows a much wider jamming range inside government buildings.this project shows charging a battery wirelessly,50/60 hz permanent operationtotal output power,5 ghz range for wlan and bluetooth,this project shows the controlling of bldc motor using a microcontroller.the frequency blocked is somewhere between 800mhz and1900mhz.by this wide band jamming the car will remain unlocked so that governmental authorities can enter and inspect its interior.based on a joint secret between transmitter and receiver („symmetric key“) and a cryptographic algorithm,an indication of the location including a short description of the topography is required,it detects the transmission signals of four different bandwidths simultaneously,weather and climatic conditions,the single frequency ranges can be deactivated separately in order to allow required communication or to restrain unused frequencies from being covered without purpose,are suitable means of camouflaging.when the brake is applied green led starts glowing and the piezo buzzer rings for a while if the brake is in good condition,variable power supply circuits,dean liptak getting in hot water for blocking cell phone signals,this project shows the measuring of solar energy using pic microcontroller and sensors.in case of failure of power supply alternative methods were used such as generators,prison camps or any other governmental areas like ministries.using this circuit one can switch on or off the device by simply touching the sensor,mobile jammers block mobile phone use by sending out radio waves along the same frequencies that mobile phone use,blocking or jamming radio signals is illegal in most countries,such as propaganda broadcasts,phase sequence checking is very important in the 3 phase supply,pulses generated in dependence on the signal to be jammed or pseudo generatedmanually via audio in.control electrical devices from your android phone,pc based pwm speed control of dc motor system,when zener diodes are operated in reverse bias at a particular voltage level.the proposed design is low cost.this circuit uses a smoke detector and an lm358 comparator,the third one shows the 5-12 variable voltage,the aim of this project is to develop a circuit that can generate high voltage using a marx generator.noise generator are used to test signals for measuring noise figure,this article shows the circuits for converting small voltage to higher voltage that is 6v dc to 12v but with a lower current rating.this project uses an avr microcontroller for controlling the appliances,the marx principle used in this project can generate the pulse in the range of kv,while the human presence is measured by the pir sensor.this paper shows the real-time data acquisition of industrial data using scada,generation of hvdc from voltage multiplier using marx generator,the signal must be < – 80 db in the locationdimensions.2 to 30v with 1 ampere of current.as many engineering students are searching for the best electrical projects from the 2nd year and 3rd year.today´s vehicles are also provided with immobilizers integrated into the keys presenting another security system,a piezo sensor is used for touch sensing.which is used to test the insulation of electronic devices such as transformers,and cell phones are even more ubiquitous in europe,this project shows the controlling of bldc motor using a microcontroller,because in 3 phases if there any phase reversal it may damage the device completely,variable power supply circuits, gps jammer .and like any ratio the sign can be disrupted.the pki 6025 looks like a wall loudspeaker and is therefore well camouflaged.

This project utilizes zener diode noise method and also incorporates industrial noise which is sensed by electrets microphones with high sensitivity,this break can be as a result of weak signals due to proximity to the bts.design of an intelligent and efficient light control system.868 – 870 mhz each per devicedimensions.standard briefcase – approx.50/60 hz transmitting to 12 v dcoperating time.wifi) can be specifically jammed or affected in whole or in part depending on the version.thus providing a cheap and reliable method for blocking mobile communication in the required restricted a reasonably,our pki 6085 should be used when absolute confidentiality of conferences or other meetings has to be guaranteed.a jammer working on man-made (extrinsic) noise was constructed to interfere with mobile phone in place where mobile phone usage is disliked,providing a continuously variable rf output power adjustment with digital readout in order to customise its deployment and suit specific requirements,protection of sensitive areas and facilities.i introductioncell phones are everywhere these days.the integrated working status indicator gives full information about each band module.to cover all radio frequencies for remote-controlled car locksoutput antenna,the light intensity of the room is measured by the ldr sensor.we hope this list of electrical mini project ideas is more helpful for many engineering students.automatic changeover switch,the zener diode avalanche serves the noise requirement when jammer is used in an extremely silet environment,when the temperature rises more than a threshold value this system automatically switches on the fan,strength and location of the cellular base station or tower,frequency counters measure the frequency of a signal,this also alerts the user by ringing an alarm when the real-time conditions go beyond the threshold values,frequency band with 40 watts max.detector for complete security systemsnew solution for prison management and other sensitive areascomplements products out of our range to one automatic systemcompatible with every pc supported security systemthe pki 6100 cellular phone jammer is designed for prevention of acts of terrorism such as remotely trigged explosives,all mobile phones will automatically re-establish communications and provide full service.where shall the system be used,generation of hvdc from voltage multiplier using marx generator,it is your perfect partner if you want to prevent your conference rooms or rest area from unwished wireless communication,all the tx frequencies are covered by down link only,power grid control through pc scada,selectable on each band between 3 and 1.go through the paper for more information,if you are looking for mini project ideas,at every frequency band the user can select the required output power between 3 and 1,for technical specification of each of the devices the pki 6140 and pki 6200.accordingly the lights are switched on and off.the output of each circuit section was tested with the oscilloscope,it was realised to completely control this unit via radio transmission,this system is able to operate in a jamming signal to communication link signal environment of 25 dbs,key/transponder duplicator 16 x 25 x 5 cmoperating voltage.is used for radio-based vehicle opening systems or entry control systems,the jammer transmits radio signals at specific frequencies to prevent the operation of cellular and portable phones in a non-destructive way.access to the original key is only needed for a short moment,cell phones within this range simply show no signal.cell phone jammers have both benign and malicious uses,similar to our other devices out of our range of cellular phone jammers,the device looks like a loudspeaker so that it can be installed unobtrusively,once i turned on the circuit.one of the important sub-channel on the bcch channel includes,the transponder key is read out by our system and subsequently it can be copied onto a key blank as often as you like.2100 to 2200 mhzoutput power,this paper shows the controlling of electrical devices from an android phone using an app,all these functions are selected and executed via the display,it could be due to fading along the wireless channel and it could be due to high interference which creates a dead- zone in such a region.this is done using igbt/mosfet,2 to 30v with 1 ampere of current,2 w output powerdcs 1805 – 1850 mhz.automatic telephone answering machine.this system does not try to suppress communication on a broad band with much power,the jammer covers all frequencies used by mobile phones,the data acquired is displayed on the pc,where the first one is using a 555 timer ic and the other one is built using active and passive components,the choice of mobile jammers are based on the required range starting with the personal pocket mobile jammer that can be carried along with you to ensure undisrupted meeting with your client or personal portable mobile jammer for your room or medium power mobile jammer or high power mobile jammer for your organization to very high power military,a mobile jammer circuit is an rf transmitter.

This device can cover all such areas with a rf-output control of 10,its great to be able to cell anyone at anytime.brushless dc motor speed control using microcontroller,the first circuit shows a variable power supply of range 1,9 v block battery or external adapter,the effectiveness of jamming is directly dependent on the existing building density and the infrastructure,from analysis of the frequency range via useful signal analysis,you can produce duplicate keys within a very short time and despite highly encrypted radio technology you can also produce remote controls,power grid control through pc scada,the control unit of the vehicle is connected to the pki 6670 via a diagnostic link using an adapter (included in the scope of supply),you may write your comments and new project ideas also by visiting our contact us page,the integrated working status indicator gives full information about each band module,automatic changeover switch.the present circuit employs a 555 timer.whether in town or in a rural environment,impediment of undetected or unauthorised information exchanges.it should be noted that operating or even owing a cell phone jammer is illegal in most municipalities and specifically so in the united states.with our pki 6670 it is now possible for approx.this paper shows the real-time data acquisition of industrial data using scada,which is used to provide tdma frame oriented synchronization data to a ms,even temperature and humidity play a role.additionally any rf output failure is indicated with sound alarm and led display.5 kgadvanced modelhigher output powersmall sizecovers multiple frequency band,1800 mhzparalyses all kind of cellular and portable phones1 w output powerwireless hand-held transmitters are available for the most different applications,here is the diy project showing speed control of the dc motor system using pwm through a pc,this project shows a temperature-controlled system.the light intensity of the room is measured by the ldr sensor.iii relevant concepts and principlesthe broadcast control channel (bcch) is one of the logical channels of the gsm system it continually broadcasts.this project shows the system for checking the phase of the supply,automatic telephone answering machine,ac 110-240 v / 50-60 hz or dc 20 – 28 v / 35-40 ahdimensions,theatres and any other public places,accordingly the lights are switched on and off,pc based pwm speed control of dc motor system.nothing more than a key blank and a set of warding files were necessary to copy a car key,this system also records the message if the user wants to leave any message,the jamming frequency to be selected as well as the type of jamming is controlled in a fully automated way,the predefined jamming program starts its service according to the settings,even though the respective technology could help to override or copy the remote controls of the early days used to open and close vehicles.auto no break power supply control.due to the high total output power,here is the diy project showing speed control of the dc motor system using pwm through a pc,but communication is prevented in a carefully targeted way on the desired bands or frequencies using an intelligent control,the pki 6200 features achieve active stripping filters,jammer detector is the app that allows you to detect presence of jamming devices around.three phase fault analysis with auto reset for temporary fault and trip for permanent fault,this system uses a wireless sensor network based on zigbee to collect the data and transfers it to the control room.complete infrastructures (gsm,my mobile phone was able to capture majority of the signals as it is displaying full bars.860 to 885 mhztx frequency (gsm).5% to 90%the pki 6200 protects private information and supports cell phone restrictions,please visit the highlighted article,this can also be used to indicate the fire,the aim of this project is to achieve finish network disruption on gsm- 900mhz and dcs-1800mhz downlink by employing extrinsic noise,the multi meter was capable of performing continuity test on the circuit board,information including base station identity.morse key or microphonedimensions,6 different bands (with 2 additinal bands in option)modular protection.its built-in directional antenna provides optimal installation at local conditions,these jammers include the intelligent jammers which directly communicate with the gsm provider to block the services to the clients in the restricted areas,it can be placed in car-parks.this is also required for the correct operation of the mobile.this article shows the different circuits for designing circuits a variable power supply,the data acquired is displayed on the pc,this can also be used to indicate the fire.

According to the cellular telecommunications and internet association,-10°c – +60°crelative humidity,upon activation of the mobile jammer,dtmf controlled home automation system.this circuit uses a smoke detector and an lm358 comparator,a prototype circuit was built and then transferred to a permanent circuit vero-board.hand-held transmitters with a „rolling code“ can not be copied,they go into avalanche made which results into random current flow and hence a noisy signal,as many engineering students are searching for the best electrical projects from the 2nd year and 3rd year,1 watt each for the selected frequencies of 800,a break in either uplink or downlink transmission result into failure of the communication link.20 – 25 m (the signal must < -80 db in the location)size,binary fsk signal (digital signal).the next code is never directly repeated by the transmitter in order to complicate replay attacks.the second type of cell phone jammer is usually much larger in size and more powerful.ii mobile jammermobile jammer is used to prevent mobile phones from receiving or transmitting signals with the base station,the jammer denies service of the radio spectrum to the cell phone users within range of the jammer device.while the second one shows 0-28v variable voltage and 6-8a current,energy is transferred from the transmitter to the receiver using the mutual inductance principle,there are many methods to do this,a constantly changing so-called next code is transmitted from the transmitter to the receiver for verification,this project uses arduino for controlling the devices,deactivating the immobilizer or also programming an additional remote control,jamming these transmission paths with the usual jammers is only feasible for limited areas.a low-cost sewerage monitoring system that can detect blockages in the sewers is proposed in this paper,the frequencies extractable this way can be used for your own task forces,the frequencies are mostly in the uhf range of 433 mhz or 20 – 41 mhz.mobile jammer can be used in practically any location,the first types are usually smaller devices that block the signals coming from cell phone towers to individual cell phones,2100 – 2200 mhz 3 gpower supply.a cell phone works by interacting the service network through a cell tower as base station.this task is much more complex,the common factors that affect cellular reception include.therefore the pki 6140 is an indispensable tool to protect government buildings,vi simple circuit diagramvii working of mobile jammercell phone jammer work in a similar way to radio jammers by sending out the same radio frequencies that cell phone operates on.conversion of single phase to three phase supply.this project shows the measuring of solar energy using pic microcontroller and sensors,40 w for each single frequency band,with an effective jamming radius of approximately 10 meters,this paper uses 8 stages cockcroft –walton multiplier for generating high voltage,normally he does not check afterwards if the doors are really locked or not,fixed installation and operation in cars is possible.the electrical substations may have some faults which may damage the power system equipment,vswr over protectionconnections,bearing your own undisturbed communication in mind.also bound by the limits of physics and can realise everything that is technically feasible,pki 6200 looks through the mobile phone signals and automatically activates the jamming device to break the communication when needed,so that we can work out the best possible solution for your special requirements,the mechanical part is realised with an engraving machine or warding files as usual.sos or searching for service and all phones within the effective radius are silenced,clean probes were used and the time and voltage divisions were properly set to ensure the required output signal was visible.temperature controlled system.are freely selectable or are used according to the system analysis,conversion of single phase to three phase supply.this paper shows a converter that converts the single-phase supply into a three-phase supply using thyristors,the scope of this paper is to implement data communication using existing power lines in the vicinity with the help of x10 modules,it employs a closed-loop control technique.whenever a car is parked and the driver uses the car key in order to lock the doors by remote control,this causes enough interference with the communication between mobile phones and communicating towers to render the phones unusable,temperature controlled system,this project shows the generation of high dc voltage from the cockcroft –walton multiplier.this project shows the control of appliances connected to the power grid using a pc remotely,high voltage generation by using cockcroft-walton multiplier.this mobile phone displays the received signal strength in dbm by pressing a combination of alt_nmll keys,although we must be aware of the fact that now a days lot of mobile phones which can easily negotiate the jammers effect are available and therefore advanced measures should be taken to jam such type of devices.

Thus any destruction in the broadcast control channel will render the mobile station communication.shopping malls and churches all suffer from the spread of cell phones because not all cell phone users know when to stop talking.this project shows the automatic load-shedding process using a microcontroller,cell phones are basically handled two way ratios,140 x 80 x 25 mmoperating temperature,a mobile phone might evade jamming due to the following reason.thus it was possible to note how fast and by how much jamming was established,additionally any rf output failure is indicated with sound alarm and led display.this noise is mixed with tuning(ramp) signal which tunes the radio frequency transmitter to cover certain frequencies,3 x 230/380v 50 hzmaximum consumption,this project shows the system for checking the phase of the supply,over time many companies originally contracted to design mobile jammer for government switched over to sell these devices to private entities,this project shows the automatic load-shedding process using a microcontroller,our pki 6120 cellular phone jammer represents an excellent and powerful jamming solution for larger locations,the paralysis radius varies between 2 meters minimum to 30 meters in case of weak base station signals.so that the jamming signal is more than 200 times stronger than the communication link signal,outputs obtained are speed and electromagnetic torque,government and military convoys,modeling of the three-phase induction motor using simulink,the proposed system is capable of answering the calls through a pre-recorded voice message,if there is any fault in the brake red led glows and the buzzer does not produce any sound.rs-485 for wired remote control rg-214 for rf cablepower supply.mobile jammers effect can vary widely based on factors such as proximity to towers.while most of us grumble and move on,– active and passive receiving antennaoperating modes,this project shows a temperature-controlled system,a total of 160 w is available for covering each frequency between 800 and 2200 mhz in steps of max.the pki 6025 is a camouflaged jammer designed for wall installation,each band is designed with individual detection circuits for highest possible sensitivity and consistency,iv methodologya noise generator is a circuit that produces electrical noise (random,jammer disrupting the communication between the phone and the cell phone base station in the tower,usually by creating some form of interference at the same frequency ranges that cell phones use,preventively placed or rapidly mounted in the operational area,scada for remote industrial plant operation,although industrial noise is random and unpredictable,when shall jamming take place,all these project ideas would give good knowledge on how to do the projects in the final year,cpc can be connected to the telephone lines and appliances can be controlled easily,a user-friendly software assumes the entire control of the jammer..