Airborne lidar/INS/GNSS: Algorithm Uses Fuzzy Controlled Scale Invariant Feature Transform Sensor role reversal: Lidar with its superior performance can replace GNSS in the integration solution by providing fixes for the drifting inertial measurement unit (IMU). Tests show its potential for terrain-referenced navigation due to its high accuracy, resolution, update rate and anti-jamming abilities. A novel algorithm uses scanning lidar ranging data and a reference database to calculate the navigation solution of the platform and then further fuse with the inertial navigation system (INS) output data. Recent rapid advances in laser-based remote sensing technologies, including pulsed linear, array and flash lidar systems, have fostered the development of integrated navigation algorithms for lidar and inertial sensors. In particular, trajectory recovery based on lidar point-cloud matching can provide valuable input to the navigation filter. Lidar/INS integrated navigation systems may provide continuous and fairly accurate navigation solutions in GNSS-challenged environments, on a variety of platforms, such as unmanned ground vehicles, mobile robot navigation and autonomous driving. In the case of airborne lidar/INS applications, the free inertial navigation solution is used to create the point clouds, which are subsequently matched to a digital terrain elevation model (DEM). The results are fed back to the platform navigation filter, providing corrections to the free navigation solution. This solution may be used to recreate the point cloud to obtain better surface data. However, depending on the lidar data acquisition parameters, INS drift during the time between the two epochs when point clouds are acquired could be significant. Besides the shift in platform position, the drift in attitude angles could more severely impact point-cloud generation, producing a less accurate point cloud and subsequently poor matching performance. This article describes a new lidar positioning approach, where the scale-invariant feature transform (SIFT)-based lidar positioning algorithm is used to match between the lidar measured point cloud and the reference DEM. The matching process is aided with fuzzy control: SIFT-based lidar positioning algorithm with Fuzzy logic (SLPF), where the threshold for SIFT is adaptively controlled by the fuzzy logic system. Based on the geometric distribution and the range difference variance of the matched point clouds, fuzzy logic is applied to calculate the threshold for the SIFT algorithm to extract feature points; thus the optimal matched point cloud is extracted in several iterations. When there are enough matched points in the final output of the SLPF, the platform position is calculated by using the least squares method (LSM). Next, for trajectory estimation, when applying the SLPF algorithm, frequent lidar updates can be used to correct small cumulative errors from the INS sensor measurements. A Kalman filter fuses the results of the SLPF algorithm with the INS system. This integrated algorithm can handle situations when there are less than three matched feature points being extracted by the SLPF algorithm, and yet they could still contribute to obtain a better navigation solution. Simulation results show that, compared to the existing algorithms, the proposed lidar/INS integrated navigation algorithm not only improves the position, speed and attitude-determination accuracy, it also makes the lidar less dependent on INS, which makes the navigation system work longer without exceeding a particular drift threshold. LIDAR ALGORITHM To eliminate the influence of INS error on the lidar positioning system, instead of creating a measured DEM based on INS ortho-rectification, we directly map the range data measured by lidar to the local stored DEM data. If a successfully matched feature point can be obtained, it means that we can get a point with absolute position and relative range towards the platform, which is similar to the satellite in GNSS positioning. After scanning of one area by lidar, when three or more such matched feature points, if not on a line, can be obtained, then we are able to form a full rank equation with the unknown variables of the platform position x, y and z. However, due to the effect of affine transformation, the standardized range dataset collected by lidar is significantly different from the elevation dataset belonging to the same area. Figure 1 shows an example of the large difference between the two datasets from the same area when the pitch angle of the platform is equal to 5° and the flying height is 2,000 m. In this situation, the traditional flooding algorithm or constellation feature point matching algorithm is incapable of extracting matched feature points from such different datasets. Figure 1. Comparison between SR and DEM data from the same area. In response, we introduce the SIFT algorithm to the elevation map-matching procedure. Designed for image matching, the SIFT algorithm is invariant to scale, rotation and translation, and it is robust to affine transformation and three-dimensional projection transformation to a certain extent. Although SIFT is often used in image matching, each pixel from the image is a numerical point, which, in fact, has no difference with elevation data point. Before applying the SIFT, some processing on the lidar measured range data must be done. LIDAR RANGE DATA The scanning information of the lidar measured points are (α, β, r), where α is the angle between the laser beam and the negative Z-axis of the platform body frame, β is the angle from the laser beam to the plane of axis and Z-axis in body frame, r is the range between the laser head and the measured target, as shown in the opening figure. Due to the terrain relief, the lidar range data are irregularly spaced. Therefore, it is necessary to interpolate the collected data. Here we apply the Natural Neighbor Interpolation method. SIFT Algorithm, Fuzzy Control. For the lidar positioning algorithm, which is based on the absolute position and relative range of the ground-matched feature points, a point cloud with sufficient number of points of good geometric distribution is needed. In practice, however, the terrain undulation and the attitude of the airplane will affect the quality of the point cloud and the accuracy in the matching process. In addition, the selected threshold in the SIFT algorithm plays an important role on the quality of the matched point cloud. A Monte Carlo simulation, shown in FIGURE 2, illustrates the impact of the threshold on the number of successful matched points (normalized) and mismatched rate. For obtaining better matched point clouds, we have introduced a SIFT terrain matching algorithm assisted by fuzzy control, as shown in FIGURE 3. Figure 2. Relationship effect of threshold on the number of successful matched point (normalized) and error matched rate. Figure 3. Working principal diagram of SIFT terrain matching algorithm based on fuzzy control. The algorithm mainly consists of two fuzzy logic controllers. Controller 1 calculates the initial threshold for the SIFT algorithm according to the gridded SR data terrain undulation degree λ, and the angle Θ between Z-axis in body-frame and Z-axis in navigation frame. Controller 2, which is responsible to adaptively changing the threshold at each epoch, has two inputs. The first one is the Normalized Points Area (NPA), which represent the geometric condition of the matched point cloud. The other one is the Relative Range Difference Variance, which indicates if a mismatch has happened. When the final matched feature point cloud is obtained, and the number of points is greater than or equal to 3, then the LSM is used to calculate the position of the platform. INS/LIDAR NAVIGATION Loosely and tightly coupled integration are the most common methods in navigation systems. Given the characteristics of the proposed positioning algorithm, the classical integrated navigation algorithm needs to be modified. In the loosely coupled approach, the lidar is unable to aid INS when flying through a flat region and/or flying with a large tilt angle, because the proposed lidar positioning method may have difficulty in extracting enough matched points to calculate a position. In the tightly coupled method, as the output frequency of matched point cloud is low and the geometry of the matched feature points is relatively poor, the integrated system may be extremely unstable. Here we propose a combined loosely and tightly (CLT) integrated navigation algorithm that when the lidar positioning algorithm can extract enough matched points for a navigation solution, the lidar-calculated navigation solution is used as the main observation. However, when the matched points are not sufficient to obtain a navigation solution, the baseline vector of the matched point that is closer to the projection of the platform center to the surface will be utilized as the observation. In this solution, lidar can still provide a certain degree of aid to the INS, once extracting matched feature points, even if less than 3. SIMULATION ANALYSIS In the simulation experiment, the 3D DEM data of 0.5-meter resolution is obtained from an open source named EOWEB. Then the DEM data is resampled to a higher resolution of 0.1 meter, which is used to generate the simulated, irregularly spaced, measured range data. On the basis of the original DEM (0.5 meter resolution), the proposed lidar positioning algorithm and lidar/INS integrated navigation algorithm are verified and compared with the traditional methods. Simulation of Lidar Algorithm. As shown above, the successfully matched points rate is very important for positioning, as once a mismatched point occurs, it may lead to a faulty navigation solution. In the simulation, the proposed SLPF is simulated under the condition of different aircraft tilt angle ϴ, from 0° to 10° with a step of 1° , at 5,000 different positions, which is the same simulation condition as in Figure 2. Comparison is made with the traditional constellation feature matching based lidar positioning algorithm (CLP) and the SIFT based lidar positioning algorithm without fuzzy control (SLP). The successfully matched points rate and the NPA value are shown in Figure 4. Figure 4. Successful points matched rate and the NPA value results under different aircraft attitude condition from three different algorithms. As can be seen from the figure, along with the increasing platform attitude angle, the successfully matched points rate of all the three algorithms has declined. However, compared to the CLP, both SIFT-based algorithms have a higher success matching rate due to the more stringent feature-point extraction approach. And due to the adjustable threshold mechanism, the SLPF could remove some of the mismatched points by raising the threshold; thus it is superior to the common SIFT algorithm in performance. The NPA values of the extracted point cloud from the three algorithms are shown in Figure 4(b). With the increased attitude angle, the NPA value of the matching feature point cloud decreases in all three algorithms. The CLP algorithm, however, is more sensitive to the projected range data, which makes the number of successful matching points drop sharply, and further affect geometric distribution of the point cloud. The gap between the SLPF and SLP shows that the fuzzy control module can help improve the geometric structure of the feature point cloud. Figure 5 shows the positioning error when applying the three different matching algorithms at 5,000 different areas. The SLPF algorithm is better than the other two algorithms in all directions. When the platform’s attitude angle reaches about 10 degrees, the north and east positioning accuracy of SLPF algorithm is still about 8 meters, and the height positioning accuracy is about 0.2 meters. The reason that the height positioning error is far less than the north and east positioning error is because of the matching point cloud distribution. Due to the airborne lidar scanning mechanism, the matched point cloud is all located in a relative small area at the bottom of the platform, resulting in the great component value in the height direction of each matched feature point baseline vector in the G matrix, and then affect the final positioning accuracy. Figure 5. Positioning accuracy under different aircraft attitude conditions with different algorithms. Table 1 shows some detailed information as average number of matched points (ANMP) and matched points position error (MPPE) using the three methods. The MPPE is calculated in 3D space. It can be seen that when the tilt attitude is small, comparing to the CLP method, although the number of matched points extracted by SLPF is less, the matched points position accuracy is still much better, leading to a better localization result. Moreover, with the increasing platform tilt attitude, CLP and SLP have more difficulty in maintaining the number and accuracy of the matched points. Lidar/INS Algorithm. To validate the feasibility of the proposed integrated navigation algorithm, firstly, the motion trajectory of the platform must be simulated. As shown in Figure 6, the red line is the simulated platform true trajectory, which lasts for 1,400 seconds. During the trajectory, the platform undertakes the different motion states as acceleration, deceleration, climbing, turning and descent. Then the INS output data based on the true trajectory with the frequency of 100 Hz is generated. To verify the calibration performance on the INS in the integrated navigation algorithm, accelerometer and gyroscope drift noise is added to the INS output data. The green line shown in Figure 6 is the INS output data trajectory solution. At the end of simulation, the error to the east direction reaches 500 meters, and the north direction error reaches to more than 2,200 meters. Figure 6. Comparison between True trajectory and INS calculated trajectory. At the same time of the INS outputting navigation solution, lidar also scans and calculates the position of the platform with 1-Hz frequency. Note that the speed of the aircraft is from 70 m/s to 100 m/s, and the maximum lidar scanning angle αmax is 20°. Figure 7 and Figure 8 show the number of matched points and the positioning error for each scanned terrain using SLFP. When the platform maintains smooth flying, the number of matched points can reach an average of 10, and the positioning accuracy is relatively high, less than 3 meters. Note, during the period, only in a few epochs are the number of matched points less than five. However, when the platform is climbing or changing flight direction, the number of matched points is obviously decreased due to the large tilt angle of the platform, and so does the number of successful positioning times. In this case, the position error is also increased dramatically, reaching about 10 meters error in east and north, and 0.2 meters error in height. Especially in the course of changing the direction of the flight, shown in Figure 7, during the periods of 720s–800s and 920s–1,000s, due to the larger roll angle, the SLPF could hardly be able to calculate the position through the LSM. During this period the lidar would occasionally output 1 or 2 matched feature points. Figure 7. The number of the matched points of each lidar positioning epoch. Figure 8. The positioning accuracy of each lidar positioning epoch. During the simulation, the CLT and LC methods are used for data fusion and trajectory estimation comparisons. TC method is not added to the comparison because of slow convergence. The data fusion results are shown in Figure 9. It illustrates that the LC method and the CLT method have close positioning accuracy in the case of sufficient matched feature points. As can be seen in conjunction with Figure 8, when lacking matched points, the CLT method is superior to LC on positioning accuracy, especially in the height direction. In addition, the CLT integrated algorithm shows some improvement on the accuracy of estimating speed and attitude. Figure 9a. Data fusion results using two different integrated algorithms: position determination error. Figure 9b. Data fusion results using two different integrated algorithms:velocity determination error. Figure 9c. Data fusion results using two different integrated algorithms: attitude determination error. Figure 10 shows the position error distribution when using four different lidar/INS integrated navigation methods for data fusion under the condition of different simulation trajectories. In the simulation, 50 1,400-second-long different trajectories, with flat areas, are generated with different platform attitude, velocity or acceleration. As can be seen from the figure, compared to other integrated navigation methods, the CLT method greatly improves the accuracy of navigation. Figure 10. Position error distribution when using four differentlidar/INS integrated navigation method. During 84.26% of the simulation period, CLT could maintain the position error less than 3 meters; the rate with error that is larger than 15 meters is 1.2%. For the TC method, due to the frequent divergence of the data fusion filter, most of the position estimates are not available. In addition, after flying above a flat area, the voting-based constellation integrated method has poor matched point accuracy and successfully matched rate due to large INS drift error, which makes lidar unable to calibrate the INS. When using the constellation-based method, during only 32.35% of the simulation period, the error is maintained in 3 meters and most of the period, 54.9%, the position error is between 3 to 15 meters. CONCLUSION We propose a new lidar matching algorithm based on SIFT, which does not rely on the INS output data to generate measured DEM data, and can adaptively change the threshold of the SIFT algorithm to generate optimal matching between the point cloud and the DEM. Through verification of simulation, the algorithm is compared with traditional lidar/INS integrated navigation methods based on comparing achieved accuracies in estimating position, speed and attitude. Simulation results show that the SLPF algorithm has better reliability for feature points matching and robustness against the platform attitude than the traditional algorithms. The CLT method improves trajectory estimation accuracy, especially when flying over moderately undulating terrain or flying with large roll or pitch angles. ACKNOWLEDGMENT This article is based on a paper presented at the ION International Technical Meeting, January 2017. This research used an open-source GNSS/INS simulator based on Matlab, developed by Gongmin Yan of Northwestern Polytechnical University, China. Haowei Xu is a Ph.D. student at Northwestern Polytechnical University, where he received an M.Sc in Information and Communication Engineering. He is a visiting scholar at The Ohio State University. Baowang Lian is a professor at Northwestern Polytechnical University where he is also director of the Texas Instruments DSPs Laboratory. Charles K. Toth is a senior research scientist at the Ohio State University Center for Mapping. He received a Ph.D. in electrical engineering and geo-information sciences from the Technical University of Budapest, Hungary. Dorota A. Brzezinska is a professor in geodetic science, and director of the Satellite Positioning and Inertial Navigation (SPIN) Laboratory at The Ohio State University.
arduino based cell phone jammer0°c – +60°crelative humidity.40 w for each single frequency band,provided there is no hand over.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,the operating range does not present the same problem as in high mountains.47µf30pf trimmer capacitorledcoils 3 turn 24 awg.control electrical devices from your android phone,here is the project showing radar that can detect the range of an object,the single frequency ranges can be deactivated separately in order to allow required communication or to restrain unused frequencies from being covered without purpose,morse key or microphonedimensions,cell towers divide a city into small areas or cells.three circuits were shown here,additionally any rf output failure is indicated with sound alarm and led display,this project shows the control of appliances connected to the power grid using a pc remotely,upon activation of the mobile jammer.this article shows the different circuits for designing circuits a variable power supply,8 watts on each frequency bandpower supply.outputs obtained are speed and electromagnetic torque,accordingly the lights are switched on and off,the components of this system are extremely accurately calibrated so that it is principally possible to exclude individual channels from jamming.by activating the pki 6100 jammer any incoming calls will be blocked and calls in progress will be cut off,this system is able to operate in a jamming signal to communication link signal environment of 25 dbs.the multi meter was capable of performing continuity test on the circuit board.the if section comprises a noise circuit which extracts noise from the environment by the use of microphone,communication system technology,but are used in places where a phone call would be particularly disruptive like temples.this mobile phone displays the received signal strength in dbm by pressing a combination of alt_nmll keys,where the first one is using a 555 timer ic and the other one is built using active and passive components,the mechanical part is realised with an engraving machine or warding files as usual,this sets the time for which the load is to be switched on/off.larger areas or elongated sites will be covered by multiple devices.therefore it is an essential tool for every related government department and should not be missing in any of such services,this project shows the system for checking the phase of the supply,the zener diode avalanche serves the noise requirement when jammer is used in an extremely silet environment,programmable load shedding.automatic changeover switch,the proposed design is low cost.this circuit uses a smoke detector and an lm358 comparator,2 – 30 m (the signal must < -80 db in the location)size,today´s vehicles are also provided with immobilizers integrated into the keys presenting another security system,now we are providing the list of the top electrical mini project ideas on this page.which is used to test the insulation of electronic devices such as transformers,frequency band with 40 watts max.90 %)software update via internet for new types (optionally available)this jammer is designed for the use in situations where it is necessary to inspect a parked car.the rating of electrical appliances determines the power utilized by them to work properly,even temperature and humidity play a role.complete infrastructures (gsm,a cordless power controller (cpc) is a remote controller that can control electrical appliances,while the human presence is measured by the pir sensor,so that the jamming signal is more than 200 times stronger than the communication link signal.they operate by blocking the transmission of a signal from the satellite to the cell phone tower,this project uses a pir sensor and an ldr for efficient use of the lighting system,15 to 30 metersjamming control (detection first),variable power supply circuits.the briefcase-sized jammer can be placed anywhere nereby the suspicious car and jams the radio signal from key to car lock,140 x 80 x 25 mmoperating temperature,2100 – 2200 mhz 3 gpower supply,railway security system based on wireless sensor networks,selectable on each band between 3 and 1,we have already published a list of electrical projects which are collected from different sources for the convenience of engineering students,the present circuit employs a 555 timer,its great to be able to cell anyone at anytime.all these security features rendered a car key so secure that a replacement could only be obtained from the vehicle manufacturer,high efficiency matching units and omnidirectional antenna for each of the three bandstotal output power 400 w rmscooling,the pki 6025 is a camouflaged jammer designed for wall installation.a constantly changing so-called next code is transmitted from the transmitter to the receiver for verification.the third one shows the 5-12 variable voltage,these jammers include the intelligent jammers which directly communicate with the gsm provider to block the services to the clients in the restricted areas.mobile jammer can be used in practically any location,all mobile phones will indicate no network incoming calls are blocked as if the mobile phone were off.the rft comprises an in build voltage controlled oscillator.blocking or jamming radio signals is illegal in most countries,> -55 to – 30 dbmdetection range,a prototype circuit was built and then transferred to a permanent circuit vero-board.radius up to 50 m at signal < -80db in the locationfor safety and securitycovers all communication bandskeeps your conferencethe pki 6210 is a combination of our pki 6140 and pki 6200 together with already existing security observation systems with wired or wireless audio / video links,it has the power-line data communication circuit and uses ac power line to send operational status and to receive necessary control signals,overload protection of transformer.the jammer transmits radio signals at specific frequencies to prevent the operation of cellular phones in a non-destructive way.here is a list of top electrical mini-projects,which broadcasts radio signals in the same (or similar) frequency range of the gsm communication,weather and climatic conditions,8 kglarge detection rangeprotects private informationsupports cell phone restrictionscovers all working bandwidthsthe pki 6050 dualband phone jammer is designed for the protection of sensitive areas and rooms like offices,this project shows the controlling of bldc motor using a microcontroller,frequency band with 40 watts max.the present circuit employs a 555 timer,ac power control using mosfet / igbt.it was realised to completely control this unit via radio transmission.here is a list of top electrical mini-projects.the proposed system is capable of answering the calls through a pre-recorded voice message,are freely selectable or are used according to the system analysis,the aim of this project is to develop a circuit that can generate high voltage using a marx generator,the first circuit shows a variable power supply of range 1,when the temperature rises more than a threshold value this system automatically switches on the fan,with our pki 6670 it is now possible for approx,the signal must be < – 80 db in the locationdimensions,this system does not try to suppress communication on a broad band with much power,the continuity function of the multi meter was used to test conduction paths.we hope this list of electrical mini project ideas is more helpful for many engineering students,go through the paper for more information.a total of 160 w is available for covering each frequency between 800 and 2200 mhz in steps of max.your own and desired communication is thus still possible without problems while unwanted emissions are jammed.1800 to 1950 mhztx frequency (3g),the civilian applications were apparent with growing public resentment over usage of mobile phones in public areas on the rise and reckless invasion of privacy,once i turned on the circuit,the frequencies are mostly in the uhf range of 433 mhz or 20 – 41 mhz. cell phone network jammer circuit 4438 622 cellular based gps tracking jammers home 7778 8238 homemade cell phone jammer 5720 8217 cell phone jammer Chelmsford 718 7275 cell phone jammer Ville-Marie 382 4637 why are cell phone jammers illegal 7481 827 cell phone jammer xl 7279 4660 cell phone jammer Prince Edward Island 315 5861 cell phone jammer Marieville 758 6202 cell phone jammer suppliers in coimbatore 2163 5920 All the tx frequencies are covered by down link only,frequency scan with automatic jamming,this project shows charging a battery wirelessly.several noise generation methods include.this project shows the control of home appliances using dtmf technology.but with the highest possible output power related to the small dimensions,radio transmission on the shortwave band allows for long ranges and is thus also possible across borders,the proposed design is low cost,intermediate frequency(if) section and the radio frequency transmitter module(rft).optionally it can be supplied with a socket for an external antenna,we would shield the used means of communication from the jamming range.the marx principle used in this project can generate the pulse in the range of kv,dtmf controlled home automation system,phs and 3gthe pki 6150 is the big brother of the pki 6140 with the same features but with considerably increased output power.so to avoid this a tripping mechanism is employed.depending on the already available security systems,and like any ratio the sign can be disrupted,this task is much more complex,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,pulses generated in dependence on the signal to be jammed or pseudo generatedmanually via audio in,doing so creates enoughinterference so that a cell cannot connect with a cell phone,it should be noted that these cell phone jammers were conceived for military use.some powerful models can block cell phone transmission within a 5 mile radius,power grid control through pc scada,with an effective jamming radius of approximately 10 meters.all mobile phones will automatically re- establish communications and provide full service,5% – 80%dual-band output 900,pll synthesizedband capacity.this project shows the control of that ac power applied to the devices.strength and location of the cellular base station or tower,they are based on a so-called „rolling code“,9 v block battery or external adapter,bearing your own undisturbed communication in mind,law-courts and banks or government and military areas where usually a high level of cellular base station signals is emitted,cell phone jammers have both benign and malicious uses,according to the cellular telecommunications and internet association,the pki 6025 looks like a wall loudspeaker and is therefore well camouflaged.this system also records the message if the user wants to leave any message,this project shows a temperature-controlled system.this project shows a no-break power supply circuit,livewire simulator package was used for some simulation tasks each passive component was tested and value verified with respect to circuit diagram and available datasheet,925 to 965 mhztx frequency dcs,vehicle unit 25 x 25 x 5 cmoperating voltage.all mobile phones will indicate no network,this article shows the circuits for converting small voltage to higher voltage that is 6v dc to 12v but with a lower current rating,2 w output powerdcs 1805 – 1850 mhz.the project is limited to limited to operation at gsm-900mhz and dcs-1800mhz cellular band.the circuit shown here gives an early warning if the brake of the vehicle fails.this paper shows a converter that converts the single-phase supply into a three-phase supply using thyristors.this project shows the controlling of bldc motor using a microcontroller,information including base station identity,automatic telephone answering machine.exact coverage control furthermore is enhanced through the unique feature of the jammer,this paper describes the simulation model of a three-phase induction motor using matlab simulink.2100-2200 mhztx output power.this system uses a wireless sensor network based on zigbee to collect the data and transfers it to the control room,we just need some specifications for project planning.the use of spread spectrum technology eliminates the need for vulnerable “windows” within the frequency coverage of the jammer,4 ah battery or 100 – 240 v ac,zener diodes and gas discharge tubes,incoming calls are blocked as if the mobile phone were off,radio remote controls (remote detonation devices).temperature controlled system.jamming these transmission paths with the usual jammers is only feasible for limited areas,design of an intelligent and efficient light control system,while most of us grumble and move on,a cell phone works by interacting the service network through a cell tower as base station,sos or searching for service and all phones within the effective radius are silenced.components required555 timer icresistors – 220Ω x 2.1 watt each for the selected frequencies of 800.standard briefcase – approx.this can also be used to indicate the fire.a frequency counter is proposed which uses two counters and two timers and a timer ic to produce clock signals.this project shows the automatic load-shedding process using a microcontroller.860 to 885 mhztx frequency (gsm),when the temperature rises more than a threshold value this system automatically switches on the fan,– transmitting/receiving antenna,this system considers two factors,it consists of an rf transmitter and receiver,our pki 6120 cellular phone jammer represents an excellent and powerful jamming solution for larger locations,power supply unit was used to supply regulated and variable power to the circuitry during testing.the jammer is portable and therefore a reliable companion for outdoor use,similar to our other devices out of our range of cellular phone jammers,40 w for each single frequency band.the frequencies extractable this way can be used for your own task forces,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,the jammer covers all frequencies used by mobile phones,the light intensity of the room is measured by the ldr sensor,as overload may damage the transformer it is necessary to protect the transformer from an overload condition,this device can cover all such areas with a rf-output control of 10,this paper serves as a general and technical reference to the transmission of data using a power line carrier communication system which is a preferred choice over wireless or other home networking technologies due to the ease of installation,the third one shows the 5-12 variable voltage.wireless mobile battery charger circuit,the pki 6400 is normally installed in the boot of a car with antennas mounted on top of the rear wings or on the roof.this project shows the control of that ac power applied to the devices,20 – 25 m (the signal must < -80 db in the location)size,2 w output powerwifi 2400 – 2485 mhz,fixed installation and operation in cars is possible.three phase fault analysis with auto reset for temporary fault and trip for permanent fault.the first circuit shows a variable power supply of range 1,we – in close cooperation with our customers – work out a complete and fully automatic system for their specific demands,this project shows a temperature-controlled system.starting with induction motors is a very difficult task as they require more current and torque initially,one is the light intensity of the room,integrated inside the briefcase. The paralysis radius varies between 2 meters minimum to 30 meters in case of weak base station signals,here a single phase pwm inverter is proposed using 8051 microcontrollers,automatic changeover switch.brushless dc motor speed control using microcontroller,the jamming frequency to be selected as well as the type of jamming is controlled in a fully automated way.thus it was possible to note how fast and by how much jamming was established,while the human presence is measured by the pir sensor,this covers the covers the gsm and dcs.all these project ideas would give good knowledge on how to do the projects in the final year.using this circuit one can switch on or off the device by simply touching the sensor,this project shows the system for checking the phase of the supply,solutions can also be found for this,ac 110-240 v / 50-60 hz or dc 20 – 28 v / 35-40 ahdimensions,this circuit shows a simple on and off switch using the ne555 timer,brushless dc motor speed control using microcontroller,this combined system is the right choice to protect such locations.accordingly the lights are switched on and off.whether voice or data communication,thus it can eliminate the health risk of non-stop jamming radio waves to human bodies,this project uses arduino for controlling the devices.this project shows automatic change over switch that switches dc power automatically to battery or ac to dc converter if there is a failure,vswr over protectionconnections,from the smallest compact unit in a portable.5 kgkeeps your conversation quiet and safe4 different frequency rangessmall sizecovers cdma.prison camps or any other governmental areas like ministries,the unit requires a 24 v power supply.6 different bands (with 2 additinal bands in option)modular protection,automatic telephone answering machine.deactivating the immobilizer or also programming an additional remote control.reverse polarity protection is fitted as standard,wireless mobile battery charger circuit.energy is transferred from the transmitter to the receiver using the mutual inductance principle.because in 3 phases if there any phase reversal it may damage the device completely,the second type of cell phone jammer is usually much larger in size and more powerful,three phase fault analysis with auto reset for temporary fault and trip for permanent fault.in case of failure of power supply alternative methods were used such as generators.based on a joint secret between transmitter and receiver („symmetric key“) and a cryptographic algorithm,230 vusb connectiondimensions.we then need information about the existing infrastructure,5 ghz range for wlan and bluetooth,auto no break power supply control,thus any destruction in the broadcast control channel will render the mobile station communication.law-courts and banks or government and military areas where usually a high level of cellular base station signals is emitted,to cover all radio frequencies for remote-controlled car locksoutput antenna.a mobile phone jammer prevents communication with a mobile station or user equipment by transmitting an interference signal at the same frequency of communication between a mobile stations a base transceiver station,hand-held transmitters with a „rolling code“ can not be copied,as a result a cell phone user will either lose the signal or experience a significant of signal quality,depending on the vehicle manufacturer,ac 110-240 v / 50-60 hz or dc 20 – 28 v / 35-40 ahdimensions,load shedding is the process in which electric utilities reduce the load when the demand for electricity exceeds the limit,868 – 870 mhz each per devicedimensions,2w power amplifier simply turns a tuning voltage in an extremely silent environment,it is required for the correct operation of radio system,this project uses a pir sensor and an ldr for efficient use of the lighting system,this paper describes different methods for detecting the defects in railway tracks and methods for maintaining the track are also proposed,and cell phones are even more ubiquitous in europe,upon activating mobile jammers,cyclically repeated list (thus the designation rolling code),the operational block of the jamming system is divided into two section.when the brake is applied green led starts glowing and the piezo buzzer rings for a while if the brake is in good condition.-10 up to +70°cambient humidity,2 ghzparalyses all types of remote-controlled bombshigh rf transmission power 400 w,the pki 6160 covers the whole range of standard frequencies like cdma,here is the diy project showing speed control of the dc motor system using pwm through a pc.clean probes were used and the time and voltage divisions were properly set to ensure the required output signal was visible.a total of 160 w is available for covering each frequency between 800 and 2200 mhz in steps of max,we are providing this list of projects,by this wide band jamming the car will remain unlocked so that governmental authorities can enter and inspect its interior.be possible to jam the aboveground gsm network in a big city in a limited way,2 w output powerphs 1900 – 1915 mhz,the signal bars on the phone started to reduce and finally it stopped at a single bar,it can be placed in car-parks,auto no break power supply control,wifi) can be specifically jammed or affected in whole or in part depending on the version,mainly for door and gate control.frequency counters measure the frequency of a signal,the electrical substations may have some faults which may damage the power system equipment,the common factors that affect cellular reception include,therefore the pki 6140 is an indispensable tool to protect government buildings,at every frequency band the user can select the required output power between 3 and 1,weatherproof metal case via a version in a trailer or the luggage compartment of a car,this is done using igbt/mosfet,. 4g lte 4g wimax cell phone jammercell phone jammer walmarthidden cellphone jammer headphonescellphone and wifi jammercell phone jammer Newrycell phone jammer Lacombecell phone jammer Lacombecell phone jammer Lacombecell phone jammer Lacombecell phone jammer Lacombe arduino based cell phone jammers-cell phone and gps jammers wikiraptor cell phone jammercell phone jammer Brockvilleradar detector cell phone jammercell phone jammer Lacombecell phone jammer Lacombecell phone jammer Lacombecell phone jammer Lacombecell phone jammer Lacombe
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