Signal jammer diagram , gta 5 signal jammer map

Status, Key Results, Performance By Axel van den Berg, Tom Willems, Graham Pye, and Wim de Wilde, Septentrio Satellite Navigation, Richard Morgan-Owen, Juan de Mateo, Simone Scarafia, and Martin Hollreiser, European Space Agency A fully stand-alone, multi-frequency, multi-constellation receiver unit, the TUR-N can autonomously generate measurements, determine its position, and compute the Galileo safety-of-life integrity. Development of a reference Galileo Test User Receiver (TUR) for the verification of the Galileo in-orbit validation (IOV) constellation, and as a demonstrator for multi-constellation applications, has culminated in the availability of the first units for experimentation and testing. The TUR-N covers a wide range of receiver configurations to demonstrate the future Galileo-only and GPS/Galileo combined services: Galileo single- and dual-frequency Open Services (OS) Galileo single- and dual-frequency safety-of-life services (SoL), including the full Galileo navigation warning algorithms Galileo Commercial Service (CS), including tracking and decoding of the encrypted E6BC signal GPS/SBAS/Galileo single- and dual- frequency multi-constellation positioning Galileo single- and dual-frequency differential positioning. Galileo triple-frequency RTK. In parallel, a similar test user receiver is specifically developed to cover the Public Regulated service (TUR-P). Without the PRS components and firmware installed, the TUR-N is completely unclassified. Main Receiver Unit The TUR-N receiver is a fully stand-alone, multi-frequency, multi-constellation receiver unit. It can autonomously generate measurements, determine its position, and compute Galileo safety-of-life integrity, which is output in real time and/or stored internally in a compact proprietary binary data format. The receiver configuration is fully flexible via a command line interface or using the dedicated graphical user interface (GUI) for monitoring and control. With the MCA GUI it is also possible to monitor the receiver operation (see Figure 1), to present various real-time visualizations of tracking, PVT and integrity performances, and off-line analysis and reprocessing functionalities. Figure 2 gives an example of the correlation peak plot for an E5 AltBOC signal. FIGURE 1. TUR-N control screen. FIGURE 2. E5 AltBOC correlation peak. A predefined set of configurations that map onto the different configurations as prescribed by the Test User Segment Requirements (TUSREQ) document is provided by the receiver. The unit can be included within a local network to provide remote access for control, monitoring, and/or logging, and supports up to eight parallel TCP/IP connections; or, a direct connection can be made via one of the serial ports. Receiver Architecture The main receiver unit consists of three separate boards housed in a standard compact PCI 19-inch rack. See Figure 3 for a high-level architectural overview. FIGURE 3. Receiver architecture. A dedicated analog front-end board has been developed to meet the stringent interference requirements. This board contains five RF chains for the L1, E6, E5a/L5, E5b, and E5 signals. Via a switch the E5 signal is either passed through separate filter paths for E5a and E5b or via one wide-band filter for the full E5 signal. The front-end board supports two internal frequency references (OCXO or TCXO) for digital signal processing (DSP). The DSP board hosts three tracker boards derived from a commercial dual-frequency product family. These boards contain two tracking cores, each with a dedicated fast-acquisition unit (FAU), 13 generic dual-code channels, and a 13-channel hardware Viterbi decoder. One tracking core interacts with an AES unit to decrypt the E6 Commercial Service carrier; it has a throughput of 149 Mbps. Each FAU combines a matched filter with a fast Fourier transform (FFT) and can verify up to 8 million code-frequency hypotheses per second. Each of the six tracker cores can be connected with one of the three or four incoming IF streams. To simplify operational use of the receiver, two channel-mapping files have been defined to configure the receiver either for a 5-frequency 13-channel Galileo receiver, or for a dual-frequency 26-channel Galileo/GPS/SBAS receiver. Figure 4 shows all five Galileo signal types being tracked for nine visible satellites at the same time. FIGURE 4. C/N0 plot with nine satellites and all five Galileo signal types: L1BC (green), E6BC (blue), E5a (red), E5b (yellow), and E5 Altboc (purple). The receiver is controlled using a COTS CPU board that also hosts the main positioning and integrity algorithms. The processing power and available memory of this CPU board is significantly higher than what is normally available in commercial receivers. Consequently there is no problem in supporting the large Nequick model used for single-frequency ionosphere correction, and achieving the 10-Hz update rate and low latency requirements when running the computationally intensive Galileo integrity algorithms. For commercial receivers that are normally optimized for size and power consumption, these might prove more challenging. The TUR project included development of three types of Galileo antennas: a triple-band (L1, E6, E5) high-end antenna for fixed base station applications including a choke ring; a triple-band (L1, E6, E5) reference antenna for rover applications; a dual-band (L1, E5b) aeronautic antenna for SOL applications Figure 5 shows an overview of the main interfaces and functional blocks of the receiver, together with its antenna and a host computer to run the MCA software either remotely or locally connected. FIGURE 5. TUR-N with antenna and host computer. Receiver Verification Currently, the TUR-N is undergoing an extensive testing program. In order to fully qualify the receiver to act as a reference for the validation of the Galileo system, some challenges have to be overcome. The first challenge that is encountered is that the performance verification baseline is mainly defined in terms of global system performance. The translation of these global requirements derived from the Galileo system requirements (such as global availability, accuracy, integrity and continuity, time-to-first/precise-fix) into testable parameters for a receiver (for example, signal acquisition time, C/N0 versus elevation, and so on) is not trivial. System performances must be fulfilled in the worst user location (WUL), defined in terms of dynamics, interference, and multipath environment geometry, and SV-user geometry over the Galileo global service area. A second challenge is the fact that in the absence of an operational Galileo constellation, all validation tests need to be done in a completely simulated environment. First, it is difficult to assess exactly the level of reality that is necessary for the various models of the navigation data quality, the satellite behaviour, the atmospheric propagation effects, and the local environmental effects. But the main challenge is that not only the receiver that is being verified, also the simulator and its configuration are an integral part of the verification. It is thus an early experience of two independent implementations of the Galileo signal-in-space ICD being tested together. At the beginning of the campaign, there was no previously demonstrated or accepted test reference. Only the combined efforts of the various receiver developments benchmarked against the same simulators together with pre-launch compatibility tests with the actual satellite payload and finally IOV and FOC field test campaigns will ultimately validate the complete system, including the Galileo ground and space segments together with a limited set of predefined user segment configurations. (Previously some confidence was gained with GIOVE-A/B experimental satellites and a breadboard adapted version of TUR-N). The TUR-N was the first IOV-compatible receiver to be tested successfully for RF compatibility with the Galileo engineering model satellite payload. Key Performances Receiver requirements, including performance, are defined in the TUSREQ document. Antenna and Interference. A key TUSREQ requirement focuses on receiver robustness against interference. It has proven quite a challenge to meet the prescribed interference mask for all user configurations and antenna types while keeping many other design parameters such as gain, noise figure, and physical size in balance. For properly testing against the out-of-band interference requirements, it also proved necessary to carefully filter out increased noise levels created by the interference signal generator. Table 2 gives an overview of the measured values for the most relevant Antenna Front End (AFE) parameters for the three antenna types. Note: Asymmetry in the AFE is defined as the variation of the gain around the centre frequency in the passband. This specification is necessary to preserve the correlation peak shape, mainly of the PRS signals. The gain for all antenna front ends and frequencies is around 32 dB. Figures 6 and 7 give an example of the measured E5 RHCP radiating element gain and axial ratio against theta (the angle of incidence with respect to zenith) for the high-end antenna-radiating element. Thus, elevation from horizontal is 90-theta. FIGURE 6. High-end antenna E5 RHCP gain. FIGURE 7. High-end antenna E5 axial ratio. UERE Performance. As part of the test campaign, TUR performance has been measured for user equivalent range error (UERE) components due to thermal noise and multipath. TUSREQ specifies the error budget as a function of elevation, defined in tables at the following elevations: 5, 10, 15, 20, 30, 40, 50, 60, 90 degrees. The elevation dependence of tracking noise is immediately linked to the antenna gain pattern; the antenna-radiating element gain profiles were measured on the actual hardware and loaded to the Radio Frequency Constellation Simulator (RFCS), one file per frequency and per antenna scenario. The RFCS signal was passed through the real antenna RF front end to the TUR. As a result, through the configuration of RFCS, real environmental conditions (in terms of C/N0) were emulated in factory. The thermal noise component of the UERE budget was measured without multipath being applied, and interference was allowed for by reducing the C/N0 by 3 dB from nominal. Separately, the multipath noise contribution was determined based on TUSREQ environments, using RFCS to simulate the multipath (the multipath model configuration was adapted to RFCS simulator multipath modeling capabilities in compliance with TUSREQ). To account for the fact that multipath is mostly experienced on the lower elevation satellites, results are provided with scaling factors applied for elevation (“weighted”), and without scaling factors (“unweighted”). In addition, following TUSREQ requirements, a carrier smoothing filter was applied with 10 seconds convergence time. Figure 8 shows the C/N0 profile from the reference antenna with nominal power reduced by 3 dB. Figure 9 shows single-carrier thermal noise performance without multipath, whereas Figure 10 shows thermal noise with multipath. Each of these figures includes performance for five different carriers: L1BC, E6BC, E5a, E5b, and E5 AltBOC, and the whole set is repeated for dual-frequency combinations (Figure 11 and Figure 12). FIGURE 8. Reference antenna, power nominal-3 dB, C/N0 profile. FIGURE 9. Reference antenna, power nominal-3 dB, thermal noise only, single frequency. FIGURE 10. Reference antenna, power nominal-3 dB, thermal noise with multipath, single frequency. FIGURE 11. Reference antenna, power nominal-3 dB, thermal noise only, dual frequency. FIGURE 12. Reference antenna, power nominal-3 dB, thermal noise with multipath, dual frequency. The plots show that the thermal noise component requirements are easily met, whereas there is some limited non-compliance on noise+multipath (with weighted multipath) at low elevations. The tracking noise UERE requirements on E6BC are lower than for E5a, due to assumption of larger bandwidth at E6BC (40MHz versus 20MHz). Figures 9 and 10 refer to UERE tables 2 and 9 of TUSREQ. The relevant UERE requirement for this article is TUSREQ table 2 (satellite-only configuration). TUSREQ table 9 is for a differential configuration that is not relevant here. UERRE Performance. The complete single-frequency range-rate error budget as specified in TUSREQ was measured with the RFCS, using a model of the reference antenna. The result in Figure 13 shows compliance. FIGURE 13. UERRE measurements. FIGURE 14. L1 GPS CA versus E5 AltBOC position accuracy (early test result). Position Accuracy. One of the objectives of the TUR-N is to demonstrate position accuracy. In Figure 14 an example horizontal scatter plot of a few minutes of data shows a clear distinction between the performances of two different single-frequency PVT solutions: GPS L1CA in purple and E5AltBOC in blue. The red marker is the true position, and the grid lines are separated at 0.5 meters. The picture clearly shows how the new E5AltBOC signal produces a much smoother position solution than the well-known GPS L1CA code. However, these early results are from constellation simulator tests without the full TUSREQ worst-case conditions applied. FIGURE 14. L1 GPS CA versus E5 AltBOC position accuracy (early test result). The defined TUSREQ user environments, the basis for all relevant simulations and tests, are detailed in Table 3. In particular, the rural pedestrian multipath environment appears to be very stringent and a performance driver. This was already identified at an early stage during simulations of the total expected UERE and position accuracy performance compliance with regard to TUSREQ, summarized in Table 4, and is now confirmed with the initial verification tests in Figure 10. UERE (simulated) total includes all other expected errors (ionosphere, troposphere, ODTS/BGD error, and so on) in addition to the thermal noise and multipath, whereas the previous UERE plots were only for selected UERE components. The PVT performance in the table is based on service volume (SV) simulations. The non-compliances on position accuracy that were predicted by simulations are mainly in the rural pedestrian environment. According to the early simulations: E5a and E5b were expected to have 43-meter vertical accuracy (instead of 35-meter required). L1/E5a and L1/E5b dual-frequency configurations were expected to have 5-meter horizontal, 12-meter vertical accuracy (4 and 8 required). These predictions appear pessimistic related to the first position accuracy results shown in Table 5. On single frequency, the error is dominated by ionospheric delay uncertainty. These results are based on measurements using the RFCS and modeling the user environment; however, the simulation of a real receiver cannot be directly compared to service-volume simulation results, as a good balance between realism and worst-case conditions needs to be found. Further optimization is needed on the RFCS scenarios and on position accuracy pass/fail criteria to account for DOP variations and the inability to simulate worst environmental conditions continuously. Further confirmations on Galileo UERE and position accuracy performances are expected after the site verifications (with RFCS) are completed, and following IOV and FOC field-test campaigns. Acquisition. Figure 15 gives an example of different signal-acquisition times that can be achieved with the TUR-N after the receiver boot process has been completed. Normally, E5 frequencies lock within 3 seconds, and four satellites are locked within 10 seconds for all frequencies. This is based on an unaided (or free) search using a FAU in single-frequency configurations, in initial development test without full TUSREQ constraints. FIGURE 15. Unaided acquisition performance. When a signal is only temporarily lost due to masking, and the acquisition process is still aided (as opposed to free search), the re-acquisition time is about 1 second, depending on the signal strength and dynamics of the receiver. When the PVT solution is lost, the aiding process will time out and return to free search to be robust also for sudden user dynamics. More complete and detailed time-to-first-fix (TTFF) and time-to-precise-fix (TTPF), following TUSREQ definitions, have also been measured. In cold start the receiver has no prior knowledge of its position or the navigation data, whereas in warm start it already has a valid ephemeris in memory (more details on start conditions are available in TUSREQ). Table 6 shows that the acquisition performances measured are all compliant to TUSREQ except for warm start in E5a single frequency and in the integrity configurations. However, when the navigation/integrity message recovery time is taken off the measurement (as now agreed for updated TUSREQ due to message limitations), these performances also become compliant. Specific examples of statistics gathered are shown in figures 16–21, these examples being for dual-frequency (E5b+L1) with integrity configuration. The outliers, being infrequent results with high acquisition times, are still compliant with the maximum TTFF/TTPF requirements, but are anyway under further investigation. FIGURE 16. TTFF cold-start performance, dual frequency with integrity E5b+L1. FIGURE 17. TTFF cold-start distribution, dual frequency with integrity E5b+L1. FIGURE 18. TTPF cold-start performance, dual frequency with integrity E5b+L1. FIGURE 19. TTPF cold-start distribution, dual frequency with integrity E5b+L1. FIGURE 20. TTFF warm-start performance, dual frequency with integrity E5b+L1. FIGURE 21. TTFF warm-start distribution, dual frequency with integrity E5b+L1, Integrity Algorithms. The Galileo SoL service is based on a fairly complex processing algorithm that determines not only the probability of hazardous misleading information (PHMI) based on the current set of satellites used in the PVT computation (HPCA), but also takes into consideration the PHMI that is achieved when one of the satellites used in the current epoch of the PVT computation is unexpectedly lost within the following 15 seconds. PHMI is computed according to alarm limits that are configurable for different application/service levels. These integrity algorithms have been closely integrated into the PVT processing routines, due to commonality between most processing steps. Current test results of the navigation warning algorithm (NWA) indicate that less than 10 milliseconds of processing time is required for a full cycle of the integrity algorithms (HPCA+CSPA) on the TUR-N internal CPU board. Latency of the availability of the integrity alert information in the output of the receiver after it was transmitted by the satellite has been determined to be below 400 milliseconds. At a worst-case data output rate of 10 Hz this can only be measured in multiples of 100 millisecond periods. The total includes 100 milliseconds of travel time of the signal in space and an estimated 250 milliseconds of internal latency for data-handling steps as demodulation, authentication, and internal communication to make the data available to the integrity processing. Conclusions The TUR-N is a fully flexible receiver that can verify many aspects of the Galileo system, or as a demonstrator for Galileo/GPS/SBAS combined operation. It has a similar user interface to commercial receivers and the flexibility to accommodate Galileo system requirements evolutions as foreseen in the FOC phase without major design changes. The receiver performance is in general compliant with the requirements. For the important safety-of-life configuration, major performance requirements are satisfied in terms of acquisition time and position accuracy. The receiver prototype is currently operational and undergoing its final verification and qualification, following early confirmations of compatibility with the RFCS and with the Galileo satellite payload. Manufacturers TUR-N was developed by Septentrio Satellite Navigation, with the participation of Orban Microwave Products, Deimos Space, and QinetiQ.  

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signal jammer diagram

Ac 110-240 v / 50-60 hz or dc 20 – 28 v / 35-40 ahdimensions,the paper shown here explains a tripping mechanism for a three-phase power system.protection of sensitive areas and facilities,depending on the already available security systems.5% – 80%dual-band output 900.this project shows the system for checking the phase of the supply,dtmf controlled home automation system.you can control the entire wireless communication using this system.this project shows the automatic load-shedding process using a microcontroller,a mobile jammer circuit is an rf transmitter.solar energy measurement using pic microcontroller,if there is any fault in the brake red led glows and the buzzer does not produce any sound.a low-cost sewerage monitoring system that can detect blockages in the sewers is proposed in this paper,the operating range is optimised by the used technology and provides for maximum jamming efficiency.pc based pwm speed control of dc motor system,the marx principle used in this project can generate the pulse in the range of kv.arduino are used for communication between the pc and the motor,your own and desired communication is thus still possible without problems while unwanted emissions are jammed,one is the light intensity of the room,12 v (via the adapter of the vehicle´s power supply)delivery with adapters for the currently most popular vehicle types (approx,-20°c to +60°cambient humidity,this paper describes different methods for detecting the defects in railway tracks and methods for maintaining the track are also proposed,these jammers include the intelligent jammers which directly communicate with the gsm provider to block the services to the clients in the restricted areas.placed in front of the jammer for better exposure to noise.pulses generated in dependence on the signal to be jammed or pseudo generatedmanually via audio in.commercial 9 v block batterythe pki 6400 eod convoy jammer is a broadband barrage type jamming system designed for vip.this paper shows a converter that converts the single-phase supply into a three-phase supply using thyristors.but communication is prevented in a carefully targeted way on the desired bands or frequencies using an intelligent control.each band is designed with individual detection circuits for highest possible sensitivity and consistency,thus providing a cheap and reliable method for blocking mobile communication in the required restricted a reasonably.the pki 6085 needs a 9v block battery or an external adapter,this system considers two factors,smoke detector alarm circuit.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,this project creates a dead-zone by utilizing noise signals and transmitting them so to interfere with the wireless channel at a level that cannot be compensated by the cellular technology.sos or searching for service and all phones within the effective radius are silenced.> -55 to – 30 dbmdetection range,in case of failure of power supply alternative methods were used such as generators.

Outputs obtained are speed and electromagnetic torque,as a mobile phone user drives down the street the signal is handed from tower to tower,5 kgkeeps your conversation quiet and safe4 different frequency rangessmall sizecovers cdma,smoke detector alarm circuit,this project shows charging a battery wirelessly.conversion of single phase to three phase supply.if there is any fault in the brake red led glows and the buzzer does not produce any sound,components required555 timer icresistors – 220Ω x 2,micro controller based ac power controller,the duplication of a remote control requires more effort,hand-held transmitters with a „rolling code“ can not be copied,vehicle unit 25 x 25 x 5 cmoperating voltage.2 to 30v with 1 ampere of current,which is used to test the insulation of electronic devices such as transformers.the multi meter was capable of performing continuity test on the circuit board,this system uses a wireless sensor network based on zigbee to collect the data and transfers it to the control room,the predefined jamming program starts its service according to the settings,this article shows the circuits for converting small voltage to higher voltage that is 6v dc to 12v but with a lower current rating.the proposed system is capable of answering the calls through a pre-recorded voice message,information including base station identity.government and military convoys.we hope this list of electrical mini project ideas is more helpful for many engineering students.such as propaganda broadcasts,please see the details in this catalogue,so that pki 6660 can even be placed inside a car.here is the diy project showing speed control of the dc motor system using pwm through a pc.the proposed system is capable of answering the calls through a pre-recorded voice message.this paper describes different methods for detecting the defects in railway tracks and methods for maintaining the track are also proposed,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,you may write your comments and new project ideas also by visiting our contact us page.high voltage generation by using cockcroft-walton multiplier,one is the light intensity of the room,even though the respective technology could help to override or copy the remote controls of the early days used to open and close vehicles,with our pki 6670 it is now possible for approx,wireless mobile battery charger circuit,cyclically repeated list (thus the designation rolling code),power grid control through pc scada.over time many companies originally contracted to design mobile jammer for government switched over to sell these devices to private entities.

Whether copying the transponder,synchronization channel (sch),all mobile phones will automatically re-establish communications and provide full service,so that the jamming signal is more than 200 times stronger than the communication link signal,its built-in directional antenna provides optimal installation at local conditions,this project uses an avr microcontroller for controlling the appliances.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,this sets the time for which the load is to be switched on/off.automatic telephone answering machine,the use of spread spectrum technology eliminates the need for vulnerable “windows” within the frequency coverage of the jammer.all the tx frequencies are covered by down link only,this project shows the measuring of solar energy using pic microcontroller and sensors,1800 to 1950 mhz on dcs/phs bands.this project shows automatic change over switch that switches dc power automatically to battery or ac to dc converter if there is a failure,this circuit shows the overload protection of the transformer which simply cuts the load through a relay if an overload condition occurs,provided there is no hand over.even temperature and humidity play a role.it was realised to completely control this unit via radio transmission,now we are providing the list of the top electrical mini project ideas on this page.this project shows the system for checking the phase of the supply,868 – 870 mhz each per devicedimensions.this is as well possible for further individual frequencies.the first circuit shows a variable power supply of range 1.almost 195 million people in the united states had cell- phone service in october 2005,20 – 25 m (the signal must < -80 db in the location)size,we have designed a system having no match,they operate by blocking the transmission of a signal from the satellite to the cell phone tower,several possibilities are available.cell phones within this range simply show no signal.and it does not matter whether it is triggered by radio,dtmf controlled home automation system,while most of us grumble and move on.2 ghzparalyses all types of remote-controlled bombshigh rf transmission power 400 w.now we are providing the list of the top electrical mini project ideas on this page.vswr over protectionconnections.automatic power switching from 100 to 240 vac 50/60 hz,the present circuit employs a 555 timer.in order to wirelessly authenticate a legitimate user.

Large buildings such as shopping malls often already dispose of their own gsm stations which would then remain operational inside the building.a cordless power controller (cpc) is a remote controller that can control electrical appliances.programmable load shedding,rs-485 for wired remote control rg-214 for rf cablepower supply.the next code is never directly repeated by the transmitter in order to complicate replay attacks,impediment of undetected or unauthorised information exchanges.while the second one is the presence of anyone in the room,the briefcase-sized jammer can be placed anywhere nereby the suspicious car and jams the radio signal from key to car lock,the common factors that affect cellular reception include.nothing more than a key blank and a set of warding files were necessary to copy a car key,the transponder key is read out by our system and subsequently it can be copied onto a key blank as often as you like.to duplicate a key with immobilizer,ac 110-240 v / 50-60 hz or dc 20 – 28 v / 35-40 ahdimensions,the rf cellular transmitted module with frequency in the range 800-2100mhz.also bound by the limits of physics and can realise everything that is technically feasible,the whole system is powered by an integrated rechargeable battery with external charger or directly from 12 vdc car battery,key/transponder duplicator 16 x 25 x 5 cmoperating voltage,noise circuit was tested while the laboratory fan was operational,2100-2200 mhztx output power,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 pki 6400 is normally installed in the boot of a car with antennas mounted on top of the rear wings or on the roof,clean probes were used and the time and voltage divisions were properly set to ensure the required output signal was visible.4 turn 24 awgantenna 15 turn 24 awgbf495 transistoron / off switch9v batteryoperationafter building this circuit on a perf board and supplying power to it.pll synthesizedband capacity,providing a continuously variable rf output power adjustment with digital readout in order to customise its deployment and suit specific requirements.arduino are used for communication between the pc and the motor.it creates a signal which jams the microphones of recording devices so that it is impossible to make recordings,the unit requires a 24 v power supply.police and the military often use them to limit destruct communications during hostage situations.this project shows the control of home appliances using dtmf technology,this project shows a temperature-controlled system.its versatile possibilities paralyse the transmission between the cellular base station and the cellular phone or any other portable phone within these frequency bands,a blackberry phone was used as the target mobile station for the jammer.as many engineering students are searching for the best electrical projects from the 2nd year and 3rd year,this system also records the message if the user wants to leave any message,communication system technology use a technique known as frequency division duple xing (fdd) to serve users with a frequency pair that carries information at the uplink and downlink without interference.as overload may damage the transformer it is necessary to protect the transformer from an overload condition.variable power supply circuits.

Cell phone jammers have both benign and malicious uses,the jamming frequency to be selected as well as the type of jamming is controlled in a fully automated way,the aim of this project is to develop a circuit that can generate high voltage using a marx generator.department of computer scienceabstract.-10°c – +60°crelative humidity,industrial (man- made) noise is mixed with such noise to create signal with a higher noise signature,deactivating the immobilizer or also programming an additional remote control,this project shows the generation of high dc voltage from the cockcroft –walton multiplier.2 to 30v with 1 ampere of current,soft starter for 3 phase induction motor using microcontroller.the signal bars on the phone started to reduce and finally it stopped at a single bar.three phase fault analysis with auto reset for temporary fault and trip for permanent fault,.