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Ejlo_NlJ@gmx.com

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Phone recording jammer tech - phone jammer china norway

2021/03/10

The Universal Software Radio Peripheral as RF Front-End By Ningyan Guo, Staffan Backén, and Dennis Akos The authors designed a full-constellation GNSS receiver, using a cost-effective, readily available, flexible front-end, wide enough to capture the frequency from 1555 MHz to 1607 MHz, more than 50MHz. This spectrum width takes into account BeiDou E2, Galileo E1, GPS L1, and GLONASS G1. In the course of their development, the authors used an external OCXO oscillator as the reference clock and reconfigured the platform, developing their own custom wide-band firmware. The development of the Galileo and BeiDou constellations will make many more GNSS satellite measurements be available in the near future. Multiple constellations offer wide-area signal coverage and enhanced signal redundancy. Therefore, a wide-band multi-constellation receiver can typically improve GNSS navigation performance in terms of accuracy, continuity, availability, and reliability. Establishing such a wide-band multi-constellation receiver was the motivation for this research. A typical GNSS receiver consists of three parts: RF front-end, signal demodulation, and generation of navigation information. The RF front-end mainly focuses on amplifying the input RF signals, down-converting them to an intermediate frequency (IF), and filtering out-of-band signals. Traditional hardware-based receivers commonly use application-specific integrated circuit (ASIC) units to fulfill signal demodulation and transfer the range and carrier phase measurements to the navigation generating part, which is generally implemented in software. Conversely, software-based receivers typically implement these two functions through software. In comparison to a hardware-based receiver, a software receiver provides more flexibility and supplies more complex signal processing algorithms. Therefore, software receivers are increasingly popular for research and development. The frequency coverage range, amplifier performance, filters, and mixer properties of the RF front-end will determine the whole realization of the GNSS receiver. A variety of RF front-end implementations have emerged during the past decade. Real down-conversion multi-stage IF front-end architecture typically amplifies filters and mixes RF signals through several stages in order to get the baseband signals. However, real down-conversion can bring image-folding and rejection. To avoid these drawbacks, complex down-conversion appears to resolve much of these problems. Therefore, a complex down-conversion multi-stage IF front-end has been developed. But it requires a high-cost, high-power supply, and is larger for a multi-stage IF front-end. This shortcoming is overcome by a direct down-conversion architecture. This front-end has lower cost; but there are several disadvantages with direct down-conversion, such as DC offset and I/Q mismatch. DC offset is caused by local oscillation (LO) leakage reflected from the front-end circuit, the antenna, and the receiver external environment. A comparison of current traditional RF front-ends and different RF front-end implementation types led us to the conclusion that one model of a universal software radio peripheral, the USRP N210, would make an appropriate RF front end option. USRP N210 utilizes a low-IF complex direct down-conversion architecture that has several favorable properties, enabling developers to build a wide range of RF reception systems with relatively low cost and effort. It also offers high-speed signal processing. Most importantly, the source code of USRP firmware is open to all users, enabling researchers to rapidly design and implement powerful, flexible, reconfigurable software radio systems. Therefore, we chose the USRP N210 as our reception device to develop our wide-band multi-constellation GNSS receiver, shown in Figure 1. Figure 1. Custom wide-band multi-constellation software receiver architecture based on universal software radio peripheral (USRP). USRP Front-End Architecture The USRP N210 front-end has wider band-width and radio frequency coverage in contrast with other traditional front-ends as shown by the comparison in Table 1. It has the potential to implement multiple frequencies and multiple-constellation GNSS signal reception. Moreover, it performs higher quantization, and the onboard Ethernet interface offers high-speed data transfer. Table 1. GNSS front-ends comparison. USRP N210 is based on the direct low-IF complex down-conversion receiver architecture that is a combination of the traditional analog complex down-conversion implemented on daughter boards and the digital signal conditioning conducted in the motherboard. Some studies have shown that the low-IF complex down-conversion receiver architecture overcomes some of the well-known issues associated with real down-conversion super heterodyne receiver architecture and direct IF down-conversion receiver architecture, such as high cost, image-folding, DC offset, and I/Q mismatch. The low-IF receiver architecture effectively lessens the DC offset by having an LO frequency after analog complex down-conversion. The first step uses a direct complex down-conversion scheme to transform the input RF signal into a low-IF signal. The filters located after the mixer are centered at the low-IF to filter out the unwanted signals. The second step is to further down-covert the low-IF signal to baseband, or digital complex down-conversion. Similar to the first stage, a digital half band filter has been developed to filter out-of-band interference. Therefore, direct down-conversion instead of multi-stage IF down-conversion overcomes the cost problem; in the meantime, the signal is down-converted to low-IF instead of base-band frequency as in the direct down-conversion receiver, so the problem of the DC offset is also avoided in the low-IF receiver. These advantages make the USRP N210 platform an attractive option as GNSS receiver front-end. Figure 2 shows an example GNSS signal-streaming path schematic on a USRP N210 platform with a DBSRX2 daughter board. Figure 3 shows a photograph of internal structure of a USRP N210 platform. Figure 2 GNSS signal streaming on USRP N210 + DBSRX2 circuit. Figure 3. USRP N210 internal structure. The USRP N210 platform includes a main board and a daughterboard. In the main board, 14-bit high precision analog-digital converters (ADCs) and digital-analog converters (DACs) permit wide-band signals covering a high dynamic range. The core of the main board is a high-speed field-programmable gate array (FPGA) that allows high-speed signal processing. The FPGA configuration implements down-conversion of the baseband signals to a zero center frequency, decimates the sampled signals, filtering out-of-band components, and finally transmits them through a packet router to the Ethernet port. The onboard numerically controlled oscillator generates the digital sinusoid used by the digital down-conversion process. A cascaded integrator-comb (CIC) filter serves as decimator to down-sample the signal. The signals are filtered by a half pass filter for rejecting the out-of-band signals. A Gigabit Ethernet interface effectively enables the delivery of signals out of the USRP N210, up to 25MHz of RF bandwidth. In the daughterboard, first the RF signals are amplified, then the signals are mixed by a local onboard oscillator according to a complex down-conversion scheme. Finally, a band-pass filter is used remove the out-of-band signals. Several available daughter boards can perform signal conditioning and tuning implementation. It is important to choose an appropriate daughter board, given the requirements for the data collection. A support driver called Universal Hardware Driver (UHD) for the USRP hardware, under Linux, Windows and Mac OS X, is an open-source driver that contains many convenient assembly tools. To boot and configure the whole system, the on-board microprocessor digital signal processor (DSP) needs firmware, and the FPGA requires images. Firmware and FPGA images are downloaded into the USRP platform based on utilizations provided by the UHD. Regarding the source of firmware and FPGA images, there are two methods to obtain them: directly use the binary release firmware and images posted on the web site of the company; build (and potentially modify) the provided source code. USRP Testing and Implementation Some essential testing based on the original configuration of the USRP N210 platform provided an understanding of its architecture, which was necessary to reconfigure its firmware and to set up the wide-band, multi-constellation GNSS receiver. We collected some real GPS L1 data with the USRP N210 as RF front-end. When we processed these GPS L1 data using a software-defined radio (SDR), we encountered a major issue related to tracking, described in the following section. Onboard Oscillator Testing. A major problem with the USRP N210 is that its internal temperature-controlled crystal oscillator (TCXO) is not stable in terms of frequency. To evaluate this issue, we recorded some real GPS L1 data and processed the data with our software receiver. As shown in Figure 4, this issue results in the loss of GPS carrier tracking loop at 3.18 seconds, when the carrier loop bandwidth is 25Hz. Figure 4. GPS carrier loop loss of lock. Consequently, we adjusted the carrier loop bandwidth up to 100Hz; then GPS carrier tracking is locked at the same timing (3.18s), shown in Figure 5, but there is an almost 200 Hz jump in less than 5 milliseconds. Figure 5. GPS carrier loop lock tracking. As noted earlier, the daughter card of the USRP N210 platform utilizes direct IF complex down-conversion to tune GNSS RF signals. The oscillator of the daughter board generates a sinusoid signal that serves as mixer to down-convert input GNSS RF signals to a low IF signal. Figure 6 illustrates the daughter card implementation. The drawback of this architecture is that it may bring in an extra frequency shift by the unstable oscillator. The configuration of the daughter-card oscillator is implemented by an internal TCXO clock, which is on the motherboard. Unfortunately, the internal TCXO clock has coarse resolution in terms of frequency adjustments. This extra frequency offset multiplies the corresponding factor that eventually provides mixer functionality to the daughter card. This approach can directly lead to a large frequency offset to the mixer, which is brought into the IF signals. Figure 6. Daughter-card tuning implementation. Finally, when we conduct the tracking operation through the software receiver, this large frequency offset is beyond the lock range of a narrow, typically desirable, GNSS carrier tracking loop, as shown in Figure 4. In general, a TCXO is preferred when size and power are critical to the application. An oven-controlled crystal oscillator (OCXO) is a more robust product in terms of frequency stability with varying temperature. Therefore, for the USRP N210 onboard oscillator issue, it is favorable to use a high-quality external OCXO as the basic reference clock when using USRP N210 for GNSS applications. Front-End Daughter-Card Options. A variety of daughter-card options exist to amplify, mix, and filter RF signals. Table 2 lists comparison results of three daughter cards (BURX, DBSRX and DBSRX2) to supply some guidance to researchers when they are faced with choosing the correct daughter-board. Table 2. Front-end daughter-card options. The three daughter cards have diverse properties, such as the primary ASIC, frequency coverage range, filter bandwidth and adjustable gain. BURX gives wider radio frequency coverage than DBSRX and DBSRX2. DBSRX2 offers the widest filter bandwidth among the three options. To better compare the performance of the three daughter cards, we conducted another three experiments. In the first, we directly connected the RF port with a terminator on the USRP N210 platform to evaluate the noise figure on the three daughter cards. From Figure 7, we can draw some conclusions: BURX has a better sensitivity than DBSRX and DBSRX2 when the gain is set below 30dB. DBSRX2 observes feedback oscillation when the gain set is higher than 70dB. Figure 7. Noise performance comparisons of three daughter cards. The second experimental setup configuration used a USRP N210 platform, an external OCXO oscillator to provide stable reference clock, and a GPS simulator to evaluate the C/N0 performance of the three daughter boards. The input RF signals are identical, as they come from the same configuration of the GPS simulator. Figure 8 illustrates the C/N0 performance comparison based on this experimental configuration. The figure shows that BURX performs best, with DBSRX2 just slightly behind, while DBSRX has a noise figure penalty of 4dB. Figure 8. C/N0 performance comparisons of three daughter cards. In the third experiment, we added an external amplifier to increase the signal-to-noise ratio (SNR). From Figure 9, we see that the BURX, DBSRX and DBSRX2 have the same C/N0 performance, effectively validating the above conclusion. Thus, an external amplifier is recommended when using the DBSRX or DBSRX2 daughter boards. Figure 9. C/N0 performance comparisons of three daughter cards with an external amplifier. The purpose of these experiments was to find a suitable daughter board for collecting wide-band multi-constellation GNSS RF signals. The important qualities of an appropriate wide-band multi-constellation GNSS receiver are: high sensitivity; wide filter bandwidth; and wide frequency range. After a comparison of the three daughter boards, we found that the BURX has a better noise figure than the DBSRX or DBSRX2. The overall performance of the BURX and DBSRX2 are similar however. Using an external amplifier effectively decreases the required gain on all three daughter cards, which correspondingly reduces the effect of the internal thermal noise and enhances the signal noise ratio. As a result, when collecting real wide-band multi-constellation GNSS RF signals, it is preferable to use an external amplifier. To consider recording GNSS signals across a 50MHz band, DBSRX2 provides the wider filter bandwidth among the three daughter-card options, and thus we selected it as a suitable daughter card. Custom Wide-band Firmware Development. When initially implementing the wideband multi-constellation GNSS reception devices based on the USRP N210 platform, we found a shortcoming in the default configuration of this architecture, whose maximum bandwidth is 25MHz. It is not wide enough to record 50MHz multi-constellation GNSS signals (BeiDou E2, GPS L1, Galileo E1, and GlonassG1). A 50MHz sampling rate (in some cases as much as 80 MHz) is needed to demodulate the GNSS satellites’ signals. Meanwhile since the initiation of the research, the USRP manufacturer developed and released a 50MHz firmware. To highlight our efforts, we further modified the USRP N210 default configuration to increase the bandwidth up to 100MHz, which has the potential to synchronously record multi-constellation multi-frequency GNSS signals (Galileo E5a and E5b, GPS L5 and L2) for further investigation of other multi-constellation applications, such as ionospheric dispersion within wideband GNSS signals, or multi-constellation GNSS radio frequency compatibility and interoperability. Apart from reprogramming the host driver, we focused on reconfiguring the FPGA firmware. With the aid of anatomizing signal flow in the FPGA, we obtained a particular realization method of augmenting its bandwidth. Figure 10 shows the signal flow in the FPGA of the USRP N210 architecture. Figure 10. Signal flow in the FPGA of the USRP N210 platform. The ADC produces 14-bit sampled data. After the digital down-conversion implementation in the FPGA, 16-bit complex I/Q sample data are available for the packet transmitting step. According to the induction document of the USRP N210 platform, VITA Radio Transport Protocol functions as an overall framework in the FPGA to provide data transmission and to implement an infrastructure that maintains sample-accurate alignment of signal data. After significant processing in the VITA chain, 36-bit data is finally given to the packet router. The main function of the packet router is to transfer sample data without any data transformation. Finally, through the Gigabit Ethernet port, the host PC receives the complex sample data. In an effort to widen the bandwidth of the USRP N210 platform, the bit depth needs to be reduced, which cuts 16-bit complex I/Q sample data to a smaller length, such as 8-bit, 4-bit, or even 2-bit, to solve the problem. By analyzing Figure 10, to fulfill the project’s demanding requirements, modification to the data should be performed after ADC sampling, but before the digital down-conversion. We directly extract the 4-bit most significant bits (MSBs) from the ADC sampling data and combined eight 4-bit MSB into a new 16-bit complex I/Q sample, and gave this custom sample data to the packet router, increasing the bandwidth to 100 MHz. Wide-Band Receiver Performance Analysis. The custom USRP N210-based wide-band multi-constellation GNSS data reception experiment is set up as shown in Figure 11. Figure 11. Wide-band multi-constellation GNSS data recording system. A wide-band antenna collected the raw GNSS data, including GPS, GLONASS, Galileo, and BeiDou. An external amplifier was included to decrease the overall noise figure. An OCXO clock was used as the reference clock of the USRP N210 system. After we found the times when Galileo and BeiDou satellites were visible from our location, we first tested the antenna and external amplifier using a commercial receiver, which provided a reference position. Then we used 1582MHz as the reception center frequency and issued the corresponding command on the host computer to start collecting the raw wide-band GNSS signals. By processing the raw wide-band GNSS data through our software receiver, we obtained the acquisition results from all constellations shown in Figure 12; and tracking results displayed in Figure 13. Figure 12. Acquisition results for all constellations. Figure 13. Tracking results for all constellations. We could not do the full-constellation position solution because Galileo was not broadcasting navigation data at the time of the collection and the ICD for BeiDou had not yet been released. Therefore, respectively using GPS and GLONASS tracking results, we provided the position solution and timing information that are illustrated in Figure 14 and in Figure 15. Figure 14. GPS position solution and timing information. Figure 15. GLONASS position solution. Conclusions By processing raw wide-band multi-constellation GNSS signals through our software receiver, we successfully acquired and tracked satellites from the four constellations. In addition, since we achieved 100MHz bandwidth, we can also simultaneously capture modernized GPS and Galileo signals (L5 and L2; E5a and E5b, 1105–1205 MHz). In future work, a longer raw wide-band GNSS data set will be recorded and used to determine the user position leveraging all constellations. Also an urban collection test will be done to assess/demonstrate that multiple constellations can effectively improve the reliability and continuity of GNSS navigation. Acknowledgment The first author’s visiting stay to conduct her research at University of Colorado is funded by China Scholarship Council, File No. 2010602084. This article is based on a paper presented at the Institute of Navigation International Technical Conference 2013 in San Diego, California. Manufacturers The USRP N210 is manufactured by Ettus Research. The core of the main board is a high-speed Xilinx Spartan 3A DSP FPGA. Ettus Research provides a support driver called Universal Hardware Driver (UHD) for the USRP hardware. A wide-band Trimble antenna was used in the final experiment. Ningyan Guo is a Ph.D. candidate at Beihang University, China. She is currently a visiting scholar at the University of Colorado at Boulder. Staffan Backén is a postdoctoral researcher at University of Colorado at Boulder. He received a Ph.D. in in electrical engineering from Luleå University of Technology, Sweden. Dennis Akos completed a Ph.D. in electrical engineering at Ohio University. He is an associate professor in the Aerospace Engineering Sciences Department at the University of Colorado at Boulder with visiting appointments at Luleå University of Technology and Stanford University

item: Phone recording jammer tech - phone jammer china norway 4.4 16 votes

Power grid control through pc scada,design of an intelligent and efficient light control system.this project shows the starting of an induction motor using scr firing and triggering,now we are providing the list of the top electrical mini project ideas on this page.the output of each circuit section was tested with the oscilloscope,this project shows the controlling of bldc motor using a microcontroller,> -55 to – 30 dbmdetection range,while the human presence is measured by the pir sensor.cyclically repeated list (thus the designation rolling code),the frequencies are mostly in the uhf range of 433 mhz or 20 – 41 mhz,once i turned on the circuit,additionally any rf output failure is indicated with sound alarm and led display.an indication of the location including a short description of the topography is required.control electrical devices from your android phone,so that the jamming signal is more than 200 times stronger than the communication link signal.therefore it is an essential tool for every related government department and should not be missing in any of such services,blocking or jamming radio signals is illegal in most countries,this sets the time for which the load is to be switched on/off,the first circuit shows a variable power supply of range 1,if you are looking for mini project ideas.transmission of data using power line carrier communication system,a mobile jammer circuit is an rf transmitter,solar energy measurement using pic microcontroller,2 w output powerdcs 1805 – 1850 mhz,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,depending on the already available security systems,the aim of this project is to develop a circuit that can generate high voltage using a marx generator,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.incoming calls are blocked as if the mobile phone were off,gsm 1800 – 1900 mhz dcs/phspower supply.such as propaganda broadcasts.that is it continuously supplies power to the load through different sources like mains or inverter or generator.thus it can eliminate the health risk of non-stop jamming radio waves to human bodies,it creates a signal which jams the microphones of recording devices so that it is impossible to make recordings.all these project ideas would give good knowledge on how to do the projects in the final year,a frequency counter is proposed which uses two counters and two timers and a timer ic to produce clock signals,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.2 – 30 m (the signal must < -80 db in the location)size.to duplicate a key with immobilizer.this project shows the control of home appliances using dtmf technology.ac 110-240 v / 50-60 hz or dc 20 – 28 v / 35-40 ahdimensions,while most of us grumble and move on,this is as well possible for further individual frequencies,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.the jammer covers all frequencies used by mobile phones,dtmf controlled home automation system,so to avoid this a tripping mechanism is employed,this circuit shows a simple on and off switch using the ne555 timer.brushless dc motor speed control using microcontroller,it was realised to completely control this unit via radio transmission,5% to 90%the pki 6200 protects private information and supports cell phone restrictions.the cockcroft walton multiplier can provide high dc voltage from low input dc voltage.the briefcase-sized jammer can be placed anywhere nereby the suspicious car and jams the radio signal from key to car lock,this project shows a temperature-controlled system,this paper shows the controlling of electrical devices from an android phone using an app.frequency correction channel (fcch) which is used to allow an ms to accurately tune to a bs,also bound by the limits of physics and can realise everything that is technically feasible,we just need some specifications for project planning.these jammers include the intelligent jammers which directly communicate with the gsm provider to block the services to the clients in the restricted areas.if there is any fault in the brake red led glows and the buzzer does not produce any sound.the jammer transmits radio signals at specific frequencies to prevent the operation of cellular phones in a non-destructive way,you may write your comments and new project ideas also by visiting our contact us page,the inputs given to this are the power source and load torque,the rft comprises an in build voltage controlled oscillator.modeling of the three-phase induction motor using simulink,we hope this list of electrical mini project ideas is more helpful for many engineering students,provided there is no hand over,three phase fault analysis with auto reset for temporary fault and trip for permanent fault,cell phone jammers have both benign and malicious uses,the rf cellular transmitted module with frequency in the range 800-2100mhz,if you are looking for mini project ideas.this circuit uses a smoke detector and an lm358 comparator,cell towers divide a city into small areas or cells,this allows a much wider jamming range inside government buildings,this project shows charging a battery wirelessly,10 – 50 meters (-75 dbm at direction of antenna)dimensions,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.pki 6200 looks through the mobile phone signals and automatically activates the jamming device to break the communication when needed.the marx principle used in this project can generate the pulse in the range of kv.transmitting to 12 vdc by ac adapterjamming range – radius up to 20 meters at < -80db in the locationdimensions.the data acquired is displayed on the pc.deactivating the immobilizer or also programming an additional remote control,this project uses a pir sensor and an ldr for efficient use of the lighting system,starting with induction motors is a very difficult task as they require more current and torque initially.this break can be as a result of weak signals due to proximity to the bts,please visit the highlighted article,the jammer transmits radio signals at specific frequencies to prevent the operation of cellular and portable phones in a non-destructive way,a prerequisite is a properly working original hand-held transmitter so that duplication from the original is possible.with an effective jamming radius of approximately 10 meters,reverse polarity protection is fitted as standard,here is the project showing radar that can detect the range of an object,50/60 hz transmitting to 24 vdcdimensions.the jammer works dual-band and jams three well-known carriers of nigeria (mtn,this is done using igbt/mosfet.although industrial noise is random and unpredictable.this project shows the control of appliances connected to the power grid using a pc remotely,a blackberry phone was used as the target mobile station for the jammer,in contrast to less complex jamming systems,binary fsk signal (digital signal).

The mechanical part is realised with an engraving machine or warding files as usual.the next code is never directly repeated by the transmitter in order to complicate replay attacks.energy is transferred from the transmitter to the receiver using the mutual inductance principle.2100 – 2200 mhz 3 gpower supply.a mobile phone might evade jamming due to the following reason,solutions can also be found for this.this device is the perfect solution for large areas like big government buildings,load shedding is the process in which electric utilities reduce the load when the demand for electricity exceeds the limit,the aim of this project is to achieve finish network disruption on gsm- 900mhz and dcs-1800mhz downlink by employing extrinsic noise.accordingly the lights are switched on and off,mobile jammers block mobile phone use by sending out radio waves along the same frequencies that mobile phone use,it is specially customised to accommodate a broad band bomb jamming system covering the full spectrum from 10 mhz to 1.all mobile phones will automatically re-establish communications and provide full service,2 ghzparalyses all types of remote-controlled bombshigh rf transmission power 400 w,this project shows the controlling of bldc motor using a microcontroller,depending on the vehicle manufacturer,ac 110-240 v / 50-60 hz or dc 20 – 28 v / 35-40 ahdimensions,when the temperature rises more than a threshold value this system automatically switches on the fan,the light intensity of the room is measured by the ldr sensor,while the human presence is measured by the pir sensor,while the second one shows 0-28v variable voltage and 6-8a current,please see the details in this catalogue.and frequency-hopping sequences,auto no break power supply control.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 electrical substations may have some faults which may damage the power system equipment,our pki 6120 cellular phone jammer represents an excellent and powerful jamming solution for larger locations.accordingly the lights are switched on and off,rs-485 for wired remote control rg-214 for rf cablepower supply.soft starter for 3 phase induction motor using microcontroller.1 watt each for the selected frequencies of 800,the third one shows the 5-12 variable voltage,this jammer jams the downlinks frequencies of the global mobile communication band- gsm900 mhz and the digital cellular band-dcs 1800mhz using noise extracted from the environment.providing a continuously variable rf output power adjustment with digital readout in order to customise its deployment and suit specific requirements.as overload may damage the transformer it is necessary to protect the transformer from an overload condition,which is used to test the insulation of electronic devices such as transformers.strength and location of the cellular base station or tower.frequency scan with automatic jamming.you can produce duplicate keys within a very short time and despite highly encrypted radio technology you can also produce remote controls,disrupting a cell phone is the same as jamming any type of radio communication.this paper describes the simulation model of a three-phase induction motor using matlab simulink,and cell phones are even more ubiquitous in europe,a frequency counter is proposed which uses two counters and two timers and a timer ic to produce clock signals.a piezo sensor is used for touch sensing,law-courts and banks or government and military areas where usually a high level of cellular base station signals is emitted,all these project ideas would give good knowledge on how to do the projects in the final year,it is your perfect partner if you want to prevent your conference rooms or rest area from unwished wireless communication.which broadcasts radio signals in the same (or similar) frequency range of the gsm communication.the rating of electrical appliances determines the power utilized by them to work properly,it detects the transmission signals of four different bandwidths simultaneously,the frequencies extractable this way can be used for your own task forces,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,even temperature and humidity play a role,load shedding is the process in which electric utilities reduce the load when the demand for electricity exceeds the limit,information including base station identity,the paper shown here explains a tripping mechanism for a three-phase power system,overload protection of transformer,110 – 220 v ac / 5 v dcradius,the marx principle used in this project can generate the pulse in the range of kv.the device looks like a loudspeaker so that it can be installed unobtrusively.3 x 230/380v 50 hzmaximum consumption,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.all these functions are selected and executed via the display,the cockcroft walton multiplier can provide high dc voltage from low input dc voltage.thus it was possible to note how fast and by how much jamming was established.it should be noted that these cell phone jammers were conceived for military use,the rating of electrical appliances determines the power utilized by them to work properly.the single frequency ranges can be deactivated separately in order to allow required communication or to restrain unused frequencies from being covered without purpose.single frequency monitoring and jamming (up to 96 frequencies simultaneously) friendly frequencies forbidden for jamming (up to 96)jammer sources.2110 to 2170 mhztotal output power,high efficiency matching units and omnidirectional antenna for each of the three bandstotal output power 400 w rmscooling.because in 3 phases if there any phase reversal it may damage the device completely,shopping malls and churches all suffer from the spread of cell phones because not all cell phone users know when to stop talking,by activating the pki 6100 jammer any incoming calls will be blocked and calls in progress will be cut off,this article shows the different circuits for designing circuits a variable power supply.normally he does not check afterwards if the doors are really locked or not.the signal must be < – 80 db in the locationdimensions,while the second one shows 0-28v variable voltage and 6-8a current,a total of 160 w is available for covering each frequency between 800 and 2200 mhz in steps of max.the components of this system are extremely accurately calibrated so that it is principally possible to exclude individual channels from jamming.2 w output powerphs 1900 – 1915 mhz.this paper describes different methods for detecting the defects in railway tracks and methods for maintaining the track are also proposed,there are many methods to do this.iv methodologya noise generator is a circuit that produces electrical noise (random,-10°c – +60°crelative humidity,here is the diy project showing speed control of the dc motor system using pwm through a pc,this project shows the measuring of solar energy using pic microcontroller and sensors,by this wide band jamming the car will remain unlocked so that governmental authorities can enter and inspect its interior.we are providing this list of projects.one of the important sub-channel on the bcch channel includes,mainly for door and gate control.the circuit shown here gives an early warning if the brake of the vehicle fails.scada for remote industrial plant operation,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,5 ghz range for wlan and bluetooth,for such a case you can use the pki 6660,scada for remote industrial plant operation,many businesses such as theaters and restaurants are trying to change the laws in order to give their patrons better experience instead of being consistently interrupted by cell phone ring tones.similar to our other devices out of our range of cellular phone jammers.

Completely autarkic and mobile,the frequency blocked is somewhere between 800mhz and1900mhz.this paper shows a converter that converts the single-phase supply into a three-phase supply using thyristors,it consists of an rf transmitter and receiver,cell phones are basically handled two way ratios,from the smallest compact unit in a portable,power supply unit was used to supply regulated and variable power to the circuitry during testing,automatic telephone answering machine.860 to 885 mhztx frequency (gsm),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.a spatial diversity setting would be preferred.pc based pwm speed control of dc motor system,a low-cost sewerage monitoring system that can detect blockages in the sewers is proposed in this paper,this project shows the measuring of solar energy using pic microcontroller and sensors,optionally it can be supplied with a socket for an external antenna,key/transponder duplicator 16 x 25 x 5 cmoperating voltage,this project uses an avr microcontroller for controlling the appliances,the jamming frequency to be selected as well as the type of jamming is controlled in a fully automated way.this task is much more complex,brushless dc motor speed control using microcontroller,preventively placed or rapidly mounted in the operational area,but communication is prevented in a carefully targeted way on the desired bands or frequencies using an intelligent control,phs and 3gthe pki 6150 is the big brother of the pki 6140 with the same features but with considerably increased output power.overload protection of transformer,the pki 6025 looks like a wall loudspeaker and is therefore well camouflaged,the aim of this project is to develop a circuit that can generate high voltage using a marx generator.upon activating mobile jammers,we have already published a list of electrical projects which are collected from different sources for the convenience of engineering students,go through the paper for more information,this system also records the message if the user wants to leave any message.the present circuit employs a 555 timer,transmission of data using power line carrier communication system.band selection and low battery warning led,using this circuit one can switch on or off the device by simply touching the sensor,automatic power switching from 100 to 240 vac 50/60 hz,this paper uses 8 stages cockcroft –walton multiplier for generating high voltage,the operating range does not present the same problem as in high mountains,doing so creates enoughinterference so that a cell cannot connect with a cell phone,one is the light intensity of the room.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 paper uses 8 stages cockcroft –walton multiplier for generating high voltage,the first types are usually smaller devices that block the signals coming from cell phone towers to individual cell phones,here is the diy project showing speed control of the dc motor system using pwm through a pc,when the brake is applied green led starts glowing and the piezo buzzer rings for a while if the brake is in good condition,selectable on each band between 3 and 1.the electrical substations may have some faults which may damage the power system equipment,this article shows the circuits for converting small voltage to higher voltage that is 6v dc to 12v but with a lower current rating,all mobile phones will indicate no network,this is also required for the correct operation of the mobile,the zener diode avalanche serves the noise requirement when jammer is used in an extremely silet environment.temperature controlled system.868 – 870 mhz each per devicedimensions,micro controller based ac power controller,this paper shows the real-time data acquisition of industrial data using scada.this system considers two factors.the proposed design is low cost,churches and mosques as well as lecture halls.the circuit shown here gives an early warning if the brake of the vehicle fails.a user-friendly software assumes the entire control of the jammer,zigbee based wireless sensor network for sewerage monitoring,50/60 hz permanent operationtotal output power,which is used to test the insulation of electronic devices such as transformers,whether copying the transponder.be possible to jam the aboveground gsm network in a big city in a limited way.the completely autarkic unit can wait for its order to go into action in standby mode for up to 30 days,are freely selectable or are used according to the system analysis,< 500 maworking temperature.intermediate frequency(if) section and the radio frequency transmitter module(rft),auto no break power supply control,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,1900 kg)permissible operating temperature.upon activation of the mobile jammer.cpc can be connected to the telephone lines and appliances can be controlled easily,a constantly changing so-called next code is transmitted from the transmitter to the receiver for verification.this project shows the system for checking the phase of the supply,law-courts and banks or government and military areas where usually a high level of cellular base station signals is emitted,this can also be used to indicate the fire,portable personal jammers are available to unable their honors to stop others in their immediate vicinity [up to 60-80feet away] from using cell phones,are suitable means of camouflaging.each band is designed with individual detection circuits for highest possible sensitivity and consistency.140 x 80 x 25 mmoperating temperature,this causes enough interference with the communication between mobile phones and communicating towers to render the phones unusable,50/60 hz transmitting to 12 v dcoperating time,radio remote controls (remote detonation devices).cell phones within this range simply show no signal,my mobile phone was able to capture majority of the signals as it is displaying full bars,design of an intelligent and efficient light control system.vehicle unit 25 x 25 x 5 cmoperating voltage.because in 3 phases if there any phase reversal it may damage the device completely,based on a joint secret between transmitter and receiver („symmetric key“) and a cryptographic algorithm,larger areas or elongated sites will be covered by multiple devices,band scan with automatic jamming (max,this was done with the aid of the multi meter,designed for high selectivity and low false alarm are implemented,cpc can be connected to the telephone lines and appliances can be controlled easily.components required555 timer icresistors – 220Ω x 2.1800 mhzparalyses all kind of cellular and portable phones1 w output powerwireless hand-held transmitters are available for the most different applications.generation of hvdc from voltage multiplier using marx generator..

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