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Gps tracker signal jammer yellow , vehicle gps signal jammer instructions

Permanent Link to Assured PNT for Our Future: PTA

Actions Necessary to Reduce Vulnerability and Ensure Availability By Brad Parkinson (From the 25th Anniversary GNSS History Special Supplement) Introduction Brad Parkinson About 40 years ago, we had a vision for positioning, navigation, and timing (PNT). That vision was more than successful, and became known as GPS. In some respects we have been almost too successful: PNT is frequently taken for granted. PNT, in the form of GPS, has become a powerful worldwide enabler for productivity and for safety. Estimated yearly value runs to many tens of billions of dollars.  For several years, I have been concerned about comments that denigrate GPS because the signal strength is relatively weak. The speakers have gone on to say it can be completely replaced with inertial or other techniques. Recently, comments by government officials further energized me to look at the full picture. What can we do to reduce the vulnerability and ensure that the expectations of the users are going to be met? I summarize my solution as the PTA program and will elaborate in this article. At a top level, the term PTA means: Protect, Toughen, and Augment GPS to assure PNT. Note I say PNT, not GPS. The central issue is assuring access of PNT to the user, not the source of the information. I strongly believe that PTA is both achievable and absolutely necessary. Protecting PNT is particularly important to Europeans as they are just about to launch their fledgling Galileo system. Speeches and travel only reach a limited number. When GPS World invited me to write a piece for the magazine’s 25th anniversary issue, it seemed an ideal opportunity to expand knowledge of the PTA program. The following is an edited form of a talk I have given a number of times, most recently at the European Navigation Conference in Rotterdam in April 2014. GNSS initiatives and the GNSS community are growing rapidly, and certainly we are very enthusiastic about the progress of Galileo. But some places in the U.S. community are saying, “Well, this GPS band is underutilized; devoting all that bandwidth to a single system is not prudent.” I beg to differ with that view. If you look at the separate signals in the L1 band around the world, by the year 2023 they will grow to be well more than 400 individual signals. Those signals service over 2 billion users, from emergency service providers to precision agriculture to crustal monitoring and many, many more. I have an entirely separate talk on “GPS for Humanity,” but that is not our subject today.  Calling the GPS frequency band “underutilized” simply points out ignorance, even among our supporters. For example, we say PNT to emphasize that GNSS provides four dimensions. Certainly, timing is the forgotten fourth dimension of GPS, and even our politician friends rarely understand the importance of this aspect. Yet we know that highly accurate timing, supplied by GPS, is absolutely critical for power distribution, for telecommunications, and for the financial sector.  It is instructive to summarize the penetration of the PNT “Stealth Utility” into the fabric of our society. Market Size. Overall, GPS has more than 2 billion users worldwide. This represents a very diverse user group; we providers are continually seeing new and innovative ways to use GPS.  Figure 1, for which I am indebted to Frank van Diggelen, gives an estimate of the number of receivers currently fielded. Notice the number of military receivers: less than half a million. The gray bar depicts the industrial uses such as survey and machine control, which come in at about 4.5 million; these tend to be extremely high enhancers of industrial productivity.  Figure 1. GNSS market size, 2012. We have to change the chart scale to depict bigger market segments. For example, recreation, automotive, and computing are shown on the lower half of the chart. In fact, mobile phones will still not fit on the chart. Attesting to the size of the estimated mobile phone base: one company alone will produce more than 900 million GPS-equipped smartphones this year. The pie diagram shows the dominance of mobile devices, but much higher productivity gains come from high-precision devices whose impact is very disproportionate to numbers of receivers.   We asked some economists, just what is all this worth? They looked at a subset of all the industries and concluded that GPS has a positive net effect to the tune of at least $32 billion annually. They had an expanded study that suggested about $90 billion annually. So, for those who question the value of GPS, the answer is that the net yearly returns to our national investment are more than 1000 percent. (Note: National investment is about $3 billion annually.) To ensure these enormous economic benefits of PNT, there are two fundamental needs, and we providers must assure that they are met. The first and most important need is availability.  Availability. When we say availability, it is defined in a certain way; it means that PNT is available at the application-specified accuracy. We usually measure that accuracy at the 90th percentile: only 10 percent of the time can that error be exceeded.  Integrity. The second user need is the required integrity. That means that when the user expects a specific accuracy, the system is not lying to him. Integrity assurance is very much a focus of both the International Civil Aviation Organization (ICAO) and, in the United States, the Federal Aviation Administration (FAA). In many cases they require that PNT errors not exceed specified bounds more than once in 10 billion measurements (1 x 10-7). This integrity level requires so many samples, it is virtually impossible to verify experimentally; we have not had that many airplane landings, but it can be calculated. The metric we use is how many minutes GPS is not available — unavailability — at the specified accuracy and integrity. That is more easily understood than availability that aproaches 99.9XXX percent. The usual goal is that unavailability be zero.  We have an independent assessment of how well we are doing: FAA’s Wide Area Augmentation System (WAAS). They put out a report card with a lot of numbers. GPS clearly deserves a grade of A+.  And it will get better. The U.S. government’s PNT Advisory Board, which I co-chair, recently advocated that the full navigation message be added at the new civil frequencies, the L2C and L5C signals. The Air Force has now complied, thanks to strong support from General Willie Shelton. This makes two more civil signals fully available. They currently expect 2.9 meter ranging accuracy, but by the end of the year the Air Force operators expect the same full accuracy as the rest of the signals, on the order of 0.5 meter of ranging error.  This is an outstanding picture. So What’s the Problem? A statement made by a high-level U.S. government official in my presence exemplifies the problem: “GPS is much too vulnerable. We must replace it with new inertials and chip-scale atomic clocks.”  I found this statement appalling. Unfortunately, it was a meeting where you don’t normally speak up, and I didn’t. Nonetheless, to me, that was totally wrong.  GPS indeed has a very weak signal, and it depends on having clear line-of-sight to four satellites. But in my opinion, a much better statement is what I call the PTA solution. Our goal should be to: Protect the system and the signal.  Toughen the receiver and the system.  Augment GPS as needed to ensure users’ PNT requirements are met.  The focus is ensuring positioning, navigation, and timing (PNT), not merely ensuring GPS. Fundamental Prerequisites for PNT  The first prerequisite for GPS-based PNT is a receivable, clear, and truthful (truthful implies full integrity) ranging signal. There are five main challenges to this. Too-powerful authorized signalsnearby. This aspect snuck up on our community. The FCC authorizers were about to license a powerful signal in the frequency band adjacent to GPS, drowning out any hope of receiving the GPS signal. This can be called the authorized jammer. All PNT providers must be very vigilant about this; we have seen ignorant elements of the government poised to do great harm with well-intended but destructive actions, without knowledge of the unintended consequences.  Natural Interference. This interference, the cause of delays and attenuation, is reasonably well understood, and the subject of much research, dating back to when we first defined GPS. Random events such as solar flares can potentially cause great harm.  Inadvertent Natural or Manmade Jamming. A nearby device that creates spurious, destructive emissions can be a serious problem for GPS receivers. This class tends to be manageable by well-designed receivers.  Collateral Interference. An example is a person who wants to evade tracking but is inadvertently jamming nearby GNSS receivers in addition to his own local receiver.  Deliberate Jamming or Spoofing. This is perhaps the major concern for developers and users. I will discuss this further later. There is a second major prerequisite: satellite geometry. The user who cannot see enough of the sky is called “sky-impaired.” There are two possible underlying problems:  The satellite constellation has “brown-out” because of failures or inadequate numbers; or The user is operating in a mountainous or urban area with high, local shading angles. Overcoming sky-impairment requires a denser constellation, or use of multiple GNSS.  Protect, Toughen, Augment  What can we — as developers, operators, and manufacturers — do to overcome the PNT availability challenges for our users? My solution is PTA. The good news is that quite a few of the actions I recommend are underway — in fact, many of GPS World’s readers are active participants.  I am going to examine these three PTA principles, expand on them a bit, and hopefully explain a few things that help focus on a broad solution.  Protect the System and the Signal This can be organized into seven actions: three PreActions and four ReActions. PreActions are before there is serious interference, and ReActions obviously come after interference is occurring. First, the PreActions. Protect the Spectrum. The chart in Figure 2 represents the frequency plan for the L1 band, and displays some of the sources of the 400 signals I referenced earlier. The blue star, GPS L1 C/ A, is the only fully operational and reliable signal in the world right now. The red star is the U.S. GPS military signal. You can see it has important power lobes close to the band edge. The black star is M-code, the new military signal of the United States.  Figure 2. Frequency plan for the L1 band. The Galileo power curve, which is pale green, has very significant nodes close to the band edge. Of course, the Galileo PRS (the magenta star) is right on the band edge. The imperative for these wider bandwidths is that they produce sharper correlation edges and consequently produce greater measurement precision. This leads to greater accuracy, and greater usefulness and utility for many PNT users. Reallocation of radio bands adjacent to GNSS poses a significant threat. The band edge of the proposed high-power communication signal (sometimes called broadband) appears as the black vertical line. It is obviously very close to the edges of many of the colored PNT signals. Tests conclusively demonstrated unacceptable levels of interference with L1 C/A. Consider the proposed, high-powered terrestrial signal one quarter-mile from a GPS receiver. This produces a power ratio of 5 billion (broadband) to one (GPS). To visualize that power ratio, consider Niagara Falls, which produces about a billion watts. Compared to that, GPS power is a tablespoon of water dropped from five feet, once per second (about 0.2 watts). This is the power ratio that was almost authorized with 40,000 ground-based transmitters in the U.S. At a city block away, the effect is 10 times worse. To quantify interference effects, some initial tests were run and measured broadband effects used for analysis. Cell-tower locations near Las Vegas, Nevada, approximated the broadband transmitter locations. The nearby airport, McCarran Field, has three RNAV (GPS) approaches. As expected, GPS users on the ground would be significantly jammed, but the effect on aircraft would be nine times worse than the impact on ground receivers. This is due to altitude (line of sight), geometry, and the sensitivity of aircraft receivers.  The 12 broadband transmitters around McCarran Field would jam all of the RNAV GPS approaches to all three runways. Signals of this type would effectively shut down or severely limit operations at the airport.  Signals in the GPS band will increase in the next decade as the newer GNSS become operational. The proposed, adjacent broadband is even more incompatible with these newer signals since they will be closer in frequency. Note that the whole approach was rejected, solely on the basis of L1/CA. It was not even tested against the other, more susceptible, modern signals. The worst would have been yet to come, had they been authorized to broadcast in the adjacent band.  Adjacent bands can continue to broadcast non-GNSS signals originating in space because the power levels will be comparable with the PNT spectrum. But we must be very vigilant to stop any high-power terrestrial signals from being allowed. They would become, effectively, authorized jammers. There should be no spectrum reallocation to ground transmitters until technology has been thoroughly demonstrated to solve any problems, (particularly for the high-precision users) and there is enough time to re-equip the users.  Europeans should have two other important frequency authorization concerns. First, there is a legal barrier within the United States to using Galileo signals. They have not been formally authorized. I think it is a bureaucratic glitch, but it is something we in the United States have to solve; we do want to use all GNSS signals. Stay tuned! There is another concern. A group at the Electronic Communications Committee, European Commission, recommends allowing pseudolites in the L1 GNSS band. As an experienced user of pseudolites for aircraft landing and some other applications, I believe this is a very risky idea; pseudolites can be very useful, but frequencies should be found elsewhere to avoid unexpected interference.  Stiff Legal Penalties for Interference. The second PreAction is to enact stiff legal penalties for GPS jamming, both in terms of jail time and fines. The goal is to deter the ubiquitous $33 GPS jammer that one can buy on the Internet.  On the U.S. FCC website, the agency lists the penalties for having a GPS jammer. Forfeitures range up to $16,000, and they might even put you in jail. The Australians take a much stronger view: up to five years imprisonment or $850,000 in some cases. Some people are alarmed by these heavy penalties and call them brutal. However, they are not always imposed, and if jamming and spoofing is intentional, especially where the landing of airplanes is concerned and lives are at stake, I think a strong deterrent is warranted.  Stop Jammer Manufacturing, Sales. The third pre-action is to prevent proliferation by shutting down manufacturing and web sales of jammers. What is the status? The FCC website states that manufacturers should comply with the law: stop marketing these devices in the United States and stop selling and shipping to addresses in the United States. The loophole is you apparently can manufacture these devices if you sell them outside the U.S. Now, I have a little difficulty with this. I have pointed this out to the DHS and others; hopefully, stronger action will be taken. The FCC told me in an open meeting a few months ago that they were shutting down the websites where these devices are sold. But about three weeks ago, I went online and immediately found a website that sells nine different devices to jam GPS and cellphone devices. Indeed, there were jammers, all very affordable, for jamming just about everything. More recently, the FCC assessed a multi-million dollar penalty against such a jammer manufacturer. We will see if this actually happens. I hope they accelerate these efforts. Now for the ReActions. Detect Jamming. To stop jamming, the first step is to know when it is occurring. There are a variety of ways to do this. Some devices or concepts are already on the table: for example, a Chronos CTL3510 GPS Jammer Detector, an Exelis Signal Sentry Jammer Detector, and the J911 cell phone detection and reporting of jamming, an example from NavSys. The idea behind the NavSys J911 is that all GPS-equipped smartphones have the capability to detect jamming. This does not pinpoint jammer location, but alerts authorities to the problem. Phone location can be reported to a central database for the next two actions. Pinpoint Jammer Location. Techniques range from directional antennas to time-difference-of-arrival using Fast Fourier Transforms. The latter was demonstrated for the FAA at Stanford more than 10 years ago: location pinpointed within five meters. Cell towers could implement such techniques, since they have accurate time and could run correlations. There are already commercial GPS jamming locators: something called a JLOC (NaySys Jammer Locator). The British are using similar techniques for jammer detection on some of their freeways.  Eliminate Jammer. Having pinpointed the jammer, the next step is to physically eliminate it. What is the status? At Newark Airport there is an FAA, ground-based GPS augmentation system antenna right next to the turnpike. They are part of a blind landing system. In early 2010, there was an infamous jammer interfering with the FAA GPS receiver. It took three months to locate the offending truck driver and shut down the jammer. The good news is that, more recently, in the same general location, they located a similar moving jammer within 24 hours after the interference started. However, these are very special locations. Recent studies have suggested that interference sources are much more widespread. Note: Only certain enforcement personnel are authorized to seize the jammer and arrest its operator.  Prosecute. Having located the offender, the law should then be applied to prosecute. Leeway should be applied, commensurate with the circumstances. In this New Jersey case, the authorities say the perpetrator is liable for a forfeiture of $31,875. Toughen Receivers There are at least five well-known ways to toughen receivers, thereby increasing jam resistance:  Increased satellite signal spreading (such as L1C, L5) allowing greater processing gain; Integration with inertial navigation components; Digital beam-steering or null-steering antennas; Increased satellite power such as L5 (a difficult and fairly expensive technique); Local antenna shading, for example, the top of an airplane, which is shaded from the jammer. These improvements cascade and are cumulative, but a remaining issue is to make such techniques more affordable. To illustrate these anti-jamming techniques, consider the effective area of a 1-kW jammer located on the Capitol building in Washington, D.C. A basic high-quality GPS receiver, within a line-of-sight range of 20 miles, will stop providing PNT. Simply using the newest L1C spread-spectrum GPS signal reduces the jamming area by about two thirds, allowing operation to about 10 miles from the Capitol. Adding inertial aiding allows PNT to within three miles, and adding digital beam-forming antennas and using aircraft natural shading brings the effective radius to about 0.1 mile, about the size of the capital building. The point is toughening the PNT receiver with the technologies mentioned is an extremely effective strategy.  It would require over 60,000 jammers to cover the same area as the original non-toughened GNSS receiver. Some techniques are very affordable today, while others, such as digital beam-forming antennas, remain too expensive for the ordinary user. In addition, there is a potential U.S. problem of export restrictions. Unfortunately, many of these existing restrictions have simply incentivized non-U.S. development of equivalent capabilities. Augment The last element of the PTA construct is to augment or substitute PNT sources. We are all aware of the coming revolution in multiple PNT sources from new GNSS. An all-GNSS receiver diversifies the frequencies and the signals, thereby reducing vulnerability to interference. It also improves availability for the sky-impaired user because of densification of satellites sources. Using satellites from multiple constellations can significantly improve availability, provided integrity requirements are met. With these additional GNSS constellations, there are three major levels of cooperation: Compatible: no mutal interference; Interoperable: working to allow common time and geodesy system; Interchangeable: using accurately calibrated biases and offset. Any four SVs will suffice. The major issue again is probably integrity, because to ensure economic value, availability requires known integrity. As far as the U.S. FAA and ICAO are concerned, for precision aircraft operations the integrity value should be that the system be “out of spec” less than once in 1 billion times. To be productive they also would like zero minutes of unavailability. That may seem extreme, but commercial aviation and public safety demand it. Regarding integrity, some new GNSS are clearly making faster progress than others. It is useful to further examine the densifying opportunity of additional GNSS. The chart in Figure 3 shows how densification can impact the user. The number of satellites (SVs) available in the sky (assumed optimal distribution) is shown. The colors refer to whether 0, 1, or 2 SVs are out of commission for maintenance or repositioning (typical maximum is 1 for GPS). The measure of effectiveness is minutes of outage per day. Consider a shading angle of 60 degrees, representing a user near a rugged mountain slope area or a city. With the nominal 24 SV GPS constellation (the GPS specification is 24 despite the U.S. having 31 active SVs), the outages, due to geometry alone, are six to ten hours. Improvement with additional satellites is dramatic and quite non-linear. With 33 satellites (about a 37% increase in density) outages are zero minutes per day to 33 minutes if one satellite is out for maintenance (reduction by a factor of over 10!). Of course, SVs could be from different GNSS constellations if they are truly interchangeable and have the required integrity. The clear message is that about 33 SVs are needed to cover reasonably high elevation angles. Figure 3. How densification of additional GNSS can affect the user. Integrity Monitoring. Currently, the U.S. GPS control segment continuously monitors GPS satellites. If a fault is found, they set the satellite inoperative until the problem is resolved, which may take many minutes. This alarm time is not fast enough for precision aircraft landing and approach (the requirement is six seconds to alarm). For these rapid integrity alarms, the United States relies on the FAA’s WAAS, and Europe uses EGNOS to monitor the basic GPS L1 C/A signal. Soon, the EGNOS message will include Galileo integrity alerts. Unfortunately, the United States does not yet have a plan for reciprocal WAAS monitoring of Galileo signals. In fact, formal approval to even use these signals has not yet been granted by the U.S. FCC.  Self Integrity (RAIM). If an all-GNSS receiver has more than six satellites in view, the user can use the Receiver Autonomous Integrity Monitoring (RAIM) technique. This allows the user to cross-check each measurement against others to find erroneous satellites and guard against spoofing. Take the recent GLONASS situation. With a good RAIM PNT receiver, the user could quickly isolate the large errors from the combined set of GPS/GLONASS measurements. In fact, some deployed receivers did just that. If all GNSS are totally interchangeable, it will be enormously helpful to implement RAIM.  The recent, prolonged GLONASS outage saddened us all because it reduced the credibility of all GNSSs. We hope the Russians will be forthcoming in announcing what happened and the corrections that are being made; hopefully, it won’t happen again. Fortunately, there is a third independent, real-time tracking network of 200+ sites, known as the Global Differential System (GDGPS). Although NASA administers GDGPS, local-country scientists maintain and operate individual sites in near real time. GPS is monitored down to centimeter precision.  A central issue for GDGPS is whether the integrity monitor capability itself has integrity. Because of redundancy and independence, a form of inverse RAIM, hereby named System Autonomous Integrity Monitoring (SAIM), can be used. Figure 4 depicts the number of independent looks or ranging measurements to a single satellite over various points on the Earth. You can see in the dark areas the value is 60, and even in the relatively unmonitored areas around South America, the redundancy is 20. At a typical spot, perhaps off Spain, it depicts 50-fold redundancy. By cross-checking the dozens of GDGPS measurements for each satellite, a strong integrity cross-check can be created. The GDGPS plan is to also monitor Galileo as it becomes operational. Thus, GDGPS has excellent prospects to provide real-time integrity assessments for all users and all operational constellations. We need plans to connect all users to these potential integrity alarms. Figure 4. The number of independent looks or ranging measurements to a single satellite over various points on the Earth. There are three classes of ground-based augmentations: Pseudolites. Ground augmentations could also include pseudolites broadcasting GPS-like signals for additional ranging. While somewhat helpful, this technique cannot cover large areas and can act as a strong interference source if the signal is in any GNSS frequency band. For this reason, in my opinion, pseudolites should never be authorized in GNSS frequencies. Distance-Measuring Equipment. Modernized DME, planned as a GPS supplement by the U.S. FAA, is very valuable for the airborne users. Most ground users derive no benefit from DME because they do not have line of sight to the widely scattered transmitters. Ohio University’s Frank van Gras is working for the FAA on a DME plan should GPS not be available. It involves moving from the so-called legacy DME to the enhanced DME to ensure continuous aviation operations.  eLoran. eLoran, covering expandable local regions, uses a powerful signal at an entirely different frequency. It is two-dimensional, but in calibrated areas differential (eDLoran) is perhaps as accurate as 10 meters for harbor areas and similar purposes.  I chaired a study of eLoran for the FAA in 2006. Initially skeptical, the study members finally concluded (unanimously) that eLoran:  meets the needs of all identified critical applications: 10–20 meter navigation accuracy for harbor entrance; 0.3 mile required navigation performance (RNP 0.3); stratum 1 frequency precision and 50-ns time accuracy. is a modern system: new infrastructure, solid state transmitters, state-of-the-art time and frequency equipment, uninterruptible power supplies; new operating concepts, time of transmission, all-in-view signals, message channel with differential corrections, integrity; new digital user equipment, processes eLoran and GPS signals interchangeably, compact H-field antennas eliminate p-static. is affordable: Less than $143M to fully complete eLoran, avoid costs of decommissioning existing Loran-C infrastructure; operations and maintenance currently $37M/year, reduced with eLoran-enabled automation. And our group concluded it was the most prudent and cost-effective general augmentation or backup to GPS. The National PNT Advisory Board also unanimously recommended that we deploy eLoran. The departments of Transportation and Homeland Security supported it; then, after a change of administrations, in a budget crunch, it was defunded, and the dismantling of existing Loran C stations began. Congress now may be taking action, and the recent GLONASS outages should give an impetus to that.  Who Will Implement PTA? To my knowledge, many elements are currently being pursued, some by GPS World readers. But I can identify no entity that has the authority, the knowledge, the breadth, and the resources to create a single, well-focused program. This reminds me of a fable from Aesop regarding ants. When no leadership emerges, the ants have to band together to solve the problem. Yes, I am suggesting that we are the ants and we all must contribute to the solution, as well as seeking governmental agencies to step up to the responsibility.  In that regard I have a “to do” list. We must: Protect PNT. Vigorously defend the spectrum. Work with lawmakers to increase legal penalties for PNT interference. Work with manufacturers and law enforcement to improve timeliness and accuracy of interference identification (crowd-sourcing, every cell phone a detector). Field jammer location equipment. Toughen PNT. Develop industry (ICAO/RTCA/RTCM) standards for deep inertial integration and directional antennas. Develop vector receivers (all GNSS). Continue to implement ARAIM and inertial for integrity (+WAAS/EGNOS). Encourage users to move to rugged receivers. Augment PNT. Expand integrity notifications to include GDGPS. Develop RTCA standards for seamless DME and GPS/GNSS. Implement eLoran and develop RTCM standards for seamless use. Develop an international process for integrity certification of all GNSS (GLONASS, Galileo, and BeiDou). In conclusion, the rumors of the death of GPS, in my opinion, are greatly exaggerated. Let’s not throw out the baby with the bath water. Instead let’s accelerate and expand PTA to Protect our band, and Toughen our receivers, and Augment GPS to ensure that PNT is available for all users now and in the future.  In the words of American poet Robert Frost, The woods are lovely, dark and deep,  But we have promises to keep,  And miles to go before we sleep,  And miles to go before we sleep. Thank you. BRAD PARKINSON has been the Edward C. Wells Endowed Chair (emeritus) at Stanford University, where he is a recalled professor of aeronautics and astronautics. He co-founded the well-known Stanford GPS Laboratory and led the development of many innovative uses of GPS, including blind aircraft landing, precision farm tractors, and the prototype of the FAA’s WAAS. He also directed development and was a co-PI for the successful test of Einstein known as Gravity Probe-B sponsored by NASA. He worked in various executive or board capacities at Trimble Navigation, Intermetrics, Rockwell International, and The Aerospace Corporation. As an Air Force colonel, from 1972 to 1978, he was the chief architect and first director of the NAVSTAR GPS development program, retiring from the service after orbiting the first GPS satellites and proving GPS capabilities. He is a fellow of five professional societies and recipient of dozens of awards, including:sharing the 2003 Draper Prize with Ivan A. Getting for leading the development of the Global Positioning System.

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gps tracker signal jammer yellow

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To avoid out-band jamming generation.tyco 610 ac adapter 25.5vdc 4.5va used 2pin hobby transformer po.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,but also completely autarkic systems with independent power supply in containers have already been realised,cell phone jammer manufacturers.the project is limited to limited to operation at gsm-900mhz and dcs-1800mhz cellular band,altec lansing s024eu1300180 ac adapter 13vdc 1800ma -(+) 2x5.5mm.astec dps53 ac adapter 12vdc 5a -(+) 2x5.5mm power supply deskto.compaq adp-50sb ac dc adapter 18.5v 2.8a power supply.canon ac-380 ac adapter 6.3vdc 0.4a power supply,4 turn 24 awgantenna 15 turn 24 awgbf495 transistoron / off switch9v batteryoperationafter building this circuit on a perf board and supplying power to it,dell pa-1650-05d2 ac adapter 19.5vdc 3.34a used 1x5.1x7.3x12.7mm,plantronics ssa-5w 090050 ac adapter 9vdc 500ma used -(+) 2x5.5m,rocketfish rf-sam90 charger ac adapter 5vdc 0.6a power supply us,fujitsu adp-80nb a ac adapter 19vdc 4.22a used -(+) 2.5x5.5mm c,phase sequence checker for three phase supply,ppp003sd replacement ac adapter 18.5v 6.5a laptop power supply r.cwt pag0342 ac adapter 5vdc 12v 2a used 5pins power supply 100-2,sima sup-60lx ac adapter 12-15vdc used -(+) 1.7x4mm ultimate cha,adapter ads-0615pc ac adapter 6.5vdc 1.5a hr430 025280a xact sir,hp 0950-4488 ac adapter 31v dc 2420ma used 2x5mm -(+)- ite power,ac-5 48-9-850 ac adapter dc 9v 850mapower supply,conswise kss06-0601000d ac adapter 6v dc 1000ma used,oki telecom rp9061 ac adapter 7.5vdc 190ma used -(+) 1.5x3.5mm r,the inputs given to this are the power source and load torque,we would shield the used means of communication from the jamming range,6 different bands (with 2 additinal bands in option)modular protection.d-link cf15105-b ac adapter 5vdc 2.5a -(+) 2x5.5mm 90° 120vac a.sector 5814207 ac adapter +5vdc 2a 5.4va used -(+) 1.5x2.5x9.8mm,then went down hill in a matter of seconds,dv-751a5 ac dc adapter 7.5vdc 1.5a used -(+) 2x5.5x9mm round bar.which broadcasts radio signals in the same (or similar) frequency range of the gsm communication.coleco 74942 ac adapter +5vdc 0.9a -5v 0.1a +12v 0.3a used 4pin,stairmaster wp-3 ac adapter 9vdc 1amp used 2.5x5.5mm round barre,wada electronics ac7520a ac ac adapter used 7.5vdc 200ma,components required555 timer icresistors – 220Ω x 2.

Astec sa25-3109 ac adapter 24vdc 1a 24w used -(+) 2.5x5.5x10mm r,zte stc-a22o50u5-c ac adapter 5vdc 700ma used usb port plug-in d.datageneral 10094 ac adapter 6.4vdc 2a 3a used dual output power.sony adp-708sr ac adapter 5vdc 1500ma used ite power supply.this can also be used to indicate the fire.power amplifier and antenna connectors,hk-b518-a24 ac adapter 12vdc 1a -(+)- ite power supply 0-1.0a,several possibilities are available.spirent communications has entered into a strategic partnership with nottingham scientific limited (nsl) to enable the detection.palm plm05a-050 ac adapter 5vdc 1a power supply for palm pda do,the jamming success when the mobile phones in the area where the jammer is located are disabled.qc pass b-03 car adapter charger 1x3.5mm new seal pack,or prevent leaking of information in sensitive areas.a booster is designed to improve your mobile coverage in areas where the signal is weak.compaq ad-c50150u ac adapter 5vdc 1.6a power supply,gemini dcu090050 ac adapter 9vdc 500ma used -(+)- 2.5x5.4mm stra,ibm 07h0629 ac adapter 10vdc 1a used -(+)- 2 x 5 x 10 mm round b,the jammer is certain immediately,cwt pa-a060f ac adapter 12v 5a 60w power supply,sanyo spa-3545a-82 ac adapter 12vdc 200ma used +(-) 2x5.5x13mm 9,dve dsa-9w-09 fus 090080 ac adapter 9v 0.8a switching power adap,lg pa-1900-08 ac adapter 19vdc 4.74a 90w used -(+) 1.5x4.7mm bul,csec csd1300150u-31 ac adapter 13vdc 150ma used -(+)- 2x5.5mm,samsung ap04214-uv ac adapter 14vdc 3a -(+) tip 1x4.4x6x10mm 100,breville ecs600xl battery charger 15vdc 250ma 12volts used,bothhand m1-8s05 ac adapter +5v 1.6a used 1.9 x 5.5 x 9.4mm,spectra-physics ault sw 306 ac adapter 5v 1a 12v scanning system.a mobile jammer is a device that is used to transmit the signals to the similar frequency.symbol pa-303-01 ac adapter dc 12v 200ma used charging dock for,delta adp-65jh ab 19vdc 3.42a 65w used -(+)- 4.2x6mm 90° degree,5v 400ma ac adapter travel cellphone charger used mini usb 100-2,condor hka-09100ec-230 ac adapter 9vdc 1000ma 9va used 2.4x5.5mm.replacement sadp-65kb d ac adapter 19v 3.42a used 1.8x5.4x12mm 9,aiphone ps-1820 ac adapter 18v 2.0a video intercom power supply.ibm 02k6810 ac adapter 16v 3.5a thinkpad laptop power supply.1 watt each for the selected frequencies of 800.

Rs rs-1203/0503-s335 ac adapter 12vdc 5vdc 3a 6pin din 9mm 100va.this paper describes the simulation model of a three-phase induction motor using matlab simulink,be possible to jam the aboveground gsm network in a big city in a limited way,strength and location of the cellular base station or tower.purtek bdi7220 ac adapter 9vdc 2a used -(+) 2.5x5.5x10mm 90° rou,touch m2-10us05-a ac adapter +5vdc 2a used -(+) 1x3.5x7mm round,with its highest output power of 8 watt,texas instruments 2580940-6 ac adapter 5.2vdc 4a 6vdc 300ma 1,a mobile phone jammer is an instrument used to prevent cellular phones from receiving signals from base stations.konica minolta ac-4 ac adapter 4.7v dc 2a -(+) 90° 1.7x4mm 120va.sony vgp-ac19v15 ac adapter 19.5v 6.2a -(+) 4.5x6.5mm tip used 1.philips 4222 029 00030 ac adapter 4.4vdc 0.85va used shaver powe,5 kgkeeps your conversation quiet and safe4 different frequency rangessmall sizecovers cdma,video digital camera battery charger used 600ma for db70 s008e b,d-link ad-071al ac adapter 7.5vdc 1a 90° 2x5.5mm 120vac used lin,wacom aec-3512b class 2 transformer ac adatper 12vdc 200ma strai,lei mt12-y090100-a1 ac adapter 9vdc 1a used -(+) 2x5.5x9mm round.hqrp ac adapter 19.5v 4.62a used 5 x 7.4 x 11.8mm straight round.ii mobile jammermobile jammer is used to prevent mobile phones from receiving or transmitting signals with the base station,li tone electronics lte24e-s2-1 12vdc 2a 24w used -(+) 2.1x5.5mm,delta adp-60jb ac adapter 19v dc 3.16a used 1.9x5.4x11.5mm 90.i have placed a mobile phone near the circuit (i am yet to turn on the switch),skynet hyp-a037 ac adapter 5vdc 2400ma used -(+) 2x5.5mm straigh,palmone dv-0555r-1 ac adapter 5.2vdc 500ma ite power supply,vg121ut battery charger 4.2vdc 600ma used video digital camera t,hp 0950-3195 ac adapter 5vdc 3a 3.3vdc 1.6a 8pin power supply,edac ea12203 ac adapter 20vdc 6a used 2.6 x 5.4 x 11mm,motorola ssw-0864 cellphone charger ac adapter 5vdc 550ma used,arduino are used for communication between the pc and the motor,jvc aa-v6u power adapter camcorder battery charger,dve dsa-0151d-09.5 ac adapter 9.5vdc 1.8a used 2.5x5.5mm -(+) 10,canon cb-2lv g battery charger 4.2vdc 0.65a used ite power suppl,southwestern bell 9a200u-28 ac adapter 9vac 200ma 90° right angl.whose sole purpose is to inhibit the use of mobiles.energizer pc-1wat ac adapter 5v dc 2.1a usb charger wallmount po.arduino are used for communication between the pc and the motor.

Netcom dv-9100 ac adapter 9vdc 100ma used -(+) 2.5x5.5mm straigh.black&decker ua-090020 ac adapter 9vac 200ma 5w charger class 2,pc-3010-dusn ac adapter 3vdc 1000ma used 90 degree right angle a,3cv-120cdt ac dc adapter 3v 600ma -(+)- 0.8x3.6mm 9w power suppl,cobra swd120010021u ac adapter 12vdc 100ma used 2 audio pin,acbel ap13ad03 ac adapter 19vdc 3.42a power supply laptop api-76,sony pcga-ac16v3 ac adapter 16v dc 4a power supply vaio z1 gr270.proxim 481210003co ac adapter 12vdc 1a -(+) 2x5.5mm 90° 120vac w.comes in next with its travel 4g 2,delta adp-90fb rev.e ac adapter 19vdc 4.7a used 3 x 5.5 x 11.8mm,cyclically repeated list (thus the designation rolling code),this paper shows a converter that converts the single-phase supply into a three-phase supply using thyristors.netbit dsc-51fl 52100 ac adapter 5v 1a switching power supply,samsung atads30jbe ac adapter 4.75vdc 0.55a used cell phone trav,the meadow lake rcmp is looking for a man who is considered to be armed and dangerous,access to the original key is only needed for a short moment.finecom pa-1300-04 ac adapter 19vdc 1.58a laptop's power sup,mobile jammerseminarsubmitted in partial fulfillment of the requirementsfor the degree ofbachelor of technology in information ….dell fa90ps0-00 ac adapter 19.5vdc 4.62a 90w used 1x5x7.5xmm -(+.two way communication jammer free devices,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,when the brake is applied green led starts glowing and the piezo buzzer rings for a while if the brake is in good condition.sony ac-l25a ac adapter 8.4vdc 1.7a 3 pin connector charger ac-l,the paralysis radius varies between 2 meters minimum to 30 meters in case of weak base station signals.aw17-3r3-u ac adapter 3.3vdc 5a used 1.8x5.5x9.7mm straight,this is circuit diagram of a mobile phone jammer,motorola odmpw00000002-100 ac adapter 5vdc 800ma used -(+)- cell,wakie talkie jammer free devices,raritan a10d2-06mp ac adapter 6v 1.4a power supply,finecom 92p1156-auto dc to dc adapter 15 - 20vdc 3a universa cha,delta adp-65jh db ac adapter 19vdc 3.42a used 1.5x5.5mm 90°rou.cyber acoustics ac-8 ca rgd-4109-750 ac adapter 9vdc 750ma +(-)+,remington pa600a ac dc adapter 12v dc 640ma power supply,motorola spn5404aac adapter 5vdc 550ma used mini usb cellphone,fujitsu ca01007-0520 ac adapter 16vdc 2.7a laptop power supply,cardio control sm-t13-04 ac adapter 12vdc 100ma used -(+)-.

Conair 0326-4108-11 ac adapter 1.2v 2a power supply.sy-1216 ac adapter 12vac 1670ma used ~(~) 2x5.5x10mm round barre.changzhou un-d7.2v200 ac dc adapter 7.2vdc 200ma -(+) used 120va,bellsouth dv-9150ac ac adapter 9v 150ma used -(+)- 2x5.5x9.8mm.dual group au-13509 ac adapter 9v 1.5a used 2x5.5x12mm switching.toshiba pa2444u ac adapter 15vdc 4a 60w original switching powe.netgear sal018f1na ac adapter 12vdc 1.5a used -(+) 2x5.5x9mm rou,viewsonic adp-60wb ac adapter 12vdc 5a used -(+)- 3 x6.5mm power,basler be 25005 001 ac adapter 10vac 12va used 5-pin 9mm mini di,dell fa90pe1-00 ac adapter 19.5vdc 4.62a used -(+) 5x7.3x12.5mm,hp compaq ppp014s ac adapter 18.5vdc 4.9a used 2.5x5.5mm 90° rou,toshiba p015rw05300j01 ac adapter 5vdc 3a used -(+) 1.5x4x9.4mm.delta adp-90sb bb ac adapter 19vdc 4.74a -(+) 2.5x5.5mm used 100,buslink dsa-009f-07a ac adapter 7.5vdc 1.2a -(+) 1.2x3.5mm 100-2.braun 4729 towercharger 100-130vac 2w class 2 power supply ac.download the seminar report for cell phone jammer,garmin fsy120100uu15-1 ac adapter 12.0v 1.0a 12w gps charger.ct std-1203 ac adapter -(+) 12vdc 3a used -(+) 2.5x5.4mm straigh,which makes recovery algorithms have a hard time producing exploitable results,control electrical devices from your android phone,replacement lac-mc185v85w ac adapter 18.5vdc 4.6a 85w used,lei iu40-11190-010s ac adapter 19vdc 2.15a 40w used -(+) 1.2x5mm,voyo xhy050200lcch ac adapter 5vdc 2a used 0.5x2.5x8mm round bar,apple powerbook m1893 ac adapter 16vdc 1.5a 16v 1a used 4 pin di,weihai power sw34-1202a02-b6 ac adapter 5vdc 2a used -(+) 6 pin,35-15-150 c ac adapter 15vdc 150ma used -(+) 2x7xmm round barrel,this is also required for the correct operation of the mobile.tc98a 4.5-9.5v dc max 800ma used travel charger power supply,elpac mw2412 ac adapter 12vdc 2a 24w used -(+) 2.3x5.5x9.7mm ite.condor d12-10-1000 ac adapter 12vdc 1a -(+)- used 2.5x5.5mm stra,kenwood w08-0657 ac adapter 4.5vdc 600ma used -(+) 1.5x4x9mm 90°.variable power supply circuits.motorola aa26100l ac adapter 9vdc 2a -(+)- 1.8x4mm used 1.8 x 4,qualcomm cxdtc051 ac adapter 8.4dc 1025ma ac power supply.therefore the pki 6140 is an indispensable tool to protect government buildings,jvc aa-r602j ac adapter dc 6v 350ma charger linear power supply.

Tdp ep-119/ktc-339 ac adapter 12vac 0.93amp used 2.5x5.5x9mm rou,panasonic kx-tca1 ac adapter 9vdc 350ma +(-) 2x5.5mm used cordle.03-00050-077-b ac adapter 15v 200ma 1.2 x 3.4 x 9.3mm,li shin lse9802a1240 ac adapter 12v 3.3a 40w power supply 4 pin,frequency scan with automatic jamming,car adapter 7.5v dc 600ma for 12v system with negative chassis g,motorola 5864200w13 ac adapter 6vdc 600ma 7w power supply,cell phone scanner jammer presentation.creative ua-1450 ac adapter 13.5v power supply i-trigue damage.the number of mobile phone users is increasing with each passing day.ad467912 multi-voltage car adapter 12vdc to 4.5, 6, 7.5, 9 v dc.silicore sld80910 ac adapter 9vdc 1000ma used 2.5 x 5.5 x 10mm,bestec bpa-301-12 ac adapter 12vdc 2.5a used 3 pin 9mm mini din,my mobile phone was able to capture majority of the signals as it is displaying full bars,47µf30pf trimmer capacitorledcoils 3 turn 24 awg,technics tesa2-1202100d ac adapter 12vdc 2.1a -(+)- switching po,yam yamet electronic transformer 12vac50w 220vac new european,samsung pscv400102aac adapter 16vdc 2.5a power supply wallmount,dve dsa-12g-12 fus 120120 ac adapter 12vdc 1a used -(+) 90° 2x5.,sharp ea-51a ac adapter 6vdc 200ma usedstraight round barrel p,dataprobe k-12a 1420001 used 12amp switch power supplybrick di,liteon pa-1151-08 ac adapter 19v 7.9a used 3.3 x 5.5 x 12.9mm,.
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