Cell phone jammer schematic - hidden cellphone jammer bus

Handling the Biases for Improved Triple-Frequency PPP Convergence By Denis Laurichesse Precise point positioning (PPP) can be considered a viable tool in the kitbag of GPS positioning techniques. One precision aspect of PPP is its use of carrier-phase measurements rather than just pseudoranges. But there is a catch. Often many epochs of measurements are needed for a position solution to converge to a sufficiently high accuracy. In this month’s column, we look at how using measurements from three satellite frequencies rather than just two can help. INNOVATION INSIGHTS by Richard Langley PPP? WHAT’S THAT? This acronym stands for precise point positioning and, although the technique is still in development, it has evolved to a stage where it can be considered another viable tool in the kitbag of GPS positioning techniques. It is now supported by a number of receiver manufacturers and several free online PPP processing services. You might think, looking at the name, that there’s nothing particularly special about it. After all, doesn’t any kind of positioning with GPS give you a precise point position including that from a handheld receiver or a satnav device? They key word here is precise. The use of the word precise, in the context of GPS positioning, usually means getting positional information with precision and accuracy better than that afforded by the use of L1 C/A-code pseudorange measurements and the data provided in the broadcast navigation messages from the satellites. A typically small improvement in precision and accuracy can be had by using pseudoranges determined from the L2 frequency in addition to L1. This permits the real-time correction for the perturbing effect of the ionosphere. Such an improvement in positioning is embodied in the distinction between the two official GPS levels of service: the Standard Positioning Service provided through the L1 C/A-code and the Precise Positioning Service provided for “authorized” users, which requires the use of the encrypted P-code on both the L1 and L2 frequencies. Civil GPS users will have access to a similar level of service once a sufficient number of satellites transmitting the L2 Civil (L2C) code are in orbit. However, this capability will only provide meter-level accuracy. The PPP technique can do much better than this. It can do so thanks to two additional precision aspects of the technique. The first is the use of more precise (and, again, accurate) descriptions of the orbits of the satellites and the behavior of their atomic clocks than those included in the navigation messages. Such data is provided, for example, by the International GNSS Service (IGS) through its global tracking network and analysis centers. These so-called precise products are typically used to process receiver data after collection in a post-processing mode, although real-time correction streams are now being provided by the IGS and some commercial entities. Now, it’s true that a user can get high precision and accuracy in GPS positioning using the differential technique where data from one or more base or reference stations is combined with data from the user receiver. However, by using precise products and a very thorough model of the GPS observables, the PPP technique does away with the requirement for a directly accessed base station. The other precision aspect of PPP is its use of carrier-phase measurements rather than just pseudoranges. Carrier-phase measurements have a precision on the order of two magnitudes (a factor of 100) better than that of pseudoranges. But there is a catch to the use of carrier-phase measurements: they are ambiguous by an integer multiple of one cycle. Processing algorithms must resolve the value of this ambiguity and ideally fix it at its correct integer value. Unfortunately, it is difficult to do this instantaneously, and often many epochs of measurements are needed for a position solution to converge to a sufficiently high accuracy, say better than 10 centimeters. Researchers are actively working on reducing the convergence time, and in this month’s column, we look at how using measurements from three satellite frequencies rather than just two can help. “Innovation” is a regular feature that discusses advances in GPS technology and its applications as well as the fundamentals of GPS positioning. The column is coordinated by Richard Langley of the Department of Geodesy and Geomatics Engineering, University of New Brunswick. He welcomes comments and topic ideas. To contact him, see the “Contributing Editors” section on page 6. While carrier-phase measurements typically have very low noise compared to pseudorange (code) measurements, they have an inherent integer cycle ambiguity: the carrier phase, interpreted as a range measurement, is ambiguous by any number of cycles. However, integer ambiguity fixing is now routinely applied to undifferenced GPS carrier-phase measurements to achieve precise positioning. Some implementations are even available in real time. This so-called precise point positioning (PPP) technique permits ambiguity resolution at the centimeter level. With the new modernized satellites’ capabilities, performing PPP with triple-frequency measurements will be possible and, therefore, the current dual-frequency formulation will not be applicable. There is also a need for a generalized formulation of phase biases for Radio Technical Commission for Maritime Services (RTCM) State Space Representation (SSR) needs. In this RTCM framework, the definition of a standard is important to allow interoperability between the two components of a positioning system: the network side and the user side. Classical Formulation In this section, we review the formulation of the observation equations. We will use the following constants in the equations: where f1 and f2 are the two primary frequencies transmitted by all GPS satellites and c is the vacuum speed of light. For the GPS L1 and L2 bands, f1 = 154f0 and f2 = 120f0, where f0 = 10.23 MHz. The pseudorange (or code) measurements, P1 and P2, are expressed in meters, while phase measurements, L1 and L2, are expressed in cycles. In the following, we use the word “clock” to mean a time offset between a receiver or satellite clock and GPS System Time as determined from either code or phase measurements on different frequencies or some combination of them. The code and phase measurements are modeled as:   (1) where: D1 and D2 are the geometrical propagation distances between the emitter and receiver antenna phase centers at f1 and f2 including troposphere elongation, relativistic effects and so on. W is the contribution of the wind-up effect (in cycles). e is the code ionosphere elongation in meters at f1. This elongation varies with the inverse of the square of the carrier frequency and is applied with the opposite sign for phase. Δh = hi – hj is the difference between receiver i and emitter j ionosphere-free phase clocks. Δhp is the corresponding term for code clocks. Δτ = τi – τj is the difference between receiver i and emitter j offsets between the phase clocks at f1 and the ionosphere-free phase clocks. By construction, the corresponding quantity at f2 is γΔτ. Similarly, the corresponding quantity for the code is Δτp (time group delay). N1 and N2 are the two carrier-phase ambiguities. By definition, these ambiguities are integers. Unambiguous phase measurements are therefore L1 + N1 and L2 + N2. Equations (1) take into account all the biases related to delays and clock offsets. The four independent parameters, Δh, Δτ, Δhp, and Δτp, are equivalent to the definition of one clock per observable. However, our choice of parameters emphasizes the specific nature of the problem by identifying reference clocks for code and phase (Δhp and Δh) and the corresponding hardware offsets (Δτp and Δτ). These offsets are assumed to vary slowly with time, with limited amplitudes. The measured widelane ambiguity,  , (also called the Melbourne-Wübbena widelane) can be written as: (2) where Nw is the integer widelane ambiguity, μ j is the constant widelane delay for satellite j and μi is the widelane delay for receiver i (which is fairly stable for good quality geodetic receivers). The symbol  means that all quantities have been averaged over a satellite pass. Integer widelane ambiguities are then easily identified from averaged measured widelanes corrected for satellite widelane delays. Once integer widelane ambiguities are known, the ionosphere-free phase combination can be expressed as   (3) where     is the ionosphere-free phase combination computed using the known Nw ambiguity, Dc is the propagation distance, hi is the receiver clock and h j is the satellite clock. N1 is the remaining ambiguity associated to the ionosphere-free wavelength λc (10.7 centimeters). The complete problem is thus transformed into a single-frequency problem with wavelength λc and without any ionosphere contribution. Many algorithms can be used to solve Equation (3) using data from a network of stations. If Dc is known with sufficient accuracy (typically a few centimeters, which can be achieved using a good floating-point or real-valued ambiguity solution), it is possible to simultaneously solve for N1 , hi and h j. The properties of such a solution have been studied in detail. A very interesting property of the h j satellite clocks is, in particular, the capability to directly fix (to the correct integer value) the N1 values of a receiver that was not part of the initial network. The majority of the precise-point-positioning ambiguity-resolution (PPP-AR) implementations are based on the identification and use of the two quantities μ j and h j. These quantities may be called widelane biases and integer phase clocks, a decoupled clock model or uncalibrated phase delays, but they are all of the same nature. A Real-Time PPP-AR Implementation A PPP-AR technique was successfully implemented by the Centre National d’Etudes Spatiales (CNES) in real time in the so-called PPP-Wizard demonstrator in 2010 and has been subsequently improved. In this demonstrator and in the framework of the International GNSS Service (IGS) Real-Time Service (RTS) and the RTCM, the GPS and GLONASS constellation orbits and clocks are computed. Additional biases for GPS ambiguity resolution are computed and broadcast to the user. The demonstrator also provides an open-source implementation of the method on the user side, for test purposes. Centimeter-level positioning accuracy in real time is obtained on a routine basis. Limitations of the Bias Formulations. The current formulation works but it has several drawbacks: The chosen representation is dependent on the implemented method. Even if the nature of the biases is the same, their representation may be different according to the underlying methods, and this makes it difficult for a standardization of the bias messages. The user side must implement the same method as the one used on the network side. Otherwise, the user side would have to convert the quantities from one method to another, leading to potential bugs or misinterpretations. It is limited to the dual-frequency case. There are only two quantities to be computed in the dual-frequency case ( and ), but in the triple-frequency case, there are many more possible combinations. For example, one can have (this is a non-exhaustive list) , , ,, , , where the indices refer to different pairs of frequencies, and other ionosphere-free combinations such as phase widelane-only or even phase ionosphere-free and geometry-free combinations are possible. New RTCM SSR Model The new model, as proposed by the RTCM Special Committee 104 SSR working group for phase bias messages is based on the idea that the phase bias is inherent to each frequency. Thus, instead of making specific combinations, one phase bias per phase observable is identified and broadcast. It is noted that this convention was adopted a long time ago for code biases. Indeed, in the RTCM framework, and unlike the standard differential code bias (DCB) convention where code biases are undifferenced but combined, the RTCM SSR code biases are defined as undifferenced and uncombined. The general model for uncombined code and phase biases is therefore:    (4) Time group delays, τ, and phase clocks, h, in Equation (1) are replaced by code and phase biases (ΔbP and ΔbL respectively). RTCM SSR code and phase biases correspond to the satellite part of these biases. The prime notation denotes the “unbiasing” process of the measurements. Here, the clock definition is crucial. As the biases are uncombined, they are referenced to the clocks. The convention chosen for the standard is natural: it is the same as the one used by IGS, that is, ΔhP in our notation. This new model can be extended to the triple-frequency case very easily, as it does not involve explicit dual-frequency combinations:     (5) This new model simplifies the concept of phase biases for ambiguity resolution. This representation is very attractive because no assumption is made on the method used to identify phase biases on the network side. All the implementations are valid if they respect this proposed model. It also allows convenient interoperability if the network and user sides implement different ambiguity resolution methods. TABLE 1 summarizes the different messages used for PPP-AR in the context of RTCM SSR: TABLE 1. RTCM SSR messages for PPP-AR. Bias Estimation in the Dual-Frequency Case. The new phase biases identification in the dual-frequency case is straightforward. There are two biases (,  ) to be estimated using two combinations (µ and h). The problem to be solved is described in FIGURE 1. FIGURE 1. Phase biases estimation in the dual-frequency case. It can be solved very easily on the network side by means of a 2 × 2 matrix inversion:    (6) with Note: All the quantities denote the satellite part of the Δ operator defined above. Bias Estimation in the Triple-Frequency Case. The triple-frequency bias identification is tricky due to the need, using only three biases, to keep the integer nature of phase ambiguities on all viable ionosphere-free combinations, and in particular combinations that were not used in the identification process. At this level, one cannot make assumptions on what kind of combinations will be employed by a user. The problem to be solved is described in FIGURE 2. FIGURE 2. Phase biases estimation in the triple-frequency case. As an example, a naïve solution would be to identify the extra-widelane phase biases,, using the dual-frequency widelane approach, and then identify thebias. Given the large wavelength of the extra-widelane combination, such identification would be very easy. However, the corresponding bias would be only helpful for extra-widelane ambiguity identification, and its noise would prevent its use for widelane 15 (L1/L5) ambiguity resolution or other useful combinations available in the triple-frequency context. Each independent phase bias can be directly estimated in a filter; however, in order to keep ascending compatibility with the dual-frequency case during the deployment phase of the new modernized satellites, we have chosen to stay in the old framework, that is, to work with combinations of biases. The resolution method is the following: The widelane biases, that is, the identification of all the bLi – bLj quantities, are solved. For this computation and in order to have an accurate estimate of these biases, the two MW-widelane biases µ12 and µ15 are used coupled to an additional phase bias, which is given by the triple-frequency ionosphere-free phase combination with the integer widelane ambiguities already fixed. This last combination using only phase measurements is much more accurate than MW-widelanes. The system to be solved is redundant and the noise of the different equations has to be chosen carefully. The remaining bias (bLi ) is estimated using the traditional ionosphere-free phase combination of L1 and L2. This computation has been implemented in the CNES real-time analysis center software, and since September 15, 2014, CNES broadcasts phase biases compatible with this triple-frequency concept on the IGS CLK93 real-time data stream. Real Data Analysis To prove the validity of the concept, at CNES, we compute several ambiguity combinations using real data. The process is the following: Look for good receiver locations having a large number of GPS Block IIF satellites (transmitting the L5 signal) in view for a period of time exceeding 30 minutes, and choose among them, one participating in the IGS Multi-GNSS (MGEX) experiment. The station CPVG (Cape Verde) in the Reseau GNSS pour l’IGS et la Navigation (REGINA) network was chosen for the time span on September 28, 2014, between 19 and 20 hours UTC. During this period, four Block IIF satellites were visible simultaneously (PRNs 1, 6, 9, 30) for a total of 14 GPS satellites in view. Record a compatible phase-bias stream. The CLK93 stream is recorded during the time span of the experiment. Perform a PPP solution using the measurements, CLK93 corrections and biases to estimate the propagation distance, the troposphere delay and the receiver clock and phase ambiguity estimates according to Equation (5). For different ambiguity estimates, compute and plot the obtained residuals. We present in the following graphs various ambiguity residuals for the four Block IIF satellites in view. The values of each ambiguity are offset by an integer value for clarity purposes. Melbourne-Wübbena Extra-Widelane. FIGURE 3 represents the MW extra-widelane (between frequencies L2 and L5) ambiguity estimation using our process. The MW extra-widelane ambiguity has a wavelength of 5.86 meters. The noise of the combination expressed in cycles is very low, and the integer nature of ambiguities in this combination is clearly visible. FIGURE 3. Ambiguity residuals for the extra-widelane 5-2 combination. Melbourne-Wübbena Widelanes. FIGURE 4 represents the MW-widelanes (the regular 1-2 and 1-5 combinations). Here again, the integer nature of the four ambiguities is clearly visible. FIGURE 4. Ambiguity residuals for widelane combinations; top: 1-2 widelane, bottom: 1-5 widelane. Widelane-Only Ionosphere-Free Phase. In the triple-frequency context, there is a possibility of forming an ionosphere-free combination of the three phase observables. This combination has an important noise amplification factor (>20), but would allow us to perform decimeter-accuracy PPP using only the solved widelane integer ambiguities and if the corresponding phase biases are accurate. In addition, it can be shown that the wavelength of the widelane ambiguity when the extra-widelane ambiguity is solved is about 3.4 meters. It means that the remaining widelane using this combination can be solved if the position is accurate enough (a few tens of centimeters) and the extra-widelane is known. FIGURE 5 shows such a case, that is, the residuals of the widelane ambiguity using this combination and assuming that the extra-widelane is already solved for. FIGURE 5. Ambiguity residuals for widelane-only 1-2-5 ionosphere free combinations. Such a case where the solution is the most biased  is shown (the dark blue curve). This behavior is mainly due to the difficulty in estimating the phase biases on this combination accurately using only a few Block IIF satellites. We hope that in the future the increasing number of modernized satellites will help such bias estimation. N1 Ionosphere-Free Phase. FIGURES 6 to 8 show the three possible ambiguity estimates using the ionosphere-free phase combination with two measurements (we assume that the corresponding widelane has already been solved). In each case, the computed biases allow us to easily retrieve the integer nature of the N1 ambiguity. FIGURE 6. Ambiguity residuals for the N1 combination using a fixed 1-2 widelane. FIGURE 7. Ambiguity residuals for the N1 combination using a fixed 1-5 widelane. FIGURE 8. Ambiguity residuals for the N1 combination using a fixed 2-5 widelane. Application to Triple-Frequency PPP The results presented above show that the integer ambiguity nature of phase measurements is conserved for various useful observable combinations and prove the validity of the model. Another experiment has been carried out to estimate the impact of ambiguity convergence in the triple-frequency context. For that, in order to maximize the observability of the GPS Block IIF constellation and thus the accuracy of the biases, a network of ten stations across Europe has been chosen for the phase biases computation (see FIGURE 9). The station REDU (in green) was the test station to be positioned. The test occurred on January 10, 2015, around 11:00 UTC. At that time, four Block IIF satellites were visible simultaneously (PRNs 1, 3, 6, 9) for a total of 10 satellites in view. FIGURE 9. Network used for the triple-frequency PPP study. The PPP-Wizard open source client was used to perform PPP in real time. The advantage of this implementation is that it directly follows the uncombined observable formulation described in Equations (5). The strategy for ambiguity resolution is a simple bootstrap approach. Convergence of the Widelane-Only Solution. In this test, a PPP solution was performed, but only the fixing of the widelane ambiguities was implemented. As noted in the previous section, the wavelength of the widelane ambiguity when the extra-widelane ambiguity is solved is about 3.4 meters, so it is expected that all the widelanes can be fixed in a very short time. Despite the amplification factor of about 20 of the equivalent unambiguous phase combination, we expect to obtain an accuracy of about 10 centimeters with such a solution. FIGURE 10 shows the convergence time of several PPP runs in this context (16 different runs of five minutes are superimposed), in terms of horizontal position error. FIGURE 10. Widelane-only triple-frequency PPP convergence (horizontal position error). The extra-widelanes are fixed instantaneously; the remaining widelanes are fixed in about two minutes on average to be below 30 centimeters (this is represented by the different sharp reductions of the errors). This new configuration, available in the triple-frequency context, is very interesting as it provides an intermediate class of accuracy, which converges very quickly and which is suitable for applications that do not demand centimeter accuracy. Another interesting aspect of this combination is the gap-bridging feature. In PPP, gap-bridging is the functionality that allows us to recover the integer nature of the ambiguities after a loss of the receiver measurements over a short period of time (typically a pass through a tunnel or under a bridge). This is done usually by means of the estimation of a geometry-free combination (ionosphere delay estimation) during the gap. Realistic maximum gap duration in the dual-frequency case is about one minute. In the triple-frequency case, the wavelength of the geometry-free combination involving the widelane (if the extra-widelane is fixed) is 1.98 meters. With such a large wavelength, the gaps are much easier to fill, and we can safely extend the gap duration to several minutes. In addition, the widelane combinations are wind-up independent, so there is no need to monitor a possible rotation of the antenna during the gap, as in the dual-frequency case. Overall Convergence (All Ambiguities). Another PPP convergence test has been carried out with all ambiguities fixing activated (four different runs of 15 minutes are superimposed). Results are shown in FIGURE 11. FIGURE 11. All ambiguities triple-frequency PPP convergence (horizontal position error). The centimeter accuracy is obtained in this configuration within eight minutes, which is a significant improvement in comparison to the dual-frequency case. Further improvement of this convergence time is expected with an increase in the number of Block IIF satellites and, subsequently, GPS IIIA satellites. Convergence Time Comparison Between the Dual- and Triple-Frequency Contexts. Thanks to these new results, a realistic picture for PPP convergence in the dual- and triple-frequency contexts can be drawn. To do so, polynomial functions have been fitted over the data points obtained in the previous studies. Two data sets were used: Standard dual-frequency convergence (GPS only, 10 satellites in view). Triple-frequency convergence (GPS only, 10 satellites in view, four Block IIF satellites). FIGURE 12 represents the comparison between the two polynomials (horizontal error). FIGURE 12. Realistic PPP convergence comparison between dual- and triple-frequency contexts (horizontal position error). Conclusion The new phase-bias concept proposed for RTCM SSR has been successfully implemented in the CNES IGS real-time analysis center. This new concept represents the phase biases in an uncombined form, unlike the previous formulations. It has the advantage of the unification of the different proposed methods for ambiguity resolution, and it prepares us for the future; for example, for a widely available triple-frequency scenario. The validity of this concept has been shown; that is, the integer ambiguity nature of phase measurements is conserved for various useful observable combinations. In addition, we have also shown that the triple-frequency context has a significant impact on ambiguity convergence time. The overall convergence time is drastically reduced (to some minutes instead of some tens of minutes) and there is an intermediate combination (widelane-only) that has some interesting properties in terms of convergence time, accuracy and gap-bridging for non-demanding centimeter-level applications. Acknowledgments The contributions of colleagues contributing to the IGS services are gratefully acknowledged. Geo++ is thanked for useful discussions on the standardization of phase bias representation. DENIS LAURICHESSE received his engineering degree and a Diplôme d’études appliquées (an advanced study diploma) from the Institut National des Sciences Appliquées in Toulouse, France, in 1988. He has worked in the Spaceflight Dynamics Department of the Centre National d’Etudes Spatiales (CNES, the French Space Agency) in Toulouse since 1992, responsible for the development of the onboard GNSS Diogene navigator. He was involved in the performance assessment of the EGNOS and Galileo systems and is now in charge of the CNES International GNSS Service real-time analysis center. He specializes in navigation, precise satellite orbit determination and GNNS-based systems. He was the recipient of The Institute of Navigation Burka Award in 2009 for his work on phase ambiguity resolution. Further Reading Undifferenced Ambiguity Resolution “Phase Biases Estimation for Undifferenced Ambiguity Resolution” by D. Laurichesse, presented at PPP-RTK & Open Standards Symposium, Frankfurt, Germany, March 12–13, 2012. “Undifferenced GPS Ambiguity Resolution Using the Decoupled Clock Model and Ambiguity Datum Fixing” by P. Collins, S. Bisnath, F. Lahaye, and P. Héroux in Navigation, Journal of The Institute of Navigation, Vol. 57, No. 2, Summer 2010, pp. 123–135, doi: 10.1002/j.2161-4296.2010.tb01772.x. “Integer Ambiguity Resolution on Undifferenced GPS Phase Measurements and Its Application to PPP and Satellite Precise Orbit Determination” by D. Laurichesse, F. Mercier, J.-P. Berthias, P. Broca, and L. Cerri in Navigation, Journal of The Institute of Navigation, Vol. 56, No. 2, Summer 2009, pp. 135–149, doi: 0.1002/j.2161-4296.2009.tb01750.x. “Resolution of GPS Carrier-Phase Ambiguities in Precise Point Positioning (PPP) with Daily Observations” by M. Ge, G. Gendt, M. Rothacher, C. Shi, and J. Liu in Journal of Geodesy, Vol. 82, No. 7, pp. 389–399, doi: 10.1007/s00190-007-0187-4. Erratum: 10.1007/s00190-007-0208-3. Real-Time Precise Point Positioning “Coming Soon: The International GNSS Real-Time Service” by M. Caissy, L. Agrotis, G. Weber, M. Hernandez-Pajares, and U. Hugentobler in GPS World, Vol. 23, No. 6, June 2012, pp. 52–58. “The CNES Real-time PPP with Undifferenced Integer Ambiguity Resolution Demonstrator” by D. Laurichesse in Proceedings of ION GNSS 2011, the 24th International Technical Meeting of The Satellite Division of the Institute of Navigation, Portland, Ore, September 20–23, 2011, pp. 654–662.  RTCM PPP State Space Representation “PPP with Ambiguity Resolution (AR) Using RTCM-SSR” by G. Wübbena, M. Schmitz, and A. Bagge, presented at IGS Workshop, Pasadena, Calif., June 23–27, 2014. “The RTCM Multiple Signal Messages: A New Step in GNSS Data Standardization” by A. Boriskin, D. Kozlov, and G. Zyryanov in Proceedings of ION GNSS 2012, the 25th International Technical Meeting of The Satellite Division of the Institute of Navigation, Nashville, Tenn., September 17–21, 2012, pp. 2947-2955. “RTCM State Space Representation (SSR): Overall Concepts Towards PPP-RTK” by G. Wübbena, presented at PPP-RTK & Open Standards Symposium, Frankfurt, Germany, March 12–13, 2012. Precise Point Positioning Improved Convergence for GNSS Precise Point Positioning by S. Banville, Ph.D. dissertation, Department of Geodesy and Geomatics Engineering, Technical Report No. 294, University of New Brunswick, Fredericton, New Brunswick, Canada. Recipient of The Institute of Navigation 2014 Bradford W. Parkinson Award. “Precise Point Positioning: A Powerful Technique with a Promising Future” by S.B. Bisnath and Y. Gao in GPS World, Vol. 20, No. 4, April 2009, pp. 43–50.    

cell phone jammer schematic

Icm06-090 ac adapter 9vdc 0.5a 6w used -(+) 2x5.5x9mm round barr,a break in either uplink or downlink transmission result into failure of the communication link,here is the diy project showing speed control of the dc motor system using pwm through a pc.motorola dch3-05us-0300 travel charger 5vdc 550ma used supply,mw mw1085vg ac adapter 10vdc 850ma new +(-)2x5.5x9mm round ba.a&d tb-233 ac adapter 6v dc 500ma used -(+) 2x5.5mm barrel 120va,dve dsa-0051-03 fus ac adapter 5vdc 0.5a mini usb charger,rayovac ps6 ac adapter 14.5 vdc 4.5a class 2 power supply.tiger power tg-4201-15v ac adapter 15vdc 3a -(+) 2x5.5mm 45w 100,225univ walchgr-b ac adapter 5v 1a universal wall charger cellph,atlinks usa inc. 5-2509 ac dc adapter 9v 450ma 8w class 2 power,large buildings such as shopping malls often already dispose of their own gsm stations which would then remain operational inside the building,a retired police officer and certified traffic radar instructor,toshiba pa3049u-1aca ac adapter 15v 3a power supply laptop,netline communications technologies ltd,pure energy cs4 charging station used 3.5vdc 1.5a alkaline class.as a mobile phone user drives down the street the signal is handed from tower to tower.hp hstn-f02g 5v dc 2a battery charger with delta adp-10sb,the black shell and portable design make it easy to hidden and use.nikon eh-69p ac adapter 5vdc 0.55a used usb i.t.e power supply 1.it is efficient in blocking the transmission of signals from the phone networks,us robotics dv-9750-5 ac adapter 9.2vac 700ma used 2.5x 5.5mm ro.ku2b-120-0300d ac adapter 12vdc 300ma -o ■+ power supply c,butterfly labs ac adapter 13vdc 31a 2x 6pin pci-e bfl power supp,wifi) can be specifically jammed or affected in whole or in part depending on the version,cell phone jammer is an electronic device that blocks transmission of ….hon-kwang hk-h5-a12 ac adapter 12vdc 2.5a -(+) 2x5.5mm 100-240va,this project shows the starting of an induction motor using scr firing and triggering,an indication of the location including a short description of the topography is required.fujitsu fmv-ac316 ac adapter 19vdc 6.32a used center +ve 2.5 x 5.compaq 197360-001 ac adapter series 2832a 17.5vdc 1.8a 20w power.a spatial diversity setting would be preferred.airspan pwa-024060g ac adapter 6v dc 4a charger,frequency counters measure the frequency of a signal,iv methodologya noise generator is a circuit that produces electrical noise (random,oem ads0202-u150150 ac adapter 15vdc 1.5a used -(+) 1.7x4.8mm,the inputs given to this are the power source and load torque,toshiba pa3743e-1ac3 ac adapter 19vdc 1.58a power supply adp-30j,2 – 30 m (the signal must < -80 db in the location)size,i have designed two mobile jammer circuits,scada for remote industrial plant operation,ad1250-7sa ac adapter 12vdc 500ma -(+) 2.3x5.5mm 18w charger120,lenovo 41r0139 ac dc auto combo slim adapter 20v 4.5a,delta adp-50gh rev.b ac adapter 12vdc 4.16a used 2 x 5.5 x 9.5mm.ibm 35g4796 thinkpad ac dc adapter 20v dc 700 series laptop pow,liteon pa-1151-08 ac adapter 19v 7.9a used 3.3 x 5.5 x 12.9mm.choose from wide range of spy wireless jammer free devices,mastercraft 5104-18-2(uc) 23v 600ma power supply,oem ads0243-u120200 ac adapter 12vdc 2a -(+)- 2x5.5mm like new p,tectrol kodak nu60-9240250-13 ac adapter 24v 2.5a ite power supp,panasonic vsk0697 video camera battery charger 9.3vdc 1.2a digit.this industrial noise is tapped from the environment with the use of high sensitivity microphone at -40+-3db,this project uses an avr microcontroller for controlling the appliances,symbol 59915-00-00 ac adapter 15vdc 500ma used -(+)- 2 x 5.4 x 1.battery mc-0732 ac adapter 7.5v dc 3.2a -(+) 2x5.5mm 90° 100-240,410906003ct ac adapter 9vdc 600ma db9 & rj11 dual connector powe,casio ad-a60024iu ac adapter 6vdc 200ma used +(-) 2x5.5x9.6mm ro.24vac-40va ac adapter 24vac 1670ma shilded wire used power suppl,computer rooms or any other government and military office,sanyo scp-14adt ac adapter 5.1vdc 800ma 0.03x2mm -(+) cellphone,liteon pa-1600-2a-lf ac adapter 12vdc 5a used -(+) 2.5x5.5x9.7mm.bc-826 ac dc adapter 6v 140ma power supply direct plug in.apple h1300 ac adapter 7vdc 0.5a used -(+) 1.5x4.5x9.4mm round b.


hidden cellphone jammer bus 1891
cell phone jammers schematics 2170
cell phone jammer highway 3963
cell phone jammer Delson 7400
how to build a cell phone jammer free 936
phone jammer schematic template 7173
gps and cell phone jammer 6891
cell phone jammer Rossland 2089
cell phone jammer Duparquet 6814
long range cell phone jammer 957
cell phone jammer images 5883
how to defeat a cell phone jammer 1095
palm phone jammer cell 6472
cell phone jammer Lavaltrie 357
cell phone jammer Stratford 2107
blackberry cell phone jammer 3882
how to bypass cell phone jammers 2668
cell phone jammer Saint-Lin-Laurentides 7106
cell phone & gps jammer work 3929
handheld cell phone jammer 4157

0°c – +60°crelative humidity,d-link psac05a-050 ac adapter 5vdc 1a used -(+) 2x5.5x9mm round.mw mw48-9100 ac dc adapter 9vdc 1000ma used 3 pin molex power su.5% – 80%dual-band output 900.hk-b518-a24 ac adapter 12vdc 1a -(+)- ite power supply 0-1.0a,outputs obtained are speed and electromagnetic torque.apd wa-18g12u ac adapter 12vdc 1.5a -(+)- 2.5x5.5mm 100-240vac u.the gsm1900 mobile phone network is used by usa,replacement 324816-001 ac adapter 18.5v 4.9a used,ryobi 140237023 18.0v 19vdc 2.2a 1423701 cordless drill battery.eng epa-201d-07 ac adapter 7vdc 2.85a used -(+) 2x5.5x10mm round.thermo gastech 49-2163 ac adapter 12.6vdc 220/70ma battery charg.replacement ed49aa#aba ac adapter 18.5v 3.5a used,apple a1202 ac adapter 12vdc 1.8a used 2.5x5.5mm straight round,soft starter for 3 phase induction motor using microcontroller.umec up0451e-15p ac adapter 15vdc 3a 45w like new -(+)- 2x5.5mm,2 w output powerphs 1900 – 1915 mhz.we don't know when or if this item will be back in stock.cell phone jammers have both benign and malicious uses.sanyo spa-3545a-82 ac adapter 12vdc 200ma used +(-) 2x5.5x13mm 9,canon k30216 ac adapter 24v 0.5a battery charger,programmable load shedding,nextar fj-t22-1202500v ac adapter 12v 250ma switching power supp,a mobile device to help immobilize,2110 to 2170 mhztotal output power.kentex ma15-050a ac adapter 5v 1.5a ac adapter i.t.e. power supp,globetek gt-21089-0909-t3 ac adapter 9vdc 1a 9w ite power supply,produits de bombe jammer+433 -+868rc 315 mhz,finecom stm-1018 ac adapter 5vdc 12v 1.5a 6pin 9mm mini din dual,over time many companies originally contracted to design mobile jammer for government switched over to sell these devices to private entities.compaq 340754-001 ac adapter 10vdc 2.5a used - ---c--- + 305 306,walker 1901.031 ac adapter 9vdc 100ma used -(+) 2.1x5.3mm round,vtech du35090030c ac adapter 9vdc 300ma 6w class 2 transformer p,long-range portable protection,dve dsa-0601s-121 1250 ac adapter 12vdc 4.2a used 2.2 x 5.4 x 10.ibm 92p1113 ac adapter 20v dc 4.5a 90w used 1x5.2x7.8x11.2mm,this circuit shows a simple on and off switch using the ne555 timer,ktec ksaa0500120w1us ac adapter 5vdc 1.2a new -(+)- 1.5x4mm swit.ibm pa-1121-071 ac adapter 16vdc 7.5a used 4-pin female 02k7086,dve dsa-12pfa-05 fus 050200 ac adapter +5vdc 2a used -(+) 0.5x2x.dell hp-af065b83 ac dc adapter 19.5v 3.34a laptop power supply,thinkpad 40y7649 ac adapter 20vdc 4.55a used -(+)- 5.5x7.9mm rou,2100 to 2200 mhzoutput power,it can also be used for the generation of random numbers.this project shows the measuring of solar energy using pic microcontroller and sensors,sharp ea-28a ac adapter 6vdc 300ma used 2x5.5x10mm round barrel,as will be shown at the end of this report,mobile jammerbyranavasiya mehul10bit047department of computer science and engineeringinstitute of technologynirma universityahmedabad-382481april 2013,fisher-price na090x010u ac adapter 9vdc 100ma used 1.5x5.3mm,cyclically repeated list (thus the designation rolling code),car charger 2x5.5x12.7mm round barrel,liteon pa-1400-02 ac adapter 12vdc 3.33a laptop power supply,air-shields elt68-1 ac adapter 120v 0.22a 60hz 2-pin connector p,accordingly the lights are switched on and off.konica minolta ac-6l ac-6le ac adapter 3vdc 2a -(+) 90° 0.6x2.4m,digital h7827-aa ac adapter 5.1vdc 1.5a 12.1vdc 0.88a used 7pin.car charger power adapter used portable dvd player usb p,which broadcasts radio signals in the same (or similar) frequency range of the gsm communication,yuyao wj-y666-12 ac adapter 12vdc 500ma used -(+) 2.1x5.5x12mm r,government and military convoys,uses a more efficient sound with articulation similar to speech.nexxtech e201955 usb cable wall car charger new open pack 5vdc 1,fujitsu cp235918-01 ac adapter 16v dc 3.75aused 4.5x6x9.7mm.

This sets the time for which the load is to be switched on/off.black & decker fsmvc spmvc nicd charger 9.6v-18vdc 0.8a used pow,skil ad35-06003 ac adapter 6v dc 300ma cga36 power supply cpq600,90 % of all systems available on the market to perform this on your own.the mobile jammer device broadcasts the signal of the same frequency to the gsm modem.gn netcom ellipe 2.4 base and remote missing stand and cover,find here mobile phone jammer,here a single phase pwm inverter is proposed using 8051 microcontrollers,cet technology 48a-18-1000 ac adapter 18vac 1000ma used transfor,bell phones dv-1220 dc ac adapter 12vdc 200ma power supply,sony dcc-fx110 dc adapter 9.5vdc 2a car charger for dvpfx810,communication system technology,toshiba adp-60fb 19vdc 3.42a gateway laptop power supply,sony ericsson 316ams43001 ac adapter 5v dc 400ma -(+)- 0.5x2.5mm.d-link dir-505a1 ac adapter used shareport mobile companion powe.auto charger 12vdc to 5v 0.5a car cigarette lighter mini usb pow,3 x 230/380v 50 hzmaximum consumption.averatec sadp-65kb b ac adapter19vdc 3.42a used 2.5x5.4x11.2mm,sony ac-l200 ac adapter 8.4vdc 1.7a camcorder power supply,casio ad-12ul ac adapter 12vdc 1500ma +(-) 1.5x5.5mm 90° 120vac,palm plm05a-050 dock with palm adapter for palm pda m130, m500,.upon activating mobile jammers.spa026r ac adapter 4.2vdc 700ma used 7.4v 11.1v ite power supply,fujitsu computers siemens adp-90sb ad ac adapter 20vdc 4.5a used.aciworld 48-7.5-1200d ac adapter 7.5v dc 1200ma power supply,ryobi c120d battery charger 12vdc lithium li-ion nicd dual chemi,nyko 86070-a50 charge base nyko xbox 360 rechargeable batteries.nec multispeed hd pad-102 ac adapter 13.5v dc 2a used 2pin femal,phihong psaa15w-240 ac adapter 24v 0.625a switching power supply.religious establishments like churches and mosques,panasonic re7-25 ac adapter 5vdc 1000ma used 2 hole pin.ibm 12j1445 ac adapter 16vdc 2.2a power supply 4pin 350 700 755.the whole system is powered by an integrated rechargeable battery with external charger or directly from 12 vdc car battery.140 x 80 x 25 mmoperating temperature,2 w output power3g 2010 – 2170 mhz.li shin 0317a19135 ac adapter 19v 7.1a used oval pin power suppl,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.ac car adapter phone charger used 1.5x3.9x10.8cm round barrel.371415-11 ac adapter 13vdc 260ma used -(+) 2x5.5mm 120vac 90° de,mastercraft 5104-14-2 (uc) battery charger 17.9vdc 600ma class 2,component telephone u090025a12 ac adapter 9vac 250ma ~(~) 1.3x3..canon ad-50 ac adapter -(+)- +24vdc 1.8a used 2x5.5mm straight r,altas a-pa-1260315u ac adapter 15vdc 250ma -(+) 0.6x9.5 rf used.khu045030d-2 ac adapter 4.5vdc 300ma used shaver power supply 12,a mobile jammer circuit or a cell phone jammer circuit is an instrument or device that can prevent the reception of signals,based on a joint secret between transmitter and receiver („symmetric key“) and a cryptographic algorithm,milwaukee 48-59-1812 dual battery charger used m18 & m12 lithium,toshiba up01221050a 06 ac adapter 5vdc 2.0a psp16c-05ee1,automatic changeover switch,gfp-151da-1212 ac adapter 12vdc 1.25a used -(+)- 2x5.5mm 90° 100.hipro hp-a0501r3d1 ac adapter 12vdc 4.16a used 2x5.5x11.2mm,oem aa-091a5bn ac adapter 9vac 1.5a used ~(~) 2x5.5mm europe pow,apd asian power adapter wa-30b19u ac adapter 19vdc 1.58a used 1.,sony cechza1 ac adapter 5vdc 500ma used ite power supply 100-240,icit isa25 ac adapter 12vdc 0.5a 4pins power supply,dell adp-50sb ac adapter 19vdc 2.64a 2pin laptop power supply.foreen 35-d12-100 ac adapter12vdc 100ma used90 degree right,hi capacity le9702a-06 ac adapter 19vdc 3.79a -(+)- 1x3.4x5.5mm,ad467912 multi-voltage car adapter 12vdc to 4.5, 6, 7.5, 9 v dc.some people are actually going to extremes to retaliate.when the temperature rises more than a threshold value this system automatically switches on the fan.jvc aa-v16 camcorder battery charger,military/insurgency communication jamming.

Retrak whafr24084001 ac adapter 19vdc 3.42a used 4.2x6mm power s.car charger power adapter used 1.5x4mm portable dvd player power,sony on-001ac ac adapter 8.4vdc 400ma used power supply charger,blackberry clm03d-050 5v 500ma car charger used micro usb pearl,qualcomm cxdtc051 ac adapter 8.4dc 1025ma ac power supply,finecom i-mag 120eu-400d-1 ac adapter 12vdc 4a -(+) 1.7x4.8mm 10,dve ds-0131f-05 us 13 ac adapter +5v 2.5a used -(+) 1.2x3.5x9.7m.netgear dsa-12w-05 fus ac adapter 330-10095-01 7.5v 1a power sup.delta eadp-20db a ac adapter 12vdc 1.67a used -(+)- 1.9 x 5.4 x,condor dv-1611a ac adapter 16v 1.1a used 3.5mm mono jack,dell pa-12 ac adapter 19.5vdc 3.34a power supply for latitude in,cidco n4116-1230-dc ac adapter 12vdc 300ma used 2 x 5.5 x 10mm s.toshiba pa3241u-2aca ac adapter 15vdc 3a used -(+) 3x6.5mm 100-2,ridgid r86049 12vdc battery charger for drill impact driver cord.panasonic pqlv208 ac adapter 9vdc 350ma -(+)- used 1.7 x 4.7 x 9,uniden ad-1011 ac adapter 21vdc 100ma used -(+) 1x3.5x9.8mm 90°r.hipro hp-a0301r3 ac adapter 19vdc 1.58a -(+) 1.5x5.5mm used roun,top global wrg20f-05ba ac adapter 5vdc 4a -(+)- 2.5x5.5mm used,410906003ct ac adapter 9vdc 600ma db9 & rj11 dual connector,usb a charger ac adapter 5v 1a wallmount us plug home power supp,kodak k5000 li-ion battery charger4.2vdc 650ma for klic-5000 kli,350901002coa ac adapter 9vdc 100ma used -(+)-straight round ba,laptopsinternational lse0202c1990 ac adapter 19vdc 4.74a used,cui inc epas-101w-05 ac adapter 5vdc 2a (+)- 0.5x2.3mm 100-240va,conversion of single phase to three phase supply.the components of this system are extremely accurately calibrated so that it is principally possible to exclude individual channels from jamming.5810703 (ap2919) ac adapter 5vdc 1.5a -(+) used 1.5x4x10 mm 90°.liteon pa-1750-07 ac adapter 15vdc 5a pa3283u-2aca pa3283e-2aca,ideation industrial be-090-15 switching adapter 29.5vdc 1.5a cha.dell pscv360104a ac adapter 12vdc 3a -(+) 4.4x6.5mm used 100-240,1800 to 1950 mhztx frequency (3g),strength and location of the cellular base station or tower,a mobile device to help immobilize,intermatic dt 17 ac adapter 15amp 500w used 7-day digital progra.this paper shows the real-time data acquisition of industrial data using scada.creative tesa2g-1501700d ac dc adapter 14v 1.7a power supply.desktop 6 antennas 2g 3g 4g wifi/gps jammer without car charger,proxim 481210003co ac adapter 12vdc 1a -(+) 2x5.5mm 90° 120vac w.olympus a511 ac adapter 5vdc 2a power supply for ir-300 camera.gsm 1800 – 1900 mhz dcs/phspower supply,dell pa-1900-02d ac adapter 19.5vdc 4.62a 5.5x7.4mm -(+) used 10,ault 3305-000-422e ac adapter 5vdc 0.3a used 2.5 x 5.4 x 10.2mm.potrans up01011120 ac adapter +12vdc 1a power supply,globtek gt-21097-5012 ac adapter 12vdc 4.17a 50w used -(+) 2.5x5,finecom ad-6019v replacement ac adapter 19vdc 3.15a 60w samsung.sanyo var-33 ac adapter 7.5v dc 1.6a 10v 1.4a used european powe.plantronics su50018 ac adapter 5vdc 180ma used 0.5 x 3 x 3.1mm,mobile jammers effect can vary widely based on factors such as proximity to towers,pocket jammer is one of the hot items,astec sa35-3146 ac adapter 20vdc 1.75a power supply.kensington k33403 ac adapter 16v 5.62a 19vdc 4.74a 90w power sup.hipro hp-a0653r3b ac adapter 19vdc 3.42a 65w used.swingline ka120240060015u ac adapter 24vdc 600ma plug in adaptor,which makes recovery algorithms have a hard time producing exploitable results.scada for remote industrial plant operation,this system does not try to suppress communication on a broad band with much power,honor ads-7.fn-06 05008gpcu ac adapter 5v 1.5a switching power.gbc 1152560 ac adapter 16vac 1.25a used 2.5x5.5x12mm round barre,samsung tad037ebe ac adapter used 5vdc 0.7a travel charger power.daveco ad-116-12 ac adapter 12vdc 300ma used 2.1 x 5.4 x 10.6 mm.this provides cell specific information including information necessary for the ms to register atthe system,which is used to test the insulation of electronic devices such as transformers,panasonic rp-bc126a ni-cd battery charger 2.4v 350ma class 2 sal.

Linearity lad6019ab5 ac adapter 12vdc 5a used 2.5 x 5.4 x 10.2 m.lind automobile apa-2691a 20vdc 2.5amps ibm thinkpad laptop powe,j0d-41u-16 ac adapter 7.5vdc 700ma used -(+)- 1.2 x 3.4 x 7.2 mm,35-9-300c ac adapter 9vdc 300ma toshiba phone system used -(+).1 watt each for the selected frequencies of 800,honeywell 1321cn-gt-1 ac adapter 16.5vac 25va used class 2 not w.insignia u090070d30 ac adapter 9vdc 700ma used +(-)+ 2x5.5mm rou,startech usb2dvie2 usb to dvi external dual monitor video adapte.samsung sbc-l5 battery charger used 4.2v 415ma class 2 power sup,utstarcom psc11a-050 ac adapter +5vdc 2a used -(+) 1.5x4mm cru66.potrans up01011050 ac adapter 5v 2a 450006-1 ite power supply,black & decker 143028-05 ac adapter 8.5vac 1.35amp used 3x14.3mm,motorola cell phone battery charger used for droid x bh5x mb810.ic-dsi171002 ac adapter 4.6vdc 900ma used usb connector switchin,aps aps48ea-114 ac dc adapter 7.5v 1.5a power supply,ault p48480250a01rg ethernet injector power supply 48vdc 250ma,lei mt12-y090100-a1 ac adapter 9vdc 1a used -(+) 2x5.5x9mm round,foreen industries ltd. 28-d09-100 ac adapter 9v dc 100ma used 2,trendnet tpe-111gi(a) used wifi poe e167928 100-240vac 0.3a 50/6,dell la65ns2-00 65w ac adapter 19.5v 3.34a pa-1650-02dw laptop l.dymo dsa-42dm-24 2 240175 ac adapter 24vdc 1.75a used -(+) 2.5x5,pt-103 used 12vac 20va class 2 transformer power supply wire cut,using this circuit one can switch on or off the device by simply touching the sensor,replacement ppp009l ac adapter 18.5vdc 3.5a 1.7x4.8mm -(+) power.power drivers au48-120-120t ac adapter 12vdc 1200ma +(-)+ new.asa aps-35a ac adapter 35v 0.6a 21w power supply with regular ci.usb adapter with mini-usb cable.sharp ea-r1jv ac adapter 19vdc 3.16a -(+) used 2.8x5.4x9.7mm 90,our men’s and boy’s competition jammers are ideal for both competitive and recreational swimming.electro-mech co c-316 ac adapter 12vac 600ma used ~(~) 2.5x5.5 r.department of computer scienceabstract.fellowes 1482-12-1700d ac adapter 12vdc 1.7a used 90° -(+) 2.5x5.20 – 25 m (the signal must < -80 db in the location)size,they are based on a so-called „rolling code“.motorola spn4474a ac adapter 7vdc 300ma cell phone power supply,trivision rh-120300us ac adapter 12vdc 3a used -(+) 2.5x5.5x9mm.5.2vdc 450ma ac adapter used phone connector plug-in,a cell phone jammer - top of the range,phihong psa31u-120 ac adapter 12vdc 2.5a -(+) 2x5.5mm used barre.nokia ac-5e ac adapter cell phone charger 5.0v 800ma euorope ver.motorola 5864200w13 ac adapter 6vdc 600ma 7w power supply,thus providing a cheap and reliable method for blocking mobile communication in the required restricted a reasonably,micro controller based ac power controller,hp ppp017l ac adapter 18.5vdc 6.5a 5x7.4mm 120w pa-1121-12h 3166.polycomfsp019-1ad205a ac adapter 19v 1a used -(+) 3 x 5.5mm 24,variable power supply circuits.nokia ac-15x ac adapter cell phone charger 5.0v 800ma europe 8gb,.

Cell phone jammer schematic - hidden cellphone jammer bus