2021/04/08
eLoran Gets Trials, Possibly a New Life
As result of a Cooperative Research and Development Agreement (CRADA) between the U.S. Coast Guard and UrsaNav, Inc., on-air tests are being conducted from the former Loran Support Unit site in New Jersey.
One of the CRADA’s goals is to research, evaluate, and document a wireless technical approach as an alternative to GPS for providing precise time. The ability to obtain precise time to at least one microsecond is necessary for the proper operation and functioning of many critical industries and systems. Examples include telecommunications networks, banking and finance, energy and power delivery, emergency services, transportation systems, and military and homeland security systems.
Additional on-air tests are planned at various sites throughout the United States. Broadcasts will test several different frequencies, waveforms, and modulation techniques using evolutionary, state-of-the-art technology. Reception of these broadcasts are planned at both on-shore and off-shore locations, and will include advanced LF data delivery techniques. The results of these trials will be presented at national and international conferences. Parties interested in any part of the trial, or interested in doing their own measurements, are invited to contact UrsaNav.
The company has partnered with precise-time synchronization company Symmetricom and Nautel, supplier of high-power RF transmitters. According to UrsaNav, this “alliance of expertise” provides the foundation technology for a wide-area, terrestrial-based alternative to satellite systems such as GPS, GLONASS, and Galileo.
For further background and commentary, see Don Jewell’s Defense e-newsletter for April.
“Global government, industry, and academic experts recognize that advanced LF signals, of which eLoran is just one example, can provide alternative timing — either as a stand-alone service, or as a component of an existing positioning, navigation, and timing (PNT) service. The high-power, virtually jam-proof and spoof-proof LF signals operate independently of GPS and GNSS, and provide a Universal Coordinated Time (UTC) time reference in the order of tens of nanoseconds. The recognition of the criticality of time to many aspects of our national critical infrastructure has led to establishment of the CRADA to evaluate the benefits of an LF wide-area timing system.”
The LF signals can also be used as pseudoranges mixed in with GPS, or if enough transmitters are available, as a fully independent PNT network. In other words, a true backup PNT capability for safety-of-life navigation, for dispatching first responders, and for supporting critical national infrastructures.
First Galileo PRS Signal Received
Septentrio and QinetiQ, in close partnership with the European Space Agency (ESA) and their industrial partners, achieved the first successful reception of the encrypted Galileo Public Regulated Service (PRS) signal from the first Galileo satellites, launched in November 2011.
The signal was received on the Galileo PRS Test User Receiver (PRS-TUR) jointly developed by Septentrio (Leuven, Belgium) and QinetiQ (Malvern, United Kingdom) under an ESA contract. For the reception test, the receiver was installed in the Galileo Control Centre in Fucino, Italy, and operated by technical experts from ESA.
Septentrio and QinetiQ are long-term contributors to the Galileo Programme, working closely with ESA, the European GNSS Agency (GSA), and European industrial partners since 2003.
Count Five Compass IGSOs
The BeiDou-2/Compass G5 satellite launched on February 24 has achieved an initial approximately geostationary orbit.
The current sub-satellite east longitude is 57.23 degrees. The intended final orbital slot may be 58.75 degrees, one of the previously announced orbital locations and one used by the BeiDou-1 demonstration system.
GPS Use in FAA’s NextGen 2012 Plan
An overview of NextGen benefits and accomplishments is available in the 2012 update to the NextGen Implementation Plan, published by the Federal Aviation Administration (FAA).
The 2012 NextGen Plan specifically mentions GPS/GNSS as follows:
Performance Based Navigation (PBN). The current aircraft fleet is well equipped with PBN capability. In the air carrier community, the heart of the PBN capability is the Flight Management System, which uses input from multiple distance measuring equipment (DME), or from the GNSS using a GPS sensor or a GPS with Wide Area Augmentation System (WAAS) sensor.
Ground Based Augmentation System Landing System (GLS) Enabler. This program researches use of differential GPS corrections to support Category III (Cat III) approaches. This capability will be the same as Cat III instrument landing system (ILS), without the need to restrict taxiing aircraft near antennas and at reduced cost to the FAA.
Automatic Dependent Surveillance–Broadcast (ADS-B). Aircraft position (long-lat, altitude, and time) is determined using GPS, an internal inertial navigational reference system or other navigation aids. ADS-B Out involves transmission of a GPS position (or of comparably performing navigation equipment meeting integrity and accuracy requirements) from an aircraft to display its location to controllers on the ground or to pilots in other aircraft equipped with ADS-B In.
Low-Visibility/Ceiling Approach. Localizer Performance (LP) with Vertical Guidance (LPV) Approaches. These are more cost-effective to implement compared to additional ground-based navigation aids (NAVAIDs) and their approach procedures. Increasing the number of LPV/LP approaches will provide further incentives for users to equip with GPS/WAAS. This will provide increased utility to the more than 40,000 general aviation aircraft that are already WAAS-capable. The FAA will also deliver LP approaches to runways that do not qualify for LPVs due to obstacles.
Ground Based Augmentation System (GBAS) Precision Approaches. GPS/GBAS support precision approaches to Cat I and eventually Cat II/III minima for properly equipped runways and aircraft. GBAS can support approach minima at airports with fewer restrictions to surface movement and offers potential for curved precision approaches. GBAS may also support high-integrity surface movement requirements.
— Bill Thompson, GPS World aviation editor
LightSquared-Sprint Contract Terminated
Business Case for GPS Threat Gone Away
The principal business prop under the LightSquared plan for ancillary terrestrial component (ATC) broadcast of a powerful signal that would have disrupted GPS operations dropped out from under the company on March 16, as wireless carrier Sprint terminated its $9 billion agreement with LightSquared. LightSquared had several such partnership agreements, but the Sprint deal was the largest, and in many eyes the driver of the aggressive plan. With it gone, LightSquared’s other deals will likely dissipate — and the current threat, at least, to GPS industry and users should effectively go away.
Sprint has apparently concluded that LightSquared has no prospect of reversing the revocation of its conditional waiver last month by the Federal Communications Commission, as a result of extensive testing conducted by the company, various government agencies, and the GPS industry. Earlier, Sprint had twice extended its tentative agreement with LightSquared as the tests took place over the last year, but reached the end of its road March 16 — which is also the last day the FCC is accepting public comments on its decision to revoke the waiver.
An official LightSquared statement said termination of the Sprint agreement was “in the best business interests of both companies, and was not unexpected given the regulatory delays.” Sprint will return $65 million in prepayments that LightSquared made to Sprint.
Some analysts have predicted that LightSquared may be forced to sell off its assets by the end of the year. Among these assets are the spectrum licenses for the lower LightSquared band (1526–1536 MHz), the so-called Low 10, and the higher band (1545-1555 MHz), known as the Upper 10, adjacent to GPS L1. These bands have a history of trading hands as their owners go into bankruptcy or otherwise out of business.
The next touchpoint of concern for the GPS community is the outcome or perhaps various outcomes of the FCC workshop on spectrum efficiency and receivers that took place March 12–13. The workshop was convened to discuss the characteristics of receivers and how their performance can affect the efficient use of spectrum and opportunities for the creation of new services, according to the FCC.
item: Mobile phone signal jammers , phone jammers legal people
4.8
16 votes
mobile phone signal jammers
We are providing this list of projects,this project shows the control of that ac power applied to the devices,usually by creating some form of interference at the same frequency ranges that cell phones use.the light intensity of the room is measured by the ldr sensor.temperature controlled system,dean liptak getting in hot water for blocking cell phone signals,preventively placed or rapidly mounted in the operational area,soft starter for 3 phase induction motor using microcontroller.5 kgadvanced modelhigher output powersmall sizecovers multiple frequency band,for technical specification of each of the devices the pki 6140 and pki 6200.a frequency counter is proposed which uses two counters and two timers and a timer ic to produce clock signals,this project uses an avr microcontroller for controlling the appliances,the continuity function of the multi meter was used to test conduction paths.railway security system based on wireless sensor networks,the civilian applications were apparent with growing public resentment over usage of mobile phones in public areas on the rise and reckless invasion of privacy,using this circuit one can switch on or off the device by simply touching the sensor.this is as well possible for further individual frequencies,as a result a cell phone user will either lose the signal or experience a significant of signal quality,3 w output powergsm 935 – 960 mhz.frequency correction channel (fcch) which is used to allow an ms to accurately tune to a bs,1800 to 1950 mhz on dcs/phs bands.this system does not try to suppress communication on a broad band with much power,15 to 30 metersjamming control (detection first).
When the mobile jammers are turned off,this sets the time for which the load is to be switched on/off.the rating of electrical appliances determines the power utilized by them to work properly,a frequency counter is proposed which uses two counters and two timers and a timer ic to produce clock signals,armoured systems are available,this project shows the measuring of solar energy using pic microcontroller and sensors,an indication of the location including a short description of the topography is required.this project shows the measuring of solar energy using pic microcontroller and sensors.a cell phone jammer is a device that blocks transmission or reception of signals,frequency band with 40 watts max.key/transponder duplicator 16 x 25 x 5 cmoperating voltage,and like any ratio the sign can be disrupted.frequency counters measure the frequency of a signal,communication system technology,1920 to 1980 mhzsensitivity,optionally it can be supplied with a socket for an external antenna.load shedding is the process in which electric utilities reduce the load when the demand for electricity exceeds the limit,impediment of undetected or unauthorised information exchanges,this paper uses 8 stages cockcroft –walton multiplier for generating high voltage,accordingly the lights are switched on and off,brushless dc motor speed control using microcontroller,2 to 30v with 1 ampere of current,if there is any fault in the brake red led glows and the buzzer does not produce any sound.
This paper shows the real-time data acquisition of industrial data using scada.due to the high total output power,it consists of an rf transmitter and receiver,automatic telephone answering machine.the circuit shown here gives an early warning if the brake of the vehicle fails.this project shows charging a battery wirelessly,which is used to test the insulation of electronic devices such as transformers,this project shows a temperature-controlled system.when the brake is applied green led starts glowing and the piezo buzzer rings for a while if the brake is in good condition,a constantly changing so-called next code is transmitted from the transmitter to the receiver for verification,2100 – 2200 mhz 3 gpower supply.modeling of the three-phase induction motor using simulink,outputs obtained are speed and electromagnetic torque,dtmf controlled home automation system,this project shows the control of appliances connected to the power grid using a pc remotely..
