A new technology for indoor, outdoor and mobile location based applications
ZuluTime technology offers a new approach to solving location based business problems where other approaches have only produced partial solutions. This means that our technology works where GPS and other techniques can’t — indoors, in urban canyons, and even in mobile ad hoc networks. ZuluTime refines the timing and spatial calibration of the network, allowing it to construct precise space/time values through proprietary algorithms.
Most current location based business applications use GPS, “Time Difference of Arrival” (TDOA), “Relative Signal Strength Indicator” (RSSI), or a combination of these techniques, all of which deliver partial solutions to the business problems.
GPS techniques require an unobstructed line of site to multiple satellites for reliable positioning. This means it is highly unreliable indoors and in urban canyons where satellite Line of Site (LOS) is blocked or limited.
TDOA and RSSI techniques require a fixed reference network of transmitters of known location. RSSI requires detailed site surveys and relatively stable environments to account for signal distortion. This means that they provide variable resolution, varying reliability and the inability to work in ad hoc environments where all transceivers are on the move.
ZuluTime’s revolutionary approach enables it to cost-effectively deploy across wireless networks while augmenting and/or replacing existing techniques. ZuluTime enabled location aware wireless networks can offer solutions that are:
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*Note: TDOA methodologies here describe Time of Arrival, Time Difference of Arrival, Angle of Arrival, Observed Time Difference and similar.
Patent Pending TNFE Technology
Unlike conventional positioning technologies that rely upon different methods of trilateration using reference satellites and fixed transmitters, ZuluTime’s proprietary Temporal Network Field Equation (TNFE) technology is actually part of the “wireless cloud” of the communications network itself encompassing data from all of the transceivers in the network. Since it is interlaced in the communications signaling methodology generally at the network layer, it becomes an ever-present data point leveraged by both nodes and clients alike. ZuluTime’s software can be implemented on any digital wireless system, including Wi-Fi, mobile telephony and Software Defined Radio (SDR). Additionally, ZuluTime technology can also be implemented in hardware when a manufacturer prefers a proprietary advantage.
Technology Comparisons
GPS
GPS may be global, but its not ubiquitous.
Twenty-four GPS satellites are operational at any one time and orbit the Earth at more that 11,000 nautical miles in six orbital planes. This orbital structure provides continuous, global coverage that enables users to determine their three dimensional position at any point on the globe as long as they have clear line of sight to a minimum number of satellites.
The fact is that GPS fails or is unreliable in many business applications. Application reliability demands that quality positioning data is provided to the end user when the user wants it. For a delivery truck driving through a city’s urban canyon, or a driver equipped with an in-car navigation system exiting a tunnel, at 60mph, if the “Time-To-First-Fix” for the satellites takes more than a minute then the system fails.
ZuluTime excels in dynamic environments, indoors and urban canyons, exactly those places where GPS is simply too unreliable for continuous “need to know now” navigation and tracking systems.
TDOA
Like GPS, Time Difference of Arrival (TDOA) technologies, such as TOA, AOA and OTD measure differences in the time of arrival (and sometimes angles) of messages from transmitters at known locations in the network to calculate the position of a mobile transceiver. This approach is limited by the visibility of each moving transceiver to a minimum number of fixed transmitters necessary to calculate its position. Unfortunately both static and dynamic RF propagation and distortion exist in many environments, as well as mulitpath distortion resulting from reflected and interfering signals. Any of these effects can be fatal to accurate positioning.
In contrast, ZuluTime’s TNFE technology works in both static and mobile environments. It is also much less susceptible to static and dynamic RF field and multipath distortions.
RSSI
Like the TDOA approaches described above, Received Signal Strength Indicator (RSSI) technologies measure differences in the strength of RF signals arriving from transmitters at known locations in the network to calculate the position of a mobile transceiver. This approach is also limited by the visibility of each transceiver to the minimum number of fixed transmitters to calculate its position. Here again, both static and dynamic distortion of RF propagation in the environment and multipath distortion arising from reflected and interfering signals diminishes the system’s performance. RF modeling of the environment is required, this is expensive and inefficient.
ZuluTime excels in providing continuous location information on wireless networks whether you're in urban canyons, indoors or on the move. 
