MESH4G™ Technology

MESH4G™ technology is the most widely deployed and powers the largest mobile mesh networks in the world. MESH4G™-Enabled Architecture technology leverages patented and proven routing techniques originally developed for battlefield communications. By pushing intelligence and decision making to the edge of the network, high performance and scalable broadband networks can be built at very low cost.

Basics to Mesh Networking

Mesh networking is typically implemented in two basic modes: infrastructure and/or client meshing. To gain the maximum benefit that meshing can offer, both modes need to be supported simultaneously and seamlessly in a single network.

 

Infrastructure Meshing

Infrastructure meshing creates wireless backhaul mesh among wired Access Points and Wireless Routers. This reduces system backhaul costs while increasing network coverage and reliability.

 

Client Meshing

Client meshing enables wireless peer-to-peer networks to form between and among client devices (for example, end users) and does not require any network infrastructure to be present. In this case, clients can hop through each other to reach other clients in the network.

MESH4G™ Scalable Routing

At the heart of MESH4G™ ad-hoc networking technology is a highly efficient routing protocol designed specifically for use in Multi-Hopping™ wireless MESH4G™ networks – the MESH4G™ Scalable Routing protocol. This protocol is designed to work efficiently with or without centralized wireless infrastructure equipment (i.e. wired APs or stations), which enables nodes to seamlessly transition between “infrastructure-enhanced” and client-based “peer-to-peer” networks.

Scalable Routing technology enables dynamic, self-forming, self-healing, Multi-Hopping™ routing between participating nodes in an ad-hoc (mesh) network. This protocol is a hybrid routing approach that leverages proactive and reactive routing techniques via situation-aware networking. With this methodology , network topology dynamics, local RF conditions and degree of node mobility influence the routing metrics used on a moment by moment basis.

The Scalable Routing protocol is self-optimizing and delivers ultra-fast route convergence for mobile or RF hostile networks, while minimizing overhead on a per node and system wide basis. This unique technique reduces the flooding overhead and latency usually associated with the route discovery process of classical reactive protocols, as well as the high routing overhead usually associated with classical proactive protocols. The situation-aware routing algorithms used in this protocol greatly enhances the scalability of the network, while supporting high mobility in real world, wide area networks. In addition, the algorithms used have been demonstrated to be free of routing loops in all topology and network conditions.

Scalable Routing technology leverages a real-time assessment of connectivity and other environmental factors to determine routes between nodes as well as end-to-end paths through the network. It learns of these conditions via a set of metrics supplied by Adaptive Transmission protocol services (see below). This continuous assessment of network and RF conditions also helps it accomplish “make before break” routing, resulting in smooth handoffs, seamless connectivity, and reliable communications for high speed mobile networks. Strong interaction with Adaptive Transmission protocol services also enables the Saclable Routing protocol to characterise the “bi-directionality” of a link. That is, the extent to which a wireless link can support symmetric data rates to and from a pair of nodes. The ability to characterise and assess asymmetric links is critical for real world wireless routing.

Adaptive Transmission Protocol Service

Many possible environmental conditions can interfere with data transmitted wirelessly, particularly broadband data in high speed mobility situations. Multipath, shadowing, fast fading, and interference (both intentional and unintentional) can all cause excessive packet loss at the receiver.

To deal with these conditions, the transmitter will be instructed to back down its data rate for a period of time. However, these RF conditions can appear on a highly dynamic basis. If the data rate is decreased for longer than the condition exists, link reliability may be satisfactory, but throughput is not maximized. If the data rate is raised too quickly while the condition continues, the resulting packet loss can also lead to poor data throughput. The purpose of Adaptive Transmission protocol services is to enable the Scalable Routing protocol to balance the requirements of a reliable transmission whilst assuring the highest data throughput rate possible on a packet by packet basis.

In addition to providing link quality metrics, these services inform the Scalable Routing protocol of the impact that transmit power level has on network capacity for a given link. For example, the high transmit power required by a particular link may create interference and uses channel resources (i.e. spectrum) unnecessarily. Adaptive Transmission protocol services provide multiple physical layer statistics to the Scalable Routing protocol, which then becomes power-aware. At the same time, these services actively determine the fastest data rate that can be achieved on a packet by packet basis for each link.

Quad-Channel Military Radio (QCMR)

QCMR radio technology uses Direct Sequence Spread Spectrum (DSSS) and operates in the ISM II 2.4 GHz bands. This radio is specifically designed and optimized for wide area, mobile mesh networking systems. It incorporates a multi-channel MAC (3 data channels and one control channel) that enables support for a higher density of meshed users than single channel MAC radios. Position/location technology is built-in to the QCMR radio and does not rely on GPS.

 

QCMR and the 802.11 Radio Protocol Compared

The question is often asked, "What is the difference between 802.11 and QCMR radio platforms?" The simple answer is that the radios are designed for different applications. The QCMR radio exists to address markets that 802.11 cannot - specifically wide area & mobile data applications.

 

802.11 Background

The 802.11 radio protocol was designed to provide a cost effective alternative to the piece of LAN cable between the wall and the user’s computer. When 802.11 was being designed, it was expected that the radio would be deployed indoors and the computer would remain relatively immobile. Subsequently, 802.11 was designed to provide very high data rates over short distances to stationary computers using a very low cost, low powered radio.

However, 802.11 has very little immunity from either self-induced or externally generated interference. These and other trade-offs were made to reduce the cost of 802.11. Unfortunately, it also worked to limit radio performance in such a way as to render 802.11 unusable in wide area mobile applications. Current 802.11 technology provides an excellent short range, fixed wireless solution as long as the required level of performance can be supported within the restrictions of these inherent limitations.

 

QCMR Background

On the other hand, QMCR broadband radios are optimized specifically for wide area, mobile ad-hoc networking applications. With origins based on military specifications and requirements, it was designed to provide reliable communications under the most demanding battlefield conditions.

QMCR radios benefit from having a high performance RF front end that includes capabilities such as multi-tap rake receivers (commonly found in cell phones) and real-time equalization algorithms to compensate for the rapidly varying RF environments typically encountered in real-world mobile environments.

QMCR mobile broadband radios also incorporate increased error correction capability- again necessary for wide area and mobile communications. While this does limit the overall maximum burst data rate to 6 Mbps, it also improves the effective range for mobile users. Rather than the typical maximum of 300 feet for line of sight (LOS) transmissions for 802.11, QMCR radios have a range of 1 mile LOS. Both of these ranges are typical when using omni-direction antennas.

Enhanced interference rejection and signal sensitivity allow QMCR-based networks to provide multi-megabit data rates at speeds up to 250 mph, whereas 802.11 drops the radio link at about 20 mph under real world Multipath conditions.

QMCR also offers additional capabilities not found in the 802.11 standard. One very significant feature is a position location capability that provides better than 10 meter accuracy in a high speed mobile environment which is not reliant on GPS.

Its multi-channel MAC and Phy are optimized to meet the scalability and reliability required in mission critical mesh networks. RF challenges encountered in wide area mobile networks such as Doppler shifting, rapid Raleigh fading and Multipath are handled efficiently by the QMCR radio. QMCR solutions have been successfully deployed in Public Safety, transportation and Homeland Security mobile data networks.

MESH4G™ Positioning System

MESH4G™ Positioning System technology offers 3-D position, location and tracking capabilities without the use of GPS Satellites.

 

Fast and Accurate

Positioning System technology leverages patented position location and determination methods built into our QCMR radio, as well as sophisticated, but CPU efficient, heuristic processing. The core elements of this technology can be added to other radio platforms. Positioning System-enhanced products allow you to determine your own position or the position of any other user without the use of GPS satellites. Position location information, accurate to within +/- 10 meters, is generated in less than one second at mobility speeds of up to 200 mph!

 

No GPS Required

Since MESH4G™ Positioning System doesn’t rely on satellites, it works in both exterior and interior locations where GPS will not. Position location is determined utilizing sophisticated time of flight and triangulation information by using other devices in the network as reference points. These features are available in both infrastructure and ad-hoc peer-to-peer networks. Unique and powerful applications for military, public safety, telematics and m-commerce applications can be built with MESH4G™ products and technologies.

 

Works Where GPS Doesn’t

The MESH4G™ Positioning System has been proven to perform in buildings, even collapsed structures. GPS technology can’t begin match this level of performance. Precise location within a structure can be displayed via absolute positioning (i.e. geo-referenced coordinates) or relative positioning (distance from other nodes or users).

 

Supports Network and Client Based Applications

The position location of all clients and infrastructure nodes can be monitored in real-time from a network operations center. Clients can also instantly determine their own location. All position location data is presented in industry standard format - so Positioning System data (absolute location information) works seamlessly with any GPS based application.