TaCT is a communication and tracking technology, which addresses the billions of devices requiring location, medium bandwidth, long range and a communication capability. TaCT combines a low power LoRa® network with native geo-location capability, where any IoT tag or sensor on the network can be geo-located.
The TaCT network uses LoRa modulation at 2.4GHz and emulates a LoRaWAN® network. All the usual server and security features of a LoRaWAN network are implemented in the TaCT system. Implementation at 2.4GHz removes the transmit duty cycle limitation of many systems operating in the 868/915MHz ISM band, allowing significantly more bandwidth per tag/sensor.
Deploying a TaCT system with geo-location is easy and cost-efficient. The TacT system typically includes the following components.
Anchors are required for systems that implement geo-location. The anchors are placed at known positions in the area to be monitored and are used to provide round trip time of flight ranging (RTToF) information from themselves and tags/sensors in the system. The ranging data is sent to the application server, which uses the ranges of the tag from several anchors to compute the location of the tag.
TaCT geo-location calculates the position of tags in the system by performing round trip time of flight (RTToF) radio exchanges between fixed position anchors and the tags. TaCT location accuracy is in the range of 1-3m, depending on system configuration and operating environment.
TaCT requires between four and eight anchors in a group to perform location, and the anchors should fully enclose the area of interest. Anchors are assigned to groups, and up to eight anchor groups can report through a single Gateway. Multiple gateways can be deployed, with each new gateway adding an additional eight anchor groups of capacity. To perform location of a tag, every anchor in the group performs a two-way time of flight ranging operation with the tag. The resulting times of flight are transmitted to the location server via the Gateway. Once the distance between the tag and all the anchors in the group is known, the location server calculates the location and makes a GPS coordinate position available to the User Application.
In this diagram, you can see a cluster of fixed anchors, with the Tag representing ANY number of tags, or sensors being located.
The physical distance between anchors, gateways and tags is determined mostly by the operating environment. Outdoors in line of sight, location is possible with greater than 500m between components. With a 500m effective range, large areas can be covered with small quantities of fixed infrastructure, making the system very cost efficient. Indoors the range is dependent on building construction and materials. Please contact us for an estimate, based on your particular use case.
Accuracy depends on the number of anchors with good line of sight to the tag. Placing anchors, so that four or more anchors have line of sight, will produce the best result. Many indoor location projects do not require 1-2m accuracy. For instance, locating hospital or industrial equipment only needs room level, or 4m localisation accuracy. Once in the locale, it is easy enough to find the equipment. Reducing fixed infrastructure requirements will significantly reduce installation and operation costs. The TaCT localisation algorithm has been engineered to produce good location accuracy with reduced levels of fixed infrastructure, often producing good results with only one or two fixed anchors per room. Please contact us for a demonstration of what can be achieved.
The TaCT system is capable of real-time location of a small number of tags, scheduled, or on-demand location of large numbers of tags. Mixing and matching of location methods is supported, where a small number of tags can be located in real-time, while a much larger number of tags can also be located on a scheduled or on-demand basis. Location policies are used to determine the frequency of location of every tag in the system. Location policy and radio usage has an influence on battery life. The capacities in the table below are for the minimum possible configuration of one anchor group. The capacities can be multiplied by the number of anchor groups deployed. The schedule frequency of once per hour was chosen by way of example, and the frequency can be higher or lower with a commensurate change in the number of tags located.
Minimum system location capacity for a single gateway deployment
|Policy||Capacity (up to)||Typical Battery Life||Note|
|Real Time||60 locations per minute||Weeks-Months||8 locations per minute per tag maximum|
|Scheduled||3600 Tags||Months-Years||One location per tag, per hour scheduled|
Maximum system capacity for a single gateway deployment
|Policy||Capacity (up to)||Typical Battery Life||Note|
|Real Time||480 locations per minute||Weeks-Months||8 locations per minute per tag maximum|
|Scheduled||28,800 Tags||Months-Years||One location per tag, per hour scheduled|
The indoor location accuracy of the system is between 1 and 3m depending on operating environment and the density of anchors used. The TaCT location software uses a unique technique for reducing the effect of multipath reception on the RTToF ranging results. The LoRa modulation allows the ranging signals to penetrate farther into buildings than other low power radio location systems. This combination of low power, long range and multipath reduction makes TaCT more cost effective to deploy because of the lower number of anchors required for a given area. TaCT does not require finger printing of the operating environment like BTLE and WiFi systems, so is quicker to install and does not require regular maintenance to keep the system accurate.
TaCT is a globally available IoT solution, operating in the 2.4GHz ISM band. TaCT has an operating range of up to a few km, with link channel bandwidths of up to 200kbps. The TaCT network is capable of coexisting with WiFi and BTLE devices sharing the same radio space, enabling new IoT, M2M, smart-home, sensor networks, and industrial automation applications. The technology allows private single, or multi-user networks to connect to multiple end applications, with either local, or remote network and application servers.
The TaCT network employs a star topology, end devices to communicate with gateways in the network. TaCT gateways act as transparent bridges, relaying messages between end-devices and a central network server, which is ideal for cloud deployment.
The TaCT IoT system uses an emulation of the LoRaWAN stack running in the 2.4GHz ISM band. The system combines the known advantages of LoRa, namely, long range, low power and robust signalling, with much higher data throughput and a native ranging and location technology. The data rate is similar to Zigbee with longer range. The table summarises the key attributes of popular IoT technologies.
|Voice||Y (up to 300m)||N||Y (2-10m)||N||N|
**pricing for NB-IoT sim varies considerably by country, provider and data plan. It may be necessary to switch provider during the lifetime of the product to control costs.
TaCT-Voice is a voice communication system, compatible with the TaCT network. Conversations can be held either on a one to one basis, or multicast to a group of participants. Voice is a unique feature of the TaCT network.
The TaCT evaluation kit includes everything required for you to make an evaluation of the TaCT platform. The evaluation kit includes the software for the join, network and applications server running on a Raspberry Pi, a TaCT gateway, eight TaCT anchors and four tags.