ANT is a proprietary (but open access)

multicast In computer networking, multicast is group communication where data transmission is addressed to a group of destination computers simultaneously. Multicast can be one-to-many or many-to-many distribution. Multicast should not be confused with ...

wireless sensor network Wireless sensor networks (WSNs) refer to networks of spatially dispersed and dedicated sensors that monitor and record the physical conditions of the environment and forward the collected data to a central location. WSNs can measure environmental c ...

technology designed and marketed by ANT Wireless (a division of

Garmin Garmin Ltd. (shortened to Garmin, stylized as GARMIN, and formerly known as ProNav) is an American, Swiss-domiciled multinational technology company founded in 1989 by Gary Burrell and Min Kao in Lenexa, Kansas, United States, with headquarte ...

Canada). It provides

personal area network A personal area network (PAN) is a computer network for interconnecting electronic devices within an individual person's workspace. A PAN provides data transmission among devices such as computers, smartphones, tablets and personal digital ass ...

s (PANs), primarily for

activity tracker An activity tracker, also known as a fitness tracker, is a device or application for monitoring and tracking fitness-related metrics such as distance walked or run, calorie consumption, and in some cases heartbeat. It is a type of wearable comp ...

s. ANT was introduced by Dynastream Innovations in 2003, followed by the low-power standard ANT+ in 2004, before Dynastream was bought by Garmin in 2006. ANT defines a wireless communications

protocol stack The protocol stack or network stack is an implementation of a computer networking protocol suite or protocol family. Some of these terms are used interchangeably but strictly speaking, the ''suite'' is the definition of the communication protoco ...

that enables hardware operating in the 2.4

GHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...

ISM band The ISM radio bands are portions of the radio spectrum reserved internationally for industrial, scientific and medical (ISM) purposes, excluding applications in telecommunications. Examples of applications for the use of radio frequency (RF) ener ...

to communicate by establishing standard rules for co-existence, data representation, signalling,

authentication Authentication (from ''authentikos'', "real, genuine", from αὐθέντης ''authentes'', "author") is the act of proving an assertion, such as the identity of a computer system user. In contrast with identification, the act of indicatin ...

, and

error detection In information theory and coding theory with applications in computer science and telecommunication, error detection and correction (EDAC) or error control are techniques that enable reliable delivery of digital data over unreliable communi ...

. It is conceptually similar to Bluetooth low energy, but is oriented towards use with sensors. the ANT website lists almost 200 brands using ANT technology.

Overview

ANT-powered nodes are capable of acting as sources or sinks within a

concurrently. This means the nodes can act as transmitters, receivers, or transceivers to route traffic to other nodes. In addition, every node is capable of determining when to transmit based on the activity of its neighbors.

Technical information

ANT can be configured to spend long periods in a low-power sleep mode (consuming of the order of microamps of current), wake up briefly to communicate (when consumption rises to a peak of 22mA (at -5 dB) during reception and 13.5mA (at -5 dB) during transmission) and return to sleep mode. Average current consumption for low message rates is less than 60 microamps on some devices. Each ANT channel consists of one or more transmitting nodes and one or more receiving nodes, depending on the network topology. Any node can transmit or receive, so the channels are bi-directional. ANT accommodates three types of messaging: broadcast, acknowledged, and burst. Broadcast is a one-way communication from one node to another (or many). The receiving node(s) transmit no acknowledgment, but the receiving node may still send messages back to the transmitting node. This technique is suited to sensor applications and is the most economical method of operation. Acknowledged messaging confirms receipt of data packets. The transmitter is informed of success or failure, although there are no retransmissions. This technique is suited to control applications. ANT can also be used for burst messaging; this is a multi-message transmission technique using the full data

bandwidth Bandwidth commonly refers to: * Bandwidth (signal processing) or ''analog bandwidth'', ''frequency bandwidth'', or ''radio bandwidth'', a measure of the width of a frequency range * Bandwidth (computing), the rate of data transfer, bit rate or thr ...

and running to completion. The receiving node acknowledges receipt and informs of corrupted packets that the transmitter then re-sends. The packets are sequence numbered for traceability. This technique is suited to data block transfer where the integrity of the data is paramount.

Comparison to other protocols

ANT was designed for low bit-rate and low power sensor networks, in a manner conceptually similar to (but not compatible with) Bluetooth low energy. This is in contrast with normal

Bluetooth Bluetooth is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is limi ...

, which was designed for relatively high bit-rate applications such as streaming sound for low power headsets. ANT uses adaptive isochronous transmission to allow many ANT devices to communicate concurrently without interference from one another, unlike Bluetooth LE, which supports an unlimited number of nodes through

scatternet A scatternet is a type of ad hoc computer network consisting of two or more piconets. The terms "scatternet" and "piconet" are typically applied to Bluetooth wireless technology. Description A ''piconet'' is the type of connection that is forme ...

s and broadcasting between devices.

Interference immunity

Bluetooth,

Wi-Fi Wi-Fi () is a family of wireless network protocols, based on the IEEE 802.11 family of standards, which are commonly used for local area networking of devices and Internet access, allowing nearby digital devices to exchange data by radio wav ...

, and

ZigBee Zigbee is an IEEE 802.15.4-based specification for a suite of high-level communication protocols used to create personal area networks with small, low-power digital radios, such as for home automation, medical device data collection, and o ...

employ Direct Sequence Spread Spectrum (DSSS) and

Frequency-Hopping Spread Spectrum Frequency-hopping spread spectrum (FHSS) is a method of transmitting radio signals by rapidly changing the carrier frequency among many distinct frequencies occupying a large spectral band. The changes are controlled by a code known to both tr ...

(FHSS) schemes respectively to maintain the

integrity Integrity is the practice of being honest and showing a consistent and uncompromising adherence to strong moral and ethical principles and values. In ethics, integrity is regarded as the honesty and truthfulness or accuracy of one's actions. In ...

of the wireless link. ANT uses an adaptive

isochronous A sequence of events is isochronous if the events occur regularly, or at equal time intervals. The term ''isochronous'' is used in several technical contexts, but usually refers to the primary subject maintaining a constant period or interval ( ...

network technology to ensure coexistence with other ANT devices. This scheme provides the ability for each transmission to occur in an interference free time slot within the defined frequency band. The radio transmits for less than 150 µs per message, allowing a single channel to be divided into hundreds of time slots. The ANT messaging period (the time between each node transmitting its data) determines how many time slots are available.

ANT+

ANT+, introduced in 2004 as "the first ultra low power wireless standard", is an interoperability function that can be added to the base ANT protocol. This standardization allows for the networking of nearby ANT+ devices to facilitate the open collection and interpretation of sensor data. For example, ANT+ enabled fitness monitoring devices such as heart rate monitors, pedometers, speed monitors, and weight scales can all work together to assemble and track performance metrics. ANT+ is designed and maintained by the ANT+ Alliance which is managed by ANT Wireless, a division of Dynastream Innovations owned by

. ANT+ is used in Garmin's line of fitness monitoring equipment. It is also used by Garmin's Chirp, a

geocaching Geocaching is an outdoor recreational activity, in which participants use a Global Positioning System (GPS) receiver or mobile device and other navigational techniques to hide and seek containers, called "geocaches" or "caches", at specific l ...

device, for logging and alerting nearby participants. ANT+ devices require certification from the ANT+ Alliance to ensure compliance with standard device profiles. Each device profile has an icon which may be used to visually match interoperable devices sharing the same device profiles. The ANT+ specification is publicly available. At DEF CON 2019, hacker Brad Dixon demonstrated a tool to modify ANT+ data transmitted through

USB Universal Serial Bus (USB) is an industry standard that establishes specifications for cables, connectors and protocols for connection, communication and power supply (interfacing) between computers, peripherals and other computers. A broad ...

for cheating in virtual cycling.

References

External links

*
Open-source communication tool (antpm)
{{Wireless Sensor Network Wireless sensor network