A short-range device (SRD), described by
ECC Recommendation 70-03, is a
radio-frequency
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the ...
transmitter
In electronics and telecommunications, a radio transmitter or just transmitter (often abbreviated as XMTR or TX in technical documents) is an electronic device which produces radio waves with an antenna (radio), antenna with the purpose of sig ...
device used in
telecommunication
Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of ...
that has little capability of causing
harmful interference to other radio equipment.
Short-range devices are low-power transmitters, typically limited to 25–100 mW
effective radiated power (ERP) or less, depending on the frequency band, which limits their useful range to a few hundred meters, which do not require licenses to use.
Short-range
wireless
Wireless communication (or just wireless, when the context allows) is the transfer of information (''telecommunication'') between two or more points without the use of an electrical conductor, optical fiber or other continuous guided transm ...
technologies include
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 Wireless LAN, local area networking of devices and Internet access, allowing nearby digital devices to exchange data by ...
,
NearLink,
near-field communication (NFC),
LPWAN,
ultra-wideband (UWB) and
IEEE 802.15.4. They are implemented by chips
fabricated as
RF CMOS integrated circuit
An integrated circuit (IC), also known as a microchip or simply chip, is a set of electronic circuits, consisting of various electronic components (such as transistors, resistors, and capacitors) and their interconnections. These components a ...
(
RF circuit).
, short-range wireless chips ship approximately billion units annually, with Bluetooth accounting for over 55% of shipments and Wi-Fi around 35% of shipments.
Applications for short-range wireless devices include
power meters and other
remote instrumentation,
RFID applications,
radio-controlled models,
fire
Fire is the rapid oxidation of a fuel in the exothermic chemical process of combustion, releasing heat, light, and various reaction Product (chemistry), products.
Flames, the most visible portion of the fire, are produced in the combustion re ...
, security and social alarms, vehicle radars, wireless microphones and earphones, traffic signs and signals (including control signals), remote
garage door opener
A garage door opener is a motorized device that opens and closes a garage door controlled by switches on the garage wall. Most also include a handheld radio remote control carried by the owner, which can be used to open and close the door from ...
s and
car keys, barcode readers, motion detectors, and many others.
The
European Commission
The European Commission (EC) is the primary Executive (government), executive arm of the European Union (EU). It operates as a cabinet government, with a number of European Commissioner, members of the Commission (directorial system, informall ...
mandates through
CEPT and
ETSI the allocation of several device bands for these purposes, restricts the parameters of their use, and provides guidelines for avoiding radio interference.
[ CEPT/ERCbr> REC 70-03]
(22 August 2011)[ ETSI EN 300 220-1 v2.3.1 (2010-02). Table 5.]
Frequency bands
According to ECC Rec. 70-03, there are several annexes which encapsulate specific usage patterns, maximum emission power and duty cycle requirements.
SRD860
In Europe, 863 to 870 MHz band has been allocated for license-free operation using
FHSS,
DSSS, or analog modulation with either a transmission
duty cycle of 0.1%, 1% or 10% depending on the band, or Listen Before Talk (LBT) with
Adaptive Frequency Agility (AFA).
Although this band falls under the Short Range Device umbrella, it is being used in Low-Power Wide-Area Network (
LPWAN)
wireless telecommunication networks, designed to allow long-range communications at a low
bit rate among
things (connected objects).
(* = as of 1 January 2018)
, unrestricted voice communications are allowed in the 869.7-870.0 MHz band with channel spacing of 25 kHz or less and maximum power output of 5 mW ERP.
SRD860 handheld transceivers were briefly available in mid 2000s, however they did not offer dual-band compatibility with
PMR446 and LPD433 bands. , they have been put off-market.
From January 2018, the four RFID frequencies are also available for data networks, with a power up to 500 mW and a bandwidth of 200 kHz. The center frequencies are: 865.7, 866.3, 866.9 and 867.5 MHz. Specific restrictions on usage apply, such as a low duty cycle, LBT (listen before transmit) and APC (adaptive power control).
See also
*
DASH7
References
External links
*
*
*
* {{cite web, title=SRD/MG - Short Range Devices, url=http://www.cept.org/ecc/groups/ecc/wg-fm/srdmg, website=CEPT.org, accessdate=24 November 2017
Radio electronics