Short-range device

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A short-range device (SRD), described by ECC Recommendation 70-03, is a radio-frequency transmitter device used in telecommunication 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 technologies include Bluetooth, Wi-Fi, 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 (RF circuit).[1][2] (As of 2009), short-range wireless chips ship approximately 1.7 billion units annually, with Bluetooth accounting for over 55% of shipments and Wi-Fi around 35% of shipments.[1]

Applications for short-range wireless devices include power meters and other remote instrumentation, RFID applications, radio-controlled models, fire, security and social alarms, vehicle radars, wireless microphones and earphones, traffic signs and signals (including control signals), remote garage door openers and car keys, barcode readers, motion detectors, and many others.

The European Commission 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.[3][4][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.

Frequency allocation in Rec. 70-03
Frequency Band Notes
Annex 1. Non-specific short-range devices
6765–6795 kHz ISM
13.553–13.567 MHz ISM RFID
26.957–27.283 MHz ISM Citizens' Band
40.660–40.700 MHz ISM
138.20–138.45 MHz
433.050–434.790 MHz ISM LPD433 (70-centimeter band); also an Amateur Radio band
863–870 MHz ISM SRD860
915–928 MHz ISM SRD860
2400.0–2483.5 MHz ISM 13-centimeter band Heavily used by Wi-Fi; also an Amateur Radio band (Up to 2450 MHz)
5725–5875 MHz ISM 5-centimeter band; also an Amateur Radio band (Up to 5850 MHz)
24.00–24.25 GHz ISM 1.2-centimeter band; also an Amateur Radio band
61.0–61.5 GHz ISM
122–123 GHz ISM 2.5-millimeter band; also an Amateur Radio band
244–246 GHz ISM 1-millimeter band; also an Amateur Radio band
3.1–4.8 THz
6–9 THz
Annex 2. Tracking, tracing and data acquisition
456.9–457.1 kHz Detection of avalanche victims
169.4–169.475 MHz Remote meter reading
169.4–169.475 MHz Asset tracking and tracing
Annex 3. Wideband data transmission systems
2400.0–2483.5 MHz ISM Wi-Fi, Bluetooth, etc.
57–66 GHz V WiGig, WirelessHD, etc.
Annex 4. Railway applications
2446–2454 MHz Automatic vehicle identification systems for railways
27.090–27.100 MHz Balise tele-powering and down-link (train to ground) systems
984–7484 kHz Balise up-link (ground to train) systems
7.3–23.0 MHz Loop up-link (ground to train) systems
Annex 5. Road transport and traffic telematics (RTTT)
5795–5805 MHz
5805-5815 MHz
C
63–64 GHz V Vehicle to vehicle and road to vehicle systems
76–77 GHz W Vehicle radar and infrastructure radar systems
21.65–26.65 GHz K Automotive short range radars (SRR) (marketed until July 2013)
77–81 GHz W Automotive short range radars (SRR)
24.050–24.075 GHz
24.075–24.150 GHz
24.150–24.250 GHz
ISM Vehicle radars
Annex 6. Radiodetermination applications
2400.0–2483.5 ISM
9200–9500 MHz
9500–9975 MHz
10.5–10.6 GHz
13.4–14.0 GHz
24.05–24.25 GHz ISM
4.5–7.0 GHz Tank level probing radar (TLPR)
8.5–10.6 GHz Tank level probing radar (TLPR)
24.05–27.00 GHz Tank level probing radar (TLPR)
57–64 GHz Tank level probing radar (TLPR)
75–85 GHz Tank level probing radar (TLPR)
17.1–17.3 GHz Ground-based synthetic aperture radar
Annex 7. Alarms
868.6–868.7 MHz
869.250–869.300 MHz
869.650–869.700 MHz
869.200–869.250 MHz
869.300–869.400 MHz
169.4750–169.4875 MHz Social alarms (exclusive use)
169.5875–169.6000 MHz Social alarms (exclusive use)
Annex 8. Model control
26.995, 27.045,
27.095, 27.145,
27.195 MHz
34.995–35.225 MHz Only for flying models
40.665, 40.675,
40.685, 40.695 MHz
Annex 9. Inductive applications
Annex 10. Radio microphone applications including aids for the hearing impaired
29.7–47.0 MHz except 30.3–30.5 MHz, 32.15–32.45 MHz and 41.015–47.00 MHz (harmonised military bands)
173.965–174.015 Aids for the hearing impaired
863–865 MHz Individual licence required
470–786 MHz Individual licence required
786–789 MHz Individual licence required
823–826 MHz
826–832 MHz
Individual licence required
1785–1795 MHz
1795–1800 MHz
Individual licence required
169.4000–169.4750 MHz Aids for the hearing impaired. Individual licence may be required
169.4875–169.5875 MHz Aids for the hearing impaired. Individual licence may be required
Annex 11. Radio frequency identification applications
2446–2454 MHz
2446–2454 MHz
865.0–865.6 MHz
865.6–867.6 MHz
867.6–868.0 MHz
Annex 12. Active medical implants and their associated peripherals
Annex 13. Wireless audio applications
863–865 MHz
864.8–865.0
SRD860
1795–1800 MHz
87.5–108.0 MHz FM

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).[3][4] 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).

Frequency Duty cycle Channel spacing ERP
863.0–865.0 MHz 100% (wireless audio) 10 mW
863.0–865.6 MHz 0.1% or LBT+AFA 25 mW
863.0–868.0 MHz * 25 mW wideband up to 1 MHz (data only)
865.0–868.0 MHz 1% or LBT+AFA 25 mW
865.0–868.0 MHz * 0.1% or LBT+AFA 4 frequencies 2 W (RFID only)
865.0–868.0 MHz * 10% (access points), 2.5% (other devices) 4 frequencies 500 mW (data only, power control required)
868.0–868.6 MHz 1% or LBT+AFA 25 mW
868.6–868.7 MHz 1% (alarms) 25 kHz 10 mW
868.7–869.2 MHz 0.1% or LBT+AFA 25 mW
869.2–869.25 MHz 0.1% (social alarms) 25 kHz 10 mW
869.25–869.3 MHz 0.1% (alarms) 25 kHz 10 mW
869.3–869.4 MHz 1% (alarms) 25 kHz 10 mW
869.4–869.65 MHz 10% or LBT+AFA 25 kHz 500 mW
869.65–869.7 MHz 10% (alarms) 25 kHz 25 mW
869.7–870.0 MHz 100% (voice communication) 5 mW
1% or LBT+AFA 25 mW

(* = as of 1 January 2018)

(As of December 2011), 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.[6][7][8]

SRD860 handheld transceivers were briefly available in mid 2000s, however they did not offer dual-band compatibility with PMR446 and LPD433 bands. (As of 2012), 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).[9]

See also

References

External links




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