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], short-range wireless chips ship approximately 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]
According to ECC Rec. 70-03, there are several annexes which encapsulate specific usage patterns, maximum emission power and duty cycle requirements.
| Frequency | Band | Notes | |
|---|---|---|---|
| Annex 1. Non-specific short-range devices | |||
| 6765–6795 kHz | |||
| 13.553–13.567 MHz | RFID | ||
| 26.957–27.283 MHz | Citizens' Band | ||
| 40.660–40.700 MHz | |||
| 138.20–138.45 MHz | |||
| 433.050–434.790 MHz | LPD433 (70-centimeter band); also an Amateur Radio band | ||
| 863–870 MHz | SRD860 | ||
| 915–928 MHz | SRD860 | ||
| 2400.0–2483.5 MHz | 13-centimeter band Heavily used by Wi-Fi; also an Amateur Radio band (Up to 2450 MHz) | ||
| 5725–5875 MHz | 5-centimeter band
| ||
| 24.00–24.25 GHz | 1.2-centimeter band
| ||
| 61.0–61.5 GHz | |||
| 122–123 GHz | 2.5-millimeter band
| ||
| 244–246 GHz | 1-millimeter 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 | Wi-Fi, Bluetooth, etc. | ||
| 57–66 GHz | 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 | |||
| 63–64 GHz | Vehicle to vehicle and road to vehicle systems | ||
| 76–77 GHz | Vehicle radar and infrastructure radar systems | ||
| 21.65–26.65 GHz | Automotive short range radars (SRR) (marketed until July 2013) | ||
| 77–81 GHz | Automotive short range radars (SRR) | ||
| 24.050–24.075 GHz 24.075–24.150 GHz 24.150–24.250 GHz | Vehicle radars | ||
| Annex 6. Radiodetermination applications | |||
| 2400.0–2483.5 | |||
| 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 | |||
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).
| 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)
, 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., 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]