What is LoRa?

LoRa (short for long range) is a spread spectrum modulation technique derived from chirp spread spectrum (CSS) technology. Semtech’s LoRa devices and wireless radio frequency technology (LoRa Technology) is a long range, low power wireless platform that has become the de facto technology for Internet of Things (IoT) networks worldwide. LoRa Technology enables smart IoT applications that solve some of the biggest challenges facing our planet: energy management, natural resource reduction, pollution control, infrastructure efficiency, disaster prevention, and more. Semtech’s LoRa Technology has amassed over 600 known uses cases for smart cities, smart homes and buildings, smart agriculture, smart metering, smart supply chain and logistics, and more. With over 50 million devices connected to networks in 95 countries and growing, LoRa Technology is the DNA of IoT, creating a Smarter Planet.


Unlicensed spectrum in EU

According to ERC RECOMMENDATION 70-03 (Tromsø 1997 and subsequent amendments) and Radio Equipment Directive 2014/53/EU there are following unlicensed frequencies available in EU


Frequency Band

Power /

Magnetic Field

Spectrum access and mitigation requirement

Channel spacing

ECC/ERC Decision


Notes


a

6765-6795 kHz

42 dBµA/m at 10m

No requirement

No spacing



b

13.553-13.567 MHz

42 dBµA/m at 10m

No requirement

No spacing



c

26.957-27.283 MHz

42 dBµA/m at 10m 10 mW e.r.p

No requirement

No spacing



d

40.660-40.700 MHz

10 mW e.r.p.

No requirement

No spacing



e

138.20-138.45 MHz

10 mW e.r.p.

< 1.0 % duty cycle
(note 1)

No spacing



f

433.050-434.790 MHz

(note 4)

10 mW e.r.p.

< 10 % duty cycle
(note 1)

No spacing



f1

433.050-434.790 MHz

(note 4bis)

1 mW e.r.p.

 -13 dBm/10 kHz

No requirement

No spacing


Power density limited to -13 dBm/10 kHz for wideband modulation with a bandwidth greater than 250 kHz

f2

434.040-434.790 MHz

(note 4bis)

10 mW e.r.p.

No requirement

Up to 25 kHz



g

863-870 MHz

(note 3, 4 and 6)

≤ 25 mW e.r.p. 

≤ 0.1% duty cycle
or LBT

(note 1 and 5)

≤ 100 kHz

for 47 or more channels

(note 2)

 

FHSS modulation

 

≤ 25 mW e.r.p.

(note 6)

Power density :

- 4.5 dBm/100 kHz

(note 7)

≤ 0.1% duty cycle
or LBT+AFA

(note 1, 5 and 6)

No spacing

 

DSSS and other wideband modulation other than FHSS

 

≤ 25 mW e.r.p.

≤ 0.1% duty cycle
or LBT+AFA

(note 1 and 5)

≤ 100 kHz,

for 1 or more channels

modulation bandwith

≤ 300 kHz

(note 2)

 

Narrow /wide-band modulation


g1

868.000-868.600 MHz

(note 4)

≤ 25 mW e.r.p.

≤ 1% duty cycle
or LBT+AFA

(note 1)


No spacing,

for 1 or more channels

(note 2)


Narrow / wide-band modulation.

No channel spacing, however the whole stated frequency band may be used

g2

868.700-869.200 MHz

(note 4)

≤ 25 mW e.r.p.

≤ 0.1% duty cycle
or LBT+AFA

(note 1)

No spacing,

for 1 or more channels

(note 2)


Narrow / wide-band modulation.

No channel spacing, however the whole stated frequency band may be used

g3

869.400-869.650 MHz


≤ 500 mW e.r.p.

≤ 10% duty cycle
or LBT+AFA

(note 1)

25 kHz

(for 1 or more channels)


Narrow / wide-band modulation

The whole stated frequency band may be used  as 1 channel for high speed data transmission

g4

869.700-870.000 MHz

(note 4bis)

≤ 5 mW e.r.p.

≤ 25 mW e.r.p.

No requirement

up to 1% duty cycle
or LBT+AFA

(note 1)

No spacing

(for 1 or more channels)


Narrow / wide-band modulation.

No channel spacing, however the whole stated frequency band may be used

h

2400.0-2483.5 MHz

10 mW e.i.r.p.

No requirement

No spacing



i

5725-5875 MHz

25 mW e.i.r.p.

No requirement

No spacing



j

24.00-24.25 GHz

100 mW e.i.r.p.

No requirement

No spacing



k

61.0-61.5 GHz

100 mW e.i.r.p.

No requirement

No spacing



l

122-123 GHz

100 mW e.i.r.p.

No requirement

No spacing



m

244-246 GHz

100 mW e.i.r.p.

No requirement

No spacing



n

3.1-4.8 GHz

6 – 9 GHz

*

*

*

ECC/DEC/(06)04

ECC/DEC/(06)12

Generic UWB regulation

* See detailed requirements in related ECC Decisions

Note 1:     When either a duty cycle, Listen Before Talk (LBT) or equivalent technique applies then it shall not be user dependent/adjustable and shall be guaranteed

                by appropriate technical means.

                For LBT devices without Adaptive Frequency Agility (AFA), or equivalent techniques, the duty cycle limit applies.

                For any type of frequency agile device the duty cycle limit applies to the total transmission unless LBT or equivalent technique is used.

Note 2:     The preferred channel spacing is 100 kHz allowing for a subdivision into 50 kHz or 25 kHz.

Note 3:     Sub-bands for alarms are excluded (see ERC/REC 70-03 Annex 7).

Note 4:     Audio and video applications are allowed provided that a digital modulation method is used with a max. bandwidth of 300 kHz.

                Analogue and digital voice applications are allowed with a max. bandwidth ≤ 25 kHz.

                In sub-band 863-865 MHz voice and audio conditions of Annexes 10 and 13 of ERC/REC 70 – 03 apply respectively.

Note 4bis: Audio and video applications are excluded. Analogue or digital voice applications are allowed with a max. bandwidth ≤ 25 kHz and with spectrum access technique such as LBT or equivalent. The transmitter shall include a power output sensor controlling the transmitter to a maximum transmit period of 1 minute for each transmission

Note 5:     Duty cycle may be increased to 1% if the band is limited to 865-868 MHz.

Note 6:     For other wide-band modulation than FHSS and DSSS with a bandwidth of 200 kHz to 3 MHz, duty cycle can be increased to 1% if the band is limited to 865-868 MHz and power to ≤10 mW e.r.p.

Note 7:     The power density can be increased to +6.2 dBm/100 kHz and -0.8 dBm/100 kHz, if the band of operation is limited to 865-868 MHz and 865-870 MHz

                respectively.

LoRa Frequencies in EU

In EU frequencies reserved for LoRa are between 868 and 870 Mhz. That falls under band in the table which is regulated by stantard ETSI EN 330 220. The problem in this band is that transmitter must obey duty-cycle limitations. When transmitting there are two important factors:

  • Bandwidth (125KHz, 250Khz) defines how many symbols are transferred each second
  • Spreading factor, how may symbols are needed for one piece of information. This is in order of 2^N (N - spreading factor)

Following table show how long TX is active for different configurations. Firs row represents 125Khz, second represents 250Khz

LoRa and LoRaWan

LoRa is physicall layer (ISO/OSI layer 1) LoRaWan occupies higher layers. The topic of this knowledge base is only LoRa, because simple point-to-point link can be formed using this technology with custom MAC and upper layers. Since all modules on market are constructed using Semtech SX1276 module or equivalent, datasheet is appened to this page and contains a lot of useful information.

Sources