NRF52832 BLE Certification under ETSI EN 300 328

[simao.pinheiro]

Hello,

My company recently developed a product based on your NRF52832. After some research and direct contact with some labs, we came to the conclusion that we have to test our product under the european directive EN 300 328. The lab that we are in contact with then asked us to fill annex E.2 from the directive.

www.etsi.org/.../en_300328v020101p.pdf

As we don't have an RF engineer on our team we are experiencing serious diffilcuties in doing just that. There are lots of information available but we don't seem to be able to find direct answers to the questions present in the form. Worse than that is the absurd amount of contradictory information that we bumped into.

With that being said, We kindly ask if you could help us with this matter, either by filling out the form or by work us through the document step by step.

Thanks in advance

[bjorn-spockeli]

No, you should qualify the nRF51822 with the S130 the same way as the nRF52832 and the S132, i.e. non-adaptive equipment without FHSS. This because a BLE device will advertise in sequence on 3 fixed channels in the 2400-2483 MHz band. Therefore, a BLE device should be qualified as a "system using digital modulation techniques". FCC 15.247 (2) and not a Frequency Hopping System, i.e. you do not have to provide the testing facility with frequency dwell times, channel order etc.

This is described in the Bluetooth Low Power Regulatory Aspects Whitepaper, found here.

[haveltec]

Hi Bjørn, thanks for the infos!

[Andrzej]

Dear Bjorn,

As in new ETSI 300 328 v .2.1.1 in 4.2.1 there are defined two categories FHSS and other.

This document no longer defines what FHSS is (there was a definition in last version and BLE didin't meet those requiremnets), what's more BLE Core document in 1.1 says

Like the BR/EDR radio, the LE radio operates in the unlicensed 2.4 GHz ISM
band. The LE system employs a frequency hopping transceiver to combat
interference and fading and provides many FHSS carriers.

Our question is how should we fill the form: ANEX E if we use NRF52840 with SoftDevice 140. 

And Can You provide the source for the information that BLE should be qualified as "system using digital modulation techniques"?

[bjorn-spockeli]

This is stated in the Bluetooth Low Power Regulatory Aspects Whitepaper, found here. BLE does not meet the FHSS requirements due to the limit number of channels used for advertisment, i.e. 3 channels. 

5.2.1 FCC

FCC classifies Bluetooth BR/EDR as a FHSS system; however, Bluetooth LE does not fulfill these requirements*. Instead, FCC classifies Bluetooth LE as a system using digital modulation techniques. 15.247(a)(2): Systems using digital modulation techniques may operate in the 902 - 928 MHz, 2400 - 2483.5 MHz, and 5725 - 5850 MHz bands. The minimum 6 dB bandwidth shall be at least 500 kHz.

*)Frequency hopping spread spectrum systems (FHSS) in the 2400-2483.5 MHz are in FCC 15.247(1) (iii) required to a) use at least 15 channels and b) when hopping, the transmission also must comply with a 0.4 second/channel maximum dwell time. 

5.2.2 ETSI

ETSI classifies Bluetooth BR/EDR as an FHSS system; however, Bluetooth LE does not fulfill the FHSS requirements in clause 4.2.1. Instead, ETSI classifies Bluetooth LE as a system using DSSS (direct-sequence spread spectrum) modulation. 

§ 4.2.2: For the purposes of the present document, other forms of modulation which do not satisfy the constraints of the specification given in clause 4.2.1, shall be considered equivalent to DSSS modulation. Systems using these other forms of modulation shall be considered equivalent to DSSS systems and shall be tested according to the requirements for DSSS modulation.

[Andrzej]

Dear Bjorn,

I'm aware of Bluetooth Low Power Regulatory Aspects Whitepaper but it refers to 4.2.1, which in new version 2.1.1 looks like:

4.2.1 Modulation types
The present document defines two categories of Wide Band Data Transmission equipment:
• Equipment using Frequency Hopping Spread Spectrum (FHSS) modulation.
• Equipment using other types of wide band modulation (e.g. DSSS, OFDM, etc.).
The manufacturer can categorize the equipment to any of the above as long as the equipment complies with the
corresponding requirements defined in either clause 4.3.1 or clause 4.3.2. This is part of the product information to be
declared by the manufacturer. See clause 5.4.1.

So there is no requirement for minimum 15 channels for advertising...