AFE031: AFE031: NB-PLC FCC AFE031

Hi Alex, 

We have the following NB-PLC integrated controller, namely AFE030, AFE031 and AFE032. AFE031 and AFE030 are very similar, where AFE031 can drive slightly higher current than AFE030, but both parts have the same Fill Power BW, which is limited to 300kHz.  

If you are interested in wider NB-PLC Application, AFE032 will be the option,  AFE032 has the Full Power BW that covers the full operating range of NB-PLC. Above 500kHz, it is considered as BB-PLC (Broadband-PLC). 

Alex Sanchez said:

1. Why is the 9khz to 150khz range not listed for FCC in many publications (including FCC)? Is it because it is allocated to other use (e.g., utility vendors)? This range of frequencies is also allocated for CENELEC (band A/B/C/D) compliant devices, but isn't CENELEC only applicable to Europe? Or can I have a device for sale in the US where it will operate in any of the CENELEC bands (9khz to 150khz range) and have it be FCC compliant/certified?

Although FCC NB-PLC is defined up to 490kHz, certain communication protocols are only operated in certain ranges of the bandwidth (less interferences from other communication protocols). For instance, G3-FCC is typically operated between 150kHz -490kHz, ARIB STD (Japan) protocol is operated between 35kHz to 420kHz, FCC-Low is operated from 35kHz to 125kHz, and CENELEC A-D bands are operated between 35kHz - 148kHz. Since all these communication protocols are transmitted and received through AC or DC powerlines, ideally only one type of communication protocols will be preferred to operate in the particular powerline application. If different communication protocols have to co-exist in the same powerline, Tx/Rx data transmission signals have to operate without the communication interferences from each other, which are difficult to do. Bandpass filters may have to be used in order isolate from different frequency ranges, and I am not aware of anyone is doing that in the powerline communication. The division of different frequency bandwidths in NB-PLC applications are similar to radio and wireless communications, where UHF, VHF, HF, LF and SHF are regulated by national spectrum management authorities for different uses and applications. 

CENELEC PLC protocol is European communication standard, but it is used elsewhere in other application, including in the USA. For instance, Cenelec-C is popular in solar-farm and DC/AC converter for solar energy selector (due to its simplicity, but the data rate of the protocol is limited). 

Certainly, you can select a frequency range for your PLC communication. If you want to operate from 9kHz to 150kHz frequency range, you may select FCC-Low communication frequency spectrum, which is from 35kHz to 125kHz. CENELEC protocol is typically narrower frequency spectrum. If you have a need for a particular PLC communication, you have to follow the defined frequency spectrum communication protocol. Yes, you have to certify to the select communication protocol standard, which the communication has to follow standard. Not only the frequency spectrum is regulated, the power emission level, industry standards, safety requirements are all have to take into consideration, because all these factors are regulated by different government agency; the certification and compliances are required. 

Alex Sanchez said:

2. What is meant by "consumer use, no protocol"? does that mean I am free to come up with my own communication protocol and still be able to get it certified under FCC in those frequencies, or does it need to be a standardized protocol such as Prime/G3, etc. (assuming OFDM)?

The term "consumer use, no protocol" , usually it means that the PLC system does not adhere to any standardized communication protocol or standard, and may be a proprietary or custom solution that is designed for a specific consumer or residential application. This can provide flexibility in terms of customization and integration into specific systems, but it may also lack interoperability with other PLC systems or devices that follow standardized protocols.

I am not an expert about your "free to come up with my own communication protocol". In PLC, you are transmitting or receiving an equivalent "0" or "1" digital data packet. You can group the different numbers of bits and define your proprietary protocol,  but you still have to follow some kind of regulatory standards, if you want to transmit or receive the communication in distance. For instance, you have to adhere the powerline safety standards, EMI mitigation, Electromagnetic Emissions, compliance with environmental regulation, power quality consideration etc.. These are regulated by government and state agencies, even regulated by your power providers to some extent, including your local fire department for the safety rescue operation (some installation and operation are regulated by National Electrical Safety Code (NESC) by law). 

Alex Sanchez said:

3. Assuming I really need to be >150khz for FCC, then can't my device operate in the 150khz to 200khz range for example and still be certified under FCC?

If this is a commercial PLC product, I believe that the system has to be certified by a PLC standards for a particular communication protocol. 

Alex Sanchez said:

4. Would the AFE031 + F28002x have the capability and/or processing power to handle an OFDM based protocol in this range (150khz to 200khz)? I see that for the B-FSK application example, it was estimated at ~11% utilization using 28379 running at 200Mhz. Since the F28002x runs at 100Mhz, can it still handle the task?

AFE031 is capable to Tx or Rx at the operating frequency, but I am not sure that F28002x has the capacity to handle high through rate in OFDM protocol. This is a question to our C2000 DSP team. BFSK is relative simply communication protocol to modulate and demodulated via F28002x processor. OFDM on other hand are much more complex in modulating and demodulating data of the communication protocols. Please send me "friendship" request via E2E, and we can exchange some additional information in private, if you want to know more about the PLC application. 

Best,

Raymond