ELECTROMAGNETIC COMPATIBILITY (EMC)

Electromagnetic compatibility is a key issue in determining the deployment of BPL.  Working with the customer KOHL will insure that the BPL power system is checked for ingress interference to the selected BPL equipment.  KOHL is in the vanguard in developing measurement capabilities to determine BPL system compliance with FCC regulations with regard to EMC.  Visiting installed BPL systems KOHL has assessed RF radiation patterns and FCC compliance.  KOHL has conducted test range experiments to assess the efficacy of FCC testing procedures, and can assist the vendor and customer in dealing with potential BPL interference and susceptibility issues.  KOHL has IEEE Fellows and ARRL member consultants who have established a positive dialog with the ARRL Laboratory regarding potential interference issues between BPL operations and amateur radio licensees.

 HIGH-FREQUENCY, RADIO FREQUENCY INTERFERENCE (RFI)

 Perhaps the major obstacle to ubiquitous deployment of BPL is High-Frequency (HF) Radio Frequency Interference (RFI).  The deployment of BPL can create radio frequency interference which is detrimental to users of these high frequencies, which consist of the amateur HAM radio operators, emergency and public safety frequency and short wave channel users and others.  RFI is not only a technical challenge, but also of great political significance, as the licensed HAM radio frequency users are among the most affected by, and the most vocal in, their criticism of BPL.  A utility contemplating BPL must evaluate and solve issues of HF-RF interference.  There have been reports of pilot programs having been severely curtailed or abandoned because of lack of understanding of the potential to solve the interference problem.

KOHL is in the forefront in developing the interference testing methods.  These were developed for a large long distance carrier during BPL trials and proved invaluable in detecting and mitigating RFI.  In addition we posses proprietary, state-of-the-art test equipment for use in both lab and field trials.  KOHL is prepared to manage each aspect of the customer’s RFI testing needs.
   Our HF-RFI test bed is used to conduct assessments of high-speed data distribution systems.  Using proprietary mobile field-measurement methods, site assessments of potential harmful interference from vendors’ systems are made.  Any performance-degrading susceptibilities to interference are quantified, and mitigation steps are instituted.
    Baseline field measurements should be taken initially, to document existing radio interference sources prior to a BPL trial.  Making use of its proprietary, portable HF transmitting antenna KOHL simulates known amounts of interference throughout the HF spectrum to BPL trial system.  This is used to determine the system susceptibility to realistic neighboring exposures.
    Using proprietary full-sized “reference” transmitting antennas at various HF frequencies to radiate known amounts of interference power, KOHL is able to evaluate different interference measurements at a distance.  Employing both the FCC-prescribed, and alternative KOHL devised testing methods, KOHL has determined that there is harmful interference potential, even in a range currently acceptable under the FCC test approach.
    KOHL has successfully used its measurement system and apparatus to suggest enhancements to customer’s BPL systems and to identify the sources of interference affecting reliability and potentially limiting data throughput capacities.

 REGULATORY CONSULTING

Winding its way through the maze of regulatory organizations is a challenge for even the most sophisticated customer.  KOHL consults with customers on FCC regulations relevant to BPL and rulemaking activity.  KOHL has provided input for FCC filings intended to influence policy with regard to BPL.  KOHL has researched and prepared a summary of FCC licensed, and NTIA-authorized band use in the frequency range considered for BPL applications (2-80 MHz).

 KOHL maintains a rapport and dialog with the various stake holder regulatory bodies including the National Telecommunications and Information Administration (NTIA), which regulates federal government spectrum use.