Starkley Laboratories submitted a petition for rulemaking asking the FCC to amend Section 15.247(a) of the rules to allow the use of devices with a minimum bandwidth of 100 kHz rather than the currently allowed 500 kHz minimum in the 902-928 MHz band. Starkley would maintain the current 8 dBm/3 kHz spectral power density limit specified in Section 15.247(c) of the rules.
As the power density isn't increasing, the narrower bandwidth operation should not cause any additional interference. And also, as Starkley pointed out, would allow more efficient use of the spectrum.
Starkley wants to use the spectrum for digital audio equipped assistive listening devices (ALDs). Its proposed revision to the rules would allow the use of ALDs to send digital audio information to hearing aid wearers for the purpose of improving the signal-to-noise ratio of audio information presented in a classrooms, auditoriums, airport terminals, and similar public venues.
The FCC Public Notice (DA 09-673) said that such an amendment would enable the operation of wireless devices for transmitting public service announcements and alarms, and also for hearing assistance devices to enhance the quality of life for the hearing disabled.
Hearing assistance devices currently have one megahertz of spectrum centered on 217 MHz. Starkley Laboratories said this allocation is limited to one-way communication and is allocated in 5-50 kHz channels, which makes control, wireless programming, and bi-directional communication impossible and is insufficient for supporting digital high fidelity information.
The 902-928 MHz spectrum is shared with a number of federal, non-federal, licensed and unlicensed spectrum users. Starkley Laboratories' requested operation could impact on both licensed and unlicensed users.
In addition to the request for the rules modification to allow narrower bandwidth operation under Part 15.247(a), Starkley Laboratories has also filed a request for a waiver of Part 15.247(a)(2) for unlicensed operation of systems using digital modulation in the 902-928 MHz band.
The FCC Office of Engineering and Technology is requesting comment on both proposals. See Public Notice DA 09-676 for information on the waiver request and how to file comments in that proceeding.
