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802.18 Study Group 1 A Regulatory Framework for Use of TV Channels by Part 15 Devices. Lower DFS threshold to -110 dBm Indoors/outdoor operation: 0 dBm, DFS, TPC, IPD required. Rural Outdoor Only Operation:
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802.18 Study Group 1A Regulatory Framework for Use of TV Channels by Part 15 Devices John Notor, Cadence Design Systems, Inc.
Lower DFS threshold to -110 dBm Indoors/outdoor operation: 0 dBm, DFS, TPC, IPD required. Rural Outdoor Only Operation: 6 Watts for outdoor operation in environments < 25% TV broadcast incumbent occupancy, 2 unused guard channels (i.e. no broadcast incumbent) on each side. 25 Watts for outdoor operation with < 10% TV broadcast incumbent occupancy, 2 unused guard channels on each side. Requires professional installation, DFS, TPC, IPD, and GPS based geolocation. Proposal Update Notes John Notor, Cadence Design Systems, Inc.
Introduction Protection of Incumbents Spectrum Rules Limits on Transmitter Power Etiquette Rules Wrap Up Outline John Notor, Cadence Design Systems, Inc.
On December 20, 2002, the Federal Communications Commission (FCC) released a Notice of Inquiry (NOI)1 regarding "...the feasibility of allowing unlicensed devices to operate in TV broadcast spectrum at locations and times when spectrum is not being used...". The FCC’s NOI on TV band reuse envisions: New opportunities for more commercial utilization of existing spectrum. The right mix of radio technologies to avoid interfering with incumbent users (i.e., TV broadcasters). This presentation proposes, in outline form, regulatory limits for unlicensed use of TV spectrum. This proposal assumes the FCC will be more receptive to a Part 15.247 style set of rules with cognitive radio capabilities to protect incumbents2. Introduction “Notice of Inquiry: Additional Spectrum for Unlicensed Devices Below 900 MHz and in the 3 GHz Band”, ET Docket No. 02-380, December 11, 2002. Ibid, para. 8 John Notor, Cadence Design Systems, Inc.
Incumbents are defined as services which have either primary or secondary status in the TV bands. The FCC identifies the following TV band incumbents3: Full Service Analog and Digital TV Broadcast services licensed under Part 73, which have primary status. Class A TV stations under Part 73 subpart J, which have primary status. Low Power TV, TV translator, and TV booster stations licensed under Part 74, which have secondary status. TV broadcast auxiliary stations on channels 14-69 licensed under Part 74, which have secondary status. Wireless microphones permitted under Part 74 on a non-interfering basis, which have protection from Part 15 devices.. Private Land Mobile Radio Service (PLMRS) operating in the channel 14-20 range under Part 90, which have secondary status. Commercial Mobile Radio Service (CMRS) operating in the channel 14-20 range under Part 20, which have secondary status. Protection of Incumbents Ibid, para. 15 John Notor, Cadence Design Systems, Inc.
Part 15 Devices must have the following cognitive radio capabilities: Dynamic Frequency Selection (DFS) Must select an operating channel which does not interfere with an incumbent, giving highest priority to selecting an unoccupied channel. DFS threshold: A channel is considered unoccupied when the power density received by an omni antenna is less than -110 dBm/100 kHz averaged over 1 ms. The power density limit applies across the entire 6 MHz channel. Must include at least one of the following means to identify and avoid channels occupied by incumbents where signal levels are greater than the DFS threshold. Geolocation: location information combined with a database of incumbent services to identify restricted channels. Incumbent Profile Detection: automatic identification of an incumbent using spectrum signature analysis techniques. Must monitor the channel for a minimum of 60 seconds before commencing operation and continue to monitor the channel between transmissions. Protection of Incumbents – Part 15 Rules John Notor, Cadence Design Systems, Inc.
Part 15 Devices must have the following cognitive radio capabilities (con): Transmit Power Control (TPC) Must be able to reduce operating transmitter power to the minimum required to support reliable communications between any transmitter and any single receiver using appropriate signaling protocols. The transmitter must begin reducing output power when the signal level at the receiver is greater than 20 dB above the receiver’s nominal sensitivity. The TPC function shall keep the signal level at the receiver less than 30 dB above the receiver’s nominal sensitivity at least 50% of the time. Protection of Incumbents – Part 15 Rules John Notor, Cadence Design Systems, Inc.
Part 15 channels restricted to Ch 7-13, 21-36, and 38-51. Operation of Part 15 devices in TV channels is restricted to devices using digital modulations. Frequency hopping devices, or devices using analog modulation techniques are not permitted. Only one transmitter may operate in all or part of a single channel. A device may operate on multiple channels using a single transmitter per channel, provided the data transmitted on one channel is not repeated on any other channel. The transmitter spectrum in any channel must not exceed the limits of the FCC out of band emission mask for a digital TV signal. The aggregate 6 dB bandwidth of the transmitter signal must be 1.5 MHz or greater. The spectral efficiency must be at least 1 bit/Hz. The spectral efficiency is defined as the bit rate divided by the aggregate 6 dB bandwidth of the signal. Transmitters must operate in burst mode, with maximum burst lengths less than 1 second. Spectrum Rules John Notor, Cadence Design Systems, Inc.
Spectrum Rules – DTV Mask John Notor, Cadence Design Systems, Inc.
Low Power Indoor/outdoor operation: 0 dBm maximum. DFS, TPC, IPD required. Antenna gain at full transmitter power is limited to 6 dBi maximum. The maximum permitted peak transmitter power shall be reduced 1 dB for every dB of antenna gain above 6 dBi. Rural Outdoor Only Operation: 6 Watts for outdoor operation in environments < 25% TV broadcast incumbent occupancy, 2 unused guard channels (i.e. no broadcast incumbent) on each side. 25 Watts for outdoor operation with < 10% TV broadcast incumbent occupancy, 2 unused guard channels on each side. Antenna gain shall be decreased by 1 dB for each 3 dB increase in antenna gain above 6 dBi. Sectorized antennas are permitted, with 60 degree minimum sector beamwidth, each sector may operate at maximum permitted power. Requires professional installation, DFS, TPC, IPD, and GPS based geolocation. Transmitter Power John Notor, Cadence Design Systems, Inc.
Must use a ‘listen before talk’ signaling etiquette, with a received data acknowledgement mechanism as part of the operation of the device. A random backoff mechanism prior to retransmission of unacknowledged data must be included in the device. Etiquette Rules John Notor, Cadence Design Systems, Inc.
The rules outlined here represent some preliminary thinking to generate discussion within SG1 and form the initial basis for a future proposal for rulemaking to the FCC. Wrap Up John Notor, Cadence Design Systems, Inc.