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Federal Internet Law & Policy
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Wireless :: Unlicensed :: Part 15 :: WiFi Dont be a FOOL; The Law is Not DIY

Part 15 is Unlicensed but Authorized. An individual does not need a license to operate in this spectrum, but the equipment must be authorized and operate pursuant to regulations. Three types of unlicensed Service are defined and regulated under the Part 15 rules:

Networking devices which utilize Part 15 spectrum are intentional radiators.

"Spread spectrum is a term applied to communications systems that spread radio frequency energy over a wide bandwidth by means of an auxiliary spreading code. The spreading of the bandwidth can be accomplished in many different ways and the systems are usually classified by the type of spreading technique which they employ. They are commonly referred to as: direct sequence (or pseudonoise), frequency hopping, time hopping, pulsed FM (or chirp) and hybrid systems. The spreading or dilution of the energy in spread spectrum systems over a wide bandwidth results in several possible advantages: short range interference-free overlays on other emissions, resistance to interference from other emissions, and low detectability. While we do not anticipate that spread spectrum will replace other types of modulations, the unique characteristics of spread spectrum offer important options for the communications system designer." 1984 NPRM

Authorization

Equipment and systems must be authorized by the FCC or telecommunications certification body. There should be a label on the equipment indicating certification. "These devices may not be imported and/or marketed until they have shown compliance with the technical standards which have been specified by the Commission. " FCC Authorization Page.

Derived From: Kenneth Carter, Ahmed Lahjouji, Neal McNeal, Unlicensed and Unshackled: A Joint OSP-OET White Paper on Unlicensed Devices and Their Regulatory IssuesPDF, OSP Working Paper 39 (May 2004):

Types of Part 15 Intentional Radiators

Commons Property Regime

Part 15 spectrum is "unlicensed." Anyone can transmit and operate in this spectrum with appropriate certified devices as long as they comply with the conditions of operations. "Persons operating intentional or unintentional radiators shall not be deemed to have any vested or recognizable right to continued use of any given frequency..." They cannot cause harmful interference to others and they must accept interference. Operators in Part 15 spectrum obtain no superior rights; while anyone may use the spectrum, no one may exclude others from using the spectrum.

In terms of property rights, this spectrum is a "commons." All have access to the resource - no one can exclude others from the resource - and the use of the resource is potentially rivalrous (the use of the resource by one detracts from the use of the resource by others, leading to a potential "tragedy of the commons"). [Faulhaber p 204 ("Part 15 spectrum has property rights akin to that of a commons: an asset available for the use of all, with common restrictions governing use restrictions for all" p 208 "'building fences' of property rights violates the commons principle.")] [Sicker p 3 ("Unlicensed wireless commons seems to fit more closely the model of a common resource pool, since additional users cannot be precluded from turning on their radios, but as users are added, the ability to communicate diminishes with increasing mutual interference.")] [Benkler 1998 p 7 ("This UNII Band, as it is called, creates a legal space for the first broadband infrastructure commons.")]

The FCC itself did not refer to this spectrum as a "commons." Its justification for the creation of the UNII bands as unlicensed rested primarily on the fact that these would be very short ranged services and "like other existing unlicensed devices, we believe that trying to license UNII devices individually would be administratively difficult if not impossible for both the Commission and the consumer and would greatly delay the implementation and use of this band by UNII devices." Therefore UNII is "more amenable to an unlicensed structure." UNII Order 1997 para 87.

License regimes had been put into place for the purpose of avoiding interference. [Faulhaber] Now the policy objective of avoiding interference would be achieved through (a) low powered short range transmitters and (b) the creation of a radio etiquette such that radios would technologically avoid interference.

The reality of the "tragedy of the commons" in Part 15 spectrum has been questionable. [Sicker] The classic tragedy of the commons is a common grassland where cattle graze. As all farmers have an incentive to utilize this resource to the fullest possible extent, and no farmers have an incentive to either conserve or replenish the grass in the grassland, the common land will be over grazed, the grass will be depleted, and no grass will be left for others. The distinction, however, between grassland and Part 15 spectrum is that with grassland, if the grass is depleted in one moment, it takes several months to grow back. With spectrum, if the bandwidth unavailable in one moment, it can be fully available in the next, fully "replenished."

How Common Goods relate to other types of property:

  Excludable Non Excludable
Rivalrous Private Goods
ex: food, clothing, toys, furniture, cars
Common Goods
ex: water, fish, hunting game, Part 15 spectrum
Non Rivalrous Club Goods
Ex: Cable Television
Public Goods
Ex: National Defense, free-to-air TV

Standards

Derived From: Connected & on the Go; Broadband Goes Wireless, Report of the FCC Wireless Broadband Access Task Force, p. 14, Feb. 2005

"The Commission’s Part 15 rules provide manufacturers with the flexibility to manufacture unlicensed devices using any technology as long as the devices comply with certain technical parameters that vary according to the particular bands of operation. In practice, unlicensed devices operate pursuant to both proprietary standards and industry-established standards. Many manufacturers manufacture proprietary equipment, which does not comport with any particular voluntary standard. Differentiating particular product features or functionality and tailoring equipment to particular applications are two reasons some manufacturers opt not to manufacture according to industry standards. Alternatively, many manufacturers develop equipment that operates pursuant to voluntary standards established by industry standards groups. These latter standards ensure interoperability between equipment manufactured by a variety of vendors. Some typical industry-developed standards used for unlicensed devices include Wi-Fi (IEEE 802.11), Bluetooth, and WiMax (IEEE 802.16).

Derived From: FTC Report: Should Municipalities Provide Wireless Internet Service? p. 8-9 Oct 2006

“Wireless fidelity” (“Wi-Fi”) is the most commonly used wireless Internet standard today. Wi-Fi is a registered trademark term promoted by the Wi-Fi Alliance, a group of wireless Internet hardware and software providers that certify “802.11” products for network interoperability. An 802.11 network refers to a family of specifications approved by the Institute of Electrical and Electronics Engineers (“IEEE”) in 1997 for a wireless, over-the-air interface Local Area Network (“WLAN”). Generally, computer users can access the Internet with a high speed wireless connection if they are within 300 feet of a transmitting antenna and have the appropriate receiving hardware installed in their computer. Wi-Fi provides data transmission at speeds of up to 11-54 Mbps. Wi-Fi is commonly used to provide wireless Internet “hot spot” connections in coffee shops, airports, and on university campuses. The number of Wi-Fi hot spots in the U.S. has grown exponentially in recent years and may now number as many as 150,000, with approximately 30 million users.

Standard
Frequency
Band
Modulation
Data Rate
802.11(b)
2.4 GHz
DDS
11 MB/s
802.11(g)
2.4 GHz
OFDM
54 MB/s
802.11(a)
5.8 GHz
OFDM
54 MB/s

"Wi-Fi networks can be set up by installing multiple toaster-size antennas on street lights, traffic signals, and buildings, so that multiple wireless hotspots overlap each other to form a continuous “mesh” network of wireless signals. In order to provide an initial connection to the Internet and to manage network traffic, “backbone” technology (also called “backhaul” technology) must be installed at one or more points connected to the network. The installation of such a wireless network may be less expensive than installing a wireline network of the same size. ... (See Municipal Broadband)

"A user must have a computer or other device that is configured for wireless Internet use. Newer laptop computers often have such wireless connectivity built-in to them at the factory. Older computers may be adapted through the addition of a wireless Internet “card.” "

Broadband Plan Recommendations

Regulations

Part 15 dates back to 1938, originally created to cover "wireless phonographs." [Faulhaber p 204] While users of Part 15 spectrum do not need licenses, Part 15 devices must first be certified by the FCC. Part 15 devices also generally operate at low power limits.

 

Frequency Select Regulations Examples
125 kHz   RFID
13.56 MHz   RFID
800-1000 MHz   RFID
902-928 MHz 47 CFR § 15.245-248 ISM Band Allows 1 Watt Transmitter Power

Cordless Phones, Walkie Talkies, Baby Monitors, Garage Door Openers

Microwave oven 750 w

2400 - 2483 MHz ISM Band Allows 1 Watt Transmitter Power  

2435-2465 MHz

Industrial Scientific and Medical Band (ISM)

47 CFR § 15.245-248

Wireless Networking: 802.11b : 22 MHz (2.4 GHz Band) : 11 Mbps Channel Capacity : 5.5 Mbps Typical Data Rate : Range 250' [Working Paper 39 p 29]

Wireless Networking: 802.11g : 40 MHz (2.4 GHz Band) : 54 Mbps Channel Capacity : 32 Mbps Typical Data Rate : Range 150' [Working Paper 39 p 29]

Wireless Networking: Bluetooth : 1 MHz (2.4 GHz Band) : 1 Mbps Channel Capacity : 721 Kbps Typical Data Rate : Range 30' [Working Paper 39 p 29] 2450 MHz

Wireless Networking: HomeRF : 1-5 MHz (2.4 GHz Band) : 10 Mbps Channel Capacity : Range 150' [Working Paper 39 p 29]

Cisco, Enterprise Best Practices for iOS Devices on Cisco Wireless LAN, at 4 (rev. Nov. 2016) (due to congestion, Google and Apple have concluded that 2.4 MHz “is not considered as best suiting the needs for business . . . applications.”)

Cordless Phones, Walkie Talkies, Baby Monitors, Garage Door Openers. Wireless T1 replacements / Ethernet Bridges, RFID WiFi

Microwave oven 900 w

3650 - 3700 MHz Licensed, Non Exclusive. Power limit 1 watt? FCC Order June 2007  
5.091 - 5.25 GHz "WRC-95 allocated this band on a primary basis to fixed-satellite (Earth-to-space) service (FSS uplinks) to provide feeder links for non geostationary satellite systems in the mobile satellite service (MSS) on a coprimary basis with government aeronautical radionavigation." UNII Order 1997 para 6 (why the 5.15 - 5.25 GHz UNII band is indoor only)  

5.15-5.25 GHz UNII

Indoor
[47 CFR § 15.407 (e)]

the maximum conducted output power over the frequency band of operation shall not exceed the lesser of 50 mW or 4 dBm + 10 log B, where B is the 26-dB emission bandwidth in MHz. In addition, the peak power spectral density shall not exceed 4 dBm in any 1-MHz band. If transmitting antennas of directional gain greater than 6 dBi are used, both the maximum conducted output power and the peak power spectral density shall be reduced by the amount in dB that the directional gain of the antenna exceeds 6 dBi. [47 CFR § 15.407 (a)(1)] all emissions outside of the 5.15-5.35 GHz band shall not exceed an EIRP of -27 dBm/MHz. [47 CFR § 15.407 (b)(1)] Wireless LANs, WiFi
5.25-5.35 GHz UNII the maximum conducted output power over the frequency bands of operation shall not exceed the lesser of 250 mW or 11 dBm + 10 log B, where B is the 26 dB emission bandwidth in megahertz. In addition, the peak power spectral density shall not exceed 11 dBm in any 1 megahertz band. If transmitting antennas of directional gain greater than 6 dBi are used, both the maximum conducted output power and the peak power spectral density shall be reduced by the amount in dB that the directional gain of the antenna exceeds 6 dBi. [47 CFR § 15.407 (a)(2)] all emissions outside of the 5.15-5.35 GHz band shall not exceed an EIRP of -27 dBm/MHz. Devices operating in the 5.25-5.35 GHz band that generate emissions in the 5.15-5.25 GHz band must meet all applicable technical requirements for operation in the 5.15-5.25 GHz band (including indoor use) or alternatively meet an out-of-band emission EIRP limit of -27 dBm/MHz in the 5.15-5.25 GHz band. [47 CFR § 15.407 (b)(2)] Wireless LANs, WiFi
5.47-5.725 GHz UNII the maximum conducted output power over the frequency bands of operation shall not exceed the lesser of 250 mW or 11 dBm + 10 log B, where B is the 26 dB emission bandwidth in megahertz. In addition, the peak power spectral density shall not exceed 11 dBm in any 1 megahertz band. If transmitting antennas of directional gain greater than 6 dBi are used, both the maximum conducted output power and the peak power spectral density shall be reduced by the amount in dB that the directional gain of the antenna exceeds 6 dBi. [47 CFR § 15.407(a)(2)] all emissions outside of the 5.47-5.725 GHz band shall not exceed an EIRP of -27 dBm/MHz. [47 CFR § 15.407 (b)(3)] Wireless LANs, WiFi
5725 - 5875 MHz ISM Band Allows 1 Watt Transmitter Power. Link Nodes Campus.  
5785-5815 MHz 47 CFR § 15.245-248 Wireless T1 replacements / Ethernet Bridges, RFID
5.725-5.825 GHz UNII

the maximum conducted output power over the frequency band of operation shall not exceed the lesser of 1 W or 17 dBm + 10 log B, where B is the 26-dB emission bandwidth in MHz. In addition, the peak power spectral density shall not exceed 17 dBm in any 1-MHz band. If transmitting antennas of directional gain greater than 6 dBi are used, both the maximum conducted output power and the peak power spectral density shall be reduced by the amount in dB that the directional gain of the antenna exceeds 6 dBi. However, fixed point-to-point U-NII devices operating in this band may employ transmitting antennas with directional gain up to 23 dBi without any corresponding reduction in the transmitter peak output power or peak power spectral density. For fixed, point-to-point U-NII transmitters that employ a directional antenna gain greater than 23 dBi, a 1 dB reduction in peak transmitter power and peak power spectral density for each 1 dB of antenna gain in excess of 23 dBi would be required. Fixed, point-to-point operations exclude the use of point-to-multipoint systems, omnidirectional applications, and multiple collocated transmitters transmitting the same information. The operator of the U-NII device, or if the equipment is professionally installed, the installer, is responsible for ensuring that systems employing high gain directional antennas are used exclusively for fixed, point-to-point operations. 47 CFR § 15.407(a)(2)all emissions within the frequency range from the band edge to 10 MHz above or below the band edge shall not exceed an EIRP of -17 dBm/MHz; for frequencies 10 MHz or greater above or below the band edge, emissions shall not exceed an EIRP of -27 dBm/MHz. [47 CFR § 15.407 (b)(4)]

Wireless Networking: 802.11a : 40 MHz (5.7 GHz Band) : 54 Mbps Channel Capacity : 32 Mbps Typical Data Rate : Range 75' [Working Paper 39 p 29]

Wireless LANs, WiFi
5.9 Ghz The Comm’n Seeks to Update and Refresh the Record in the “Unlicensed Nat’l Info. Infrastructure (U-NII) Devices in the 5 GHz Band” Proceeding, Public Notice, 31 FCC Rcd. 6130, 6133 (2016).  
10500-10550 MHz 47 CFR § 15.245-248  
24075-24175 MHz 47 CFR § 15.245-248  
57-64 GHz   "used for transferring large volumes of data over relatively short distances"
64 - 71 GHz Use of Spectrum Bands Above 24 GHz for Mobile Radio Services, et al., Report and Order and Further Notice of Proposed Rulemaking, 31 FCC Rcd. 8014, 8062 ¶ 125 (2016).  

VoIP

3650 - 3700 MHz

Derived From: FCC Wireless Services 3650-3700 MHz Radio Service: "On March 10, 2005, the Commission adopted a Report and Order, FCC 05-56 ( pdf ), establishing service rules to open the 3650 MHz band for terrestrial fixed and mobile wireless broadband operations. In the Memorandum Opinion and Order, FCC 07-99 ( pdf ), adopted on May 22, 2007, the Commission addressed petitions for reconsideration of the Report and Order by affirming the rules and policies adopted in 2005 while at the same time ensuring that incumbent, grandfathered Earth stations and Federal radiolocation stations in this band are protected from harmful interference. The Commission adopted a flexible and innovative regulatory framework for the 3650-3700 MHz band that would not require traditional frequency coordination among non-Federal users with the exception of incumbent Fixed Satellite Service Licensees (FSS). These rules involve minimal regulatory burdens to encourage multiple entrants and to stimulate the rapid expansion of broadband services, especially in America's rural heartland. A license for the 3650-3700 MHz Radio Service will consist of a non-exclusive nationwide license , combined with fixed and base station registration . All interested parties must have a non-exclusive nationwide license prior to registering a fixed or base station. Mobile and portable stations, which are typically used by consumers, i.e. , end users or subscribers, do not require a separate license and do not have to be registered in ULS. The non-exclusive nationwide license does not authorize operation until each base or fixed station is registered and in an "Accepted" status and the nationwide license is updated on ULS. The registration process will also facilitate protection of grandfathered, incumbent stations from interference. There are two types of grandfathered, incumbent stations that new 3650 MHz band licensees must protect: non-Federal and Federal.

  • (ET Docket No 04-151; WT Docket No 05-96). See FCC IB >> 3650 MHz Grandfathered Earth Stations. Report and Order (March 10, 2005)
  • FCC opens access to 3650-3700 MHz band, Muni 3/15/2005
  • FCC Opens Access to New Spectrum for Wireless Broadband in the 3650 MHz Band. Press Release, FCC 3/11/2005
  • FCC Adopts Rule Changes for Smart Radios. Press Release, FCC 3/11/2005
  • FCC Protects Spectrum From Software Radio, eWeek 3/11/2005
  • FCC Begins Rulemaking Proposing to Allow Wireless Broadband Operations in the 3650-3700 MHz Band., FCC 4/27/2004
  • FCC PROPOSES RULES TO FACILITATE WIRELESS BROADBAND SERVICES USING VACANT TV CHANNELS. The FCC proposed to allow unlicensed devices to operate in the broadcast television spectrum at locations where the spectrum is not in use by television stations. News Release. (Dkt No 02-380 , 04-186). Adopted: 05/13/2004. News Media Contact: Bruce Romano at 2470 OET. , FCC 5/18/2004

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