A number of wireless electrical signaling schemes including sending electric currents through water and the ground using electrostatic and electromagnetic induction were investigated for telegraphy in the late 19th century before practical radio systems became available. These included a patented induction system by Thomas Edison allowing a telegraph on a running train to connect with telegraph wires running parallel to the tracks, a William Preece induction telegraph system for sending messages across bodies of water, and several operational and proposed telegraphy and voice earth conduction systems.
By the early 1990s, the MOSFET had replaced the BJT as the core component of RF technology, leading to a revolution in wireless technology. Power MOSFET devices, particularly the LDMOS, became the standard RF power amplifier technology, which led to the development and proliferation of digital wireless networks. RF CMOS integrated circuits also enabled sophisticated, low-cost and portable end-user terminals, and gave rise to small, low-cost, low-power and portable units for a wide range of wireless communication systems. This enabled "anytime, anywhere" communication and helped bring about the wireless revolution, leading to the rapid growth of the wireless industry. RF CMOS is used in the radio transceivers of all modern wireless networking devices and mobile phones, and is widely used to transmit and receive wireless signals in a variety of applications, such as satellite technology (e.g. GPS), bluetooth, Wi-Fi, near-field communication (NFC), mobile networks (e.g. 3G and 4G), terrestrial broadcast, and automotive radar applications, among other uses.
The core component of this revolution is the MOSFET (metal-oxide-semiconductor field-effect transistor, or MOS transistor). Power MOSFETs such as LDMOS (lateral-diffused MOS) are used in RF power amplifiers to boost RF signals to a level that enables long-distance wireless network access for consumers, while RF CMOS (radio frequency CMOS) circuits are used in radio transceivers to transmit and receive wireless signals at low cost and with low power consumption. The MOSFET is the basic building block of modern wireless networks, including mobile networks such as 2G, 3G and 4G. Most of the essential elements in modern wireless networks are built from MOSFETs, including the base station modules, routers, RF circuits, radio transceivers, transmitters, and RF power amplifiers. MOSFET scaling is also the primary factor behind rapidly increasing wireless network bandwidth, which has been doubling every 18 months, as noted by Edholm's law.
In recent years, an important contribution to the growth of wireless communication networks has been interference alignment, which was discovered by Syed Ali Jafar at the University of California, Irvine. According to Paul Horn, this has "revolutionized our understanding of the capacity limits of wireless networks" and "demonstrated the astounding result that each user in a wireless network can access half of the spectrum without interference from other users, regardless of how many users are sharing the spectrum."
The wireless revolution began in the 1990s, with the advent of digital wireless networks leading to a social revolution, and a paradigm shift from wired to wireless technology, including the proliferation of commercial wireless technologies such as cell phones, mobile telephony, pagers, wireless computer networks, cellular networks, the wireless Internet, and laptop and handheld computers with wireless connections. The wireless revolution has been driven by advances in radio frequency (RF) and microwave engineering, and the transition from analog to digital RF technology, which enabled a substantial increase in voice traffic along with the delivery of digital data such as text messaging, images and streaming media.
There are several wireless standards and solutions for sensor node connectivity. Thread and ZigBee can connect sensors operating at 2.4 GHz with a data rate of 250kbit/s. Many use a lower frequency to increase radio range (typically 1 km), for example Z-wave operates at 915 MHz and in the EU 868 MHz has been widely used but these have a lower data rate (typically 50 kb/s). The IEEE 802.15.4 working group provides a standard for low power device connectivity and commonly sensors and smart meters use one of these standards for connectivity. With the emergence of Internet of Things, many other proposals have been made to provide sensor connectivity. LORA is a form of LPWAN which provides long range low power wireless connectivity for devices, which has been used in smart meters. Wi-SUN connects devices at home. NarrowBand IOT and LTE-M can connect up to millions of sensors and devices using cellular technology.
Internet service providers (ISP's) are looking for ways to expand gigabit per second (Gbit/s) high-speed services to their customers. These can be achieved through fiber to the premises broadband network architecture, or a more affordable alternative using fixed wireless in the last mile in combination with the fiber networks in the middle mile in order to reduce the costs of trenching fiber optic cables to the users. In the United States, 60 GHz V band is unlicensed. This makes the V band an appealing choice to be used as fixed wireless access for Gbit/s services to connect to homes and businesses. Similarly, 70/80 GHz E band is lightly licensed which can be more accessible to more providers to provide such services.
Wired intercom is inherently private, so long as the wiring system isn't tapped by outside parties. Wireless intercom is not inherently private; conversations on a wireless intercom are broadcast using publicly available wireless frequencies which means other users with similar devices could listen in if they are within range. Most units on the market will allow intercom conversations to be heard through other devices such as scanners, baby monitors, cordless telephones, or the same brand of wireless intercom.
In January 2016, a startup company Starry from Boston introduced Starry Point with the goal to provide Gbit/s speed internet wirelessly to homes. The device is a fixed wireless unit attached to a window as an access point to connect to Starry core networks using a millimetre wave band communication. The company did not reveal the details of the band, but claimed to be "the world’s first millimeter wave band active phased array technology for consumer internet communications". However, in January 2018, at the time that the company announced the expansion of its beta service to cover 3 cities: Boston, Los Angeles, and Washington, DC, the speeds were still limited to up to 200 Mbit/s.
Cricket Communications, Inc. d.b.a. Cricket Wireless or simply Cricket, founded in 1999, was a subsidiary of Leap Wireless International, Inc. prior to Leap's acquisition by AT&T. It provides prepaid wireless services in the United States.
Wireless intercom privacy can be provided if the audio stream is encrypted. Telex, HME, Altair and other intercom manufacturers offer encrypted wireless intercom for corporate, military and sports team customers desiring instant voice communications with privacy. The first use of encrypted wireless intercom in American football was in 1996; by 1999 it was being used in the Super Bowl. Audio frequency response of current products is limited to less than 4 kHz; this means that natural vocal sibilances above 4 kHz are absent. Ess sounds like eff, requiring additional spoken clarification such as saying "'S' as in 'Sam'".
Wireless personal area networks (WPANs) connect devices within a relatively small area, that is generally within a person's reach. For example, both Bluetooth radio and invisible infrared light provides a WPAN for interconnecting a headset to a laptop. ZigBee also supports WPAN applications. Wi-Fi PANs are becoming commonplace (2010) as equipment designers start to integrate Wi-Fi into a variety of consumer electronic devices. Intel "My WiFi" and Windows 7 "virtual Wi-Fi" capabilities have made Wi-Fi PANs simpler and easier to set up and configure.
Products using the IEEE 802.11 WLAN standards are marketed under the Wi-Fi brand name. Fixed wireless technology implements point-to-point links between computers or networks at two distant locations, often using dedicated microwave or modulated laser light beams over line of sight paths. It is often used in cities to connect networks in two or more buildings without installing a wired link. To connect to Wi-Fi, sometimes are used devices like a router or connecting HotSpot using mobile smartphones.
i-wireless dba Access Wireless is a service provider for the government-funded Lifeline Assistance program. The Lifeline Assistance program was designed to ensure that quality telecommunications services are available to low-income customers at reasonable and affordable rates. Customers who qualify for the program receive a free allotment of voice, text and data, and may receive a free mobile phone- dependent on individual state regulations.
Kroger Wireless invites customers to purchase phones at select Kroger store locations, via their website, or by bringing their eligible Sprint device for activation. In addition, it hosts the Kroger Wireless My Account app for Android or iOS mobile customers.
In October 2017, Newark Fiber enabled its first customer in Newark, New Jersey with 10 Gbit/s fixed wireless service. Newark Fiber used V-band 10 Gbit/s transmitters with the distance of up to 1.8 km.
SafeLink Wireless is a Lifeline supported service, operated by TracFone's Net10 Wireless subsidiary. Lifeline is a, government benefit program which subsidizes discounted or free phone service, only offered to eligible low-income or disabled consumers. The service is non-transferrable, and limited to one mobile or landline Lifeline phone line per household. Lifeline is funded through the Universal Service Fund.
Net10 Wireless sells Android phones by LG and Samsung, and some generations of the iPhone, and sells SIM cards that can be used in unlocked AT&T, T-Mobile, Sprint, Verizon, or other GSM phones.
Total Wireless offers a variety of Smartphones which can operate on Verizon's 4G LTE network. Devices and service plans can be purchased via the Total Wireless website, Walmart website, as well as in-store at Walmart, Target and Dollar General. These phones use CDMA for voice, not Verizon's VoLTE; they use LTE only for data exchange.
Wireless metropolitan area networks are a type of wireless network that connects several wireless LANs. * WiMAX is a type of Wireless MAN and is described by the IEEE 802.16 standard.