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Wideband Audio
Wideband audio, also known as wideband voice or HD voice, is high definition voice quality for telephony audio, contrasted with standard digital telephony "toll quality". It extends the frequency, frequency range of audio signals transmitted over telephone lines, resulting in higher quality speech. The range of the human voice extends from 100 Hz to 17 kHz but traditional, voice frequency, voiceband or narrowband telephone calls limit audio frequencies to the range of 300 Hz to 3.4 kHz. Wideband audio relaxes the bandwidth limitation and transmits in the audio frequency range of 50 Hz to 7 kHz. In addition, some wideband codecs may use a higher audio bit depth of 16 bits to encode samples, also resulting in much better voice quality. Wideband codecs have a typical sample rate of 16 kHz. For superwideband codecs the typical value is 32 kHz. History In 1987, the International Telecommunication Union (ITU) standardized a version of wideband a ...
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Voice Frequency
A voice frequency (VF) or voice band is the range of audio frequencies used for the transmission of speech. Frequency band In telephony, the usable voice frequency band ranges from approximately 300 to 3400  Hz. It is for this reason that the ultra low frequency band of the electromagnetic spectrum between 300 and 3000 Hz is also referred to as ''voice frequency'', being the electromagnetic energy that represents acoustic energy at baseband. The bandwidth allocated for a single voice-frequency transmission channel is usually 4 kHz, including guard bands, allowing a sampling rate of 8 kHz to be used as the basis of the pulse-code modulation system used for the digital PSTN. Per the Nyquist–Shannon sampling theorem, the sampling frequency (8 kHz) must be at least twice the highest component of the voice frequency via appropriate filtering prior to sampling at discrete times (4 kHz) for effective reconstruction of the voice signal. Fundamental ...
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Videoconferencing
Videotelephony (also known as videoconferencing or video calling) is the use of audio signal, audio and video for simultaneous two-way communication. Today, videotelephony is widespread. There are many terms to refer to videotelephony. ''Videophones'' are standalone devices for video calling (compare Telephone). In the present day, devices like smartphones and computers are capable of video calling, reducing the demand for separate videophones. ''Videoconferencing'' implies group communication.Mulbach et al, 1995. pg. 291. Videoconferencing is used in telepresence, whose goal is to create the illusion that remote participants are in the same room. The concept of videotelephony was conceived in the late 19th century, and versions were available to the public starting in the 1930s. Early demonstrations were installed at booths in post offices and shown at various world expositions. In 1970, AT&T launched the first commercial personal videotelephone system. In addition to videoph ...
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Grandstream Networks
Grandstream Networks is a manufacturer of IP voice and video communications equipment, video surveillance, gateways and analog telephone adapters (ATAs), and Asterisk-based IP-PBX appliances. Grandstream supplies small and medium businesses and consumers with open-standard SIP-based products. Grandstream Networks is headquartered in Boston, Massachusetts, and has offices in Plano, Texas, Los Angeles, California in the US, in Casablanca in Morocco, Valencia, Venezuela, and in Shenzhen Shenzhen is a prefecture-level city in the province of Guangdong, China. A Special economic zones of China, special economic zone, it is located on the east bank of the Pearl River (China), Pearl River estuary on the central coast of Guangdong ..., China. The company was founded by David Li in 2002 and is headquartered in Boston, Massachusetts. References {{Reflist Telecommunications equipment vendors Videotelephony VoIP companies of the United States Technology companies based in the ...
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NEC Unified Solutions
is a Japanese multinational information technology and electronics corporation, headquartered at the NEC Supertower in Minato, Tokyo, Japan. It provides IT and network solutions, including cloud computing, artificial intelligence (AI), Internet of Things (IoT) platform, and telecommunications equipment and software to business enterprises, communications services providers and to government agencies. NEC has also been the largest PC vendor in Japan since the 1980s when it launched the PC-8000 series; it currently operates its domestic PC business in a joint venture with Lenovo. NEC was the world's fourth-largest PC manufacturer by 1990. Its semiconductors business unit was the world's largest semiconductor company by annual revenue from 1985 to 1992, the second largest in 1995, one of the top three in 2000, and one of the top 10 in 2006. NEC spun off its semiconductor business to Renesas Electronics and Elpida Memory. Once Japan's major electronics company, NEC has largely ...
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Cisco Systems
Cisco Systems, Inc. (using the trademark Cisco) is an American multinational corporation, multinational digital communications technology conglomerate (company), conglomerate corporation headquartered in San Jose, California. Cisco develops, manufactures, and sells networking hardware, software, telecommunications equipment and other high-technology services and products. Cisco specializes in specific tech markets, such as the Internet of things (IoT), internet domain, domain security, videoconferencing, and energy management with List of Cisco products, products including Webex, OpenDNS, XMPP, Jabber, Duo Security, Silicon One, and Cisco Jasper, Jasper. Cisco Systems was founded in December 1984 by Leonard Bosack and Sandy Lerner, two Stanford University computer scientists who had been instrumental in connecting computers at Stanford. They pioneered the concept of a local area network (LAN) being used to connect distant computers over a multiprotocol router (computing), route ...
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Avaya
Avaya LLC(), formerly Avaya Inc., is an American multinational technology company headquartered in Morristown, New Jersey, that provides cloud communications and workstream collaboration services. The company's platform includes unified communications and contact center services. In 2019, the company provided services to 220,000 customer locations in 190 countries. History In 1995, AT&T Corporation renamed their subsidiary AT&T Technologies to Lucent Technologies and spun it off in 1996. Lucent subsequently spun off units of its own in an attempt to restructure its struggling operations. Avaya Inc. was spun off from Lucent as its own company in 2000 (Lucent merged with Alcatel SA in 2006, becoming Alcatel-Lucent, which was purchased in turn by Nokia Nokia Corporation is a Finnish multinational corporation, multinational telecommunications industry, telecommunications, technology company, information technology, and consumer electronics corporation, originally establish ...
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Sony
is a Japanese multinational conglomerate (company), conglomerate headquartered at Sony City in Minato, Tokyo, Japan. The Sony Group encompasses various businesses, including Sony Corporation (electronics), Sony Semiconductor Solutions (imaging and sensing), Sony Entertainment (including Sony Pictures and Sony Music Group), Sony Interactive Entertainment (video games), Sony Financial Group, and others. Sony was founded in 1946 as by Masaru Ibuka and Akio Morita. In 1958, the company adopted the name Initially an electronics firm, it gained early recognition for products such as the TR-55 transistor radio and the CV-2000 home video tape recorder, contributing significantly to Japan's Japanese economic miracle, post-war economic recovery. After Ibuka's retirement in the 1970s, Morita served as chairman until 1994, overseeing Sony's rise as a global brand recognized for innovation in consumer electronics. Landmark products included the Trinitron color television, the Walkma ...
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Samsung
Samsung Group (; stylised as SΛMSUNG) is a South Korean Multinational corporation, multinational manufacturing Conglomerate (company), conglomerate headquartered in the Samsung Town office complex in Seoul. The group consists of numerous affiliated businesses, most of which operate under the Samsung brand, and is the largest (business conglomerate) in South Korea. Samsung has the world's List of most valuable brands, fifth-highest brand value. Founded in 1938 by Lee Byung-chul as a trading company, Samsung diversified into various sectors, including food processing, textiles, insurance, securities, and retail, over the next three decades. In the late 1960s, Samsung entered the electronics industry, followed by the construction and shipbuilding sectors in the mid-1970s—areas that would fuel its future growth. After Lee died in 1987, Samsung was divided into five business groups: Samsung Group, Shinsegae Group, CJ Group, Hansol Group, and JoongAng Ilbo, JoongAng Group. K ...
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Nokia
Nokia Corporation is a Finnish multinational corporation, multinational telecommunications industry, telecommunications, technology company, information technology, and consumer electronics corporation, originally established as a pulp mill in 1865. Nokia's main headquarters are in Espoo, Finland, in the Helsinki metropolitan area, but the company's actual roots are in the Tampere region of Pirkanmaa.HS: Nokian juuret ovat Tammerkosken rannalla
(in Finnish)
In 2020, Nokia employed approximately 92,000 people across over 100 countries, did business in more than 130 countries, and reported annual revenues of around €23 billion. Nokia is a public limited company listed on the Nasdaq Helsinki and New York Stock Exchange. It was the world's 415th-largest company ...
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Google
Google LLC (, ) is an American multinational corporation and technology company focusing on online advertising, search engine technology, cloud computing, computer software, quantum computing, e-commerce, consumer electronics, and artificial intelligence (AI). It has been referred to as "the most powerful company in the world" by the BBC and is one of the world's List of most valuable brands, most valuable brands. Google's parent company, Alphabet Inc., is one of the five Big Tech companies alongside Amazon (company), Amazon, Apple Inc., Apple, Meta Platforms, Meta, and Microsoft. Google was founded on September 4, 1998, by American computer scientists Larry Page and Sergey Brin. Together, they own about 14% of its publicly listed shares and control 56% of its stockholder voting power through super-voting stock. The company went public company, public via an initial public offering (IPO) in 2004. In 2015, Google was reorganized as a wholly owned subsidiary of Alphabet Inc. Go ...
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Apple Inc
Apple Inc. is an American multinational corporation and technology company headquartered in Cupertino, California, in Silicon Valley. It is best known for its consumer electronics, software, and services. Founded in 1976 as Apple Computer Company by Steve Jobs, Steve Wozniak and Ronald Wayne, the company was incorporated by Jobs and Wozniak as Apple Computer, Inc. the following year. It was renamed Apple Inc. in 2007 as the company had expanded its focus from computers to consumer electronics. Apple is the largest technology company by revenue, with  billion in the 2024 fiscal year. The company was founded to produce and market Wozniak's Apple I personal computer. Its second computer, the Apple II, became a best seller as one of the first mass-produced microcomputers. Apple introduced the Lisa in 1983 and the Macintosh in 1984, as some of the first computers to use a graphical user interface and a mouse. By 1985, internal company problems led to Jobs leavin ...
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3GPP
The 3rd Generation Partnership Project (3GPP) is an umbrella term for a number of standards organizations which develop protocols for mobile telecommunications. Its best known work is the development and maintenance of: * GSM and related 2G and 2.5G standards, including GPRS and EDGE * UMTS and related 3G standards, including HSPA and HSPA+ * LTE and related 4G standards, including LTE Advanced and LTE Advanced Pro * 5G NR and related 5G standards, including 5G-Advanced * An evolved IP Multimedia Subsystem (IMS) developed in an access independent manner 3GPP is a consortium with seven national or regional telecommunication standards organizations as primary members ("organizational partners") and a variety of other organizations as associate members ("market representation partners"). The 3GPP organizes its work into three different streams: Radio Access Networks, Services and Systems Aspects, and Core Network and Terminals. The project was established in Decembe ...
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