Category: Industrial News

Categories: Industrial News

4G Frequency Bands

LTE has been developed to operate on paired spectrum for Frequency Division Duplex (FDD), and unpaired spectrum for Time Division Duplex (TDD).

For an LTE radio system to facilitate bidirectional communication, it is necessary to implement a duplex scheme so that a device may transmit and receive without collision. In order to achieve high data rates, LTE operates full duplex whereby both downlink (DL) and uplink (UL) communication takes place simultaneously by separating DL and UL traffic either by frequency (i.e., FDD), or time periods (i.e., TDD).

While less efficient and more electrically complex to deploy, FDD tends to be more commonly deployed by operators due to refarming of existing 3G spectrum arrangements. By comparison, deploying TDD requires less spectrum as well as eliminating then need for guard bands permitting a more efficient stacking of spectrum. UL/DL capacity can also be dynamically adjusted to match demand simply by devoting more airtime to one over the other. However, transmission timing must be synchronised between base stations, introducing complexity, along with guard periods being required between DL and UL subframes, which reduces capacity.

As the professional 4G landline phone manufacturer, Shenzhen East Line Communication Tech Co., Ltd. can supply and customize different kinds of 4G fixed wireless phones, 4G IP phones, 4G outdoor campus telephones etc. For more information, please visit our website:

https://www.oemtelephone.com/product-category/fixed-wireless-phone/4g-fixed-phone/

FDD LTE Frequency Bands

The continuing evolution of carrier aggregation has resulted in several new bands added, including B29, B32, B67, and B69 used for downlink-only carrier aggregation, termed Supplemental DL bands[5]. Supplemental DL bands 252 and 255 have been included as part of the LTE-U expansion into unlicensed 5 GHz bands U-NII-1 and U-NII-3, respectively.

Release 16.0 in April 2019 saw the introduction of European 450 MHz LTE bands for the purposes of emergency services use during disaster relief.

The below table lists the 39 Frequency Division Duplex and Supplemental Downlink LTE bands, compiled from 3GPP 36.101 (Rel. 17.1) [June 2023]

E-UTRA Band Identifier Uplink (MHz) Downlink (MHz) UL EARFCN DL EARFCN Channel Bandwidths (MHz)
B1 (2100 MHz) IMT Core Band 18000 – 18599 0 – 599 0.2, 5, 10, 15, 20
B2 (1900 MHz) PCS 1900 18600 – 19199 600 – 1199 0.2, 1.4, 3, 5, 10, 15, 20
B3 (1800 MHz) 1800 19200 – 19949 1200 – 1949 0.2, 1.4, 3, 5, 10, 15, 20
B4 (1700 MHz) AWS 1700 19950 – 20399 1950 – 2399 0.2, 1.4, 3, 5, 10, 15, 20
B5 (850 MHz) 850 20400 – 20649 2400 – 2649 0.2, 1.4, 3, 5, 10
B7 (2600 MHz) IMT Extension 20750 – 21449 2750 – 3449 0.2, 5, 10, 15, 20
B8 (900 MHz) 900 21450 – 21799 3450 – 3799 0.2, 1.4, 3, 5, 10
B9 (1800 MHz) 1700 (Japan #2) 21800 – 22149 3800 – 4149 5, 10, 15, 20
B10 (1700 MHz) 3G Americas Extended AWS blocks A-I 22150 – 22749 4150 – 4749 5, 10, 15, 20
B11 (1500 MHz) 1500 (Japan #3) 22750 – 22949 4750 – 4949 5, 10
B12 (700 MHz) US 700 Lower A, B, C 23010 – 23179 5010 – 5179 0.2, 1.4, 3, 5
B13 (700 MHz) US 700 Upper C 23180 – 23279 5180 – 5279 0.2, 5, 10
B14 (700 MHz) US 700 Upper D 23280 – 23379 5280 – 5379 5, 10
B17 (700 MHz) US 700 Lower B, C 23730 – 23849 5730 – 5849 5, 10
B18 (850 MHz) 850 (Japan #4) 23850 – 23999 5850 – 5999 0.2, 5, 10, 15
B19 (850 MHz) 850 (Japan #5) 24000 – 24149 6000 – 6149 0.2, 5, 10, 15
B20 (800 MHz) CEPT 800 24150 – 24449 6150 – 6449 0.2, 5, 10, 15, 20
B21 (1500 MHz) 1500 (Japan #6) 24450 – 24599 6450 – 6599 0.2, 5, 10, 15
B22 (3500 MHz) FDD 3500 24600 – 25399 6600 – 7399 5, 10, 15, 20
B24 (1600 MHz) US L-Band 25700 – 26039 7700 – 8039 5, 10
B25 (1900 MHz) PCS 1900 G 26040 – 26689 8040 – 8689 0.2, 1.4, 3, 5, 10, 15, 20
B26 (850 MHz) E850 Upper 26690 – 27039 8690 – 9039 0.2, 1.4, 3, 5, 10, 15
B27 (850 MHz) E850 Lower LTE 27040 – 27209 9040 – 9209 1.4, 3, 5
B28 (700 MHz) APT 700 27210 – 27659 9210 – 9659 0.2, 1.4, 3, 5, 10, 15, 20
B30 (2300 MHz) LTE WCS 27660 – 27710 9770 – 9869 5, 10
B31 (450 MHz) LTE 450 Brazil 27760 – 27785 9870 – 9919 0.2, 1.4, 3, 5
B65 (2100 MHz) 2 GHz LTE 131072 – 131971 65536 – 66435 1.4, 3, 5, 10, 15, 20
B66 (1700 MHz) AWS Extension 131972 – 132671 66436 – 67335 1.4, 3, 5, 10, 15, 20
B68 (700 MHz) LTE 700 Arab Region 132672 – 132971 67536 – 67835 5, 10, 15
B70 (1700 MHz) AWS-3/4 132972 – 133121 68336 – 68585 5, 10, 15, 20
B71 (600 MHz) US 600 133122 – 133471 68586 – 68935 0.2, 5, 10, 15, 20
B72 (450 MHz) 450 EU BB-PPDR 133472 – 133521 68936 – 68985 0.2, 1.4, 3, 5
B73 (450 MHz) 450 LTE APAC 133522 – 133571 68986 – 69035 0.2, 1.4, 3, 5
B74 (1500 MHz) FDD L-band 133572 – 134001 69036 – 69465 0.2, 1.4, 3, 5, 10, 15, 20
B85 (700 MHz) 700 a+ 134002 – 134181 70366 – 70545 5, 10
B87 (450 MHz) PPDR PMR/PMAR in EU 134182 – 134231 70546 – 70595 0.2, 1.4, 3, 5
B88 (450 MHz) PPDR PMR/PMAR in EU 134231 – 134280 70596 – 70645 0.2, 1.4, 3, 5
B103 (700 MHz) NB-IoT 700 134282 – 134291 70646 – 70655 0.2
B106 (900 MHz) 900 FDD 134292 – 134341 70656 – 70705 1.4, 3

TDD LTE Frequency Bands

The increasing asymmetric demand for downlink data has also resulted in the introduction of Band 46, a downlink-only Supplemental DL band operating in the 5 GHz U-NII frequency range.

Band 47 has been introduced for applications such as Vehicle to Everything (V2X) communications, which is positioned in the U-NII-3 5 GHz unlicensed band. Cellular V2X (C-V2X) may require the use of unlicensed bands to solve regulatory issues related to LTE-Direct, where devices broadcast directly to nearby devices[6]. Like all unlicensed band LTE technologies, V2X operates Band 47 only in carrier aggregation with the operator’s licensed band.

The below table lists the 20 Time Division Duplex and Supplemental Downlink LTE bands, compiled from 3GPP 36.101 (Rel. 17.1) [June 2023]

E-UTRA Band Identifier Frequency (MHz) EARFCN Channel Bandwidths (MHz)
B33 (2100 MHz) TDD 2000 Lower 36000 – 36199 5, 10, 15, 20
B34 (2100 MHz) TDD 2000 Upper 36200 – 36349 5, 10, 15
B35 (1900 MHz) 1900 36350 – 36949 0.2, 1.4, 3, 5, 10, 15, 20
B36 (1900 MHz) TDD 1900 36950 – 37549 0.2, 1.4, 3, 5, 10, 15, 20
B37 (1900 MHz) PCS Center Gap 37550 – 37749 5, 10, 15, 20
B38 (2600 MHz) IMT Extension Gap 37750 – 38249 5, 10, 15, 20
B39 (1900 MHz) China TDD 1900 38250 – 38649 5, 10, 15, 20
B40 (2300 MHz) TDD 2300 38650 – 39649 5, 10, 15, 20
B41 (2500 MHz) TDD 2500 39650 – 41589 5, 10, 15, 20
B42 (3500 MHz) TDD 3500 41590 – 43589 5, 10, 15, 20
B43 (3700 MHz) TDD 3700 43590 – 45589 5, 10, 15, 20
B44 (700 MHz) APT 700 TDD 45590 – 46589 3, 5, 10, 15, 20
B45 (1500 MHz) China TDD 1400 46590 – 46789 5, 10, 15, 20
B46 (5200 MHz) LAA 5200 46790 – 54539 10, 20
B47 (5800 MHz) V2X 5800 54540 – 55239 10, 20
B48 (3600 MHz) US CBRS 3500 55240 – 56739 5, 10, 15, 20
B50 (1500 MHz) TD 1500+ 58240 – 59089 3, 5, 10, 15, 20
B51 (1500 MHz) TD 1500- 59090 – 59139 5
B53 (2400 MHz) TDD LTE over WiFi 60140 – 60254 1.4, 3, 5, 10
B54 (1600 MHz) TD 1700 60255 – 60304 5

Shenzhen East Line Communication Tech Co., Ltd.
The professional fixed landline telephones manufacturer

Categories: Industrial News

Fixed Landline Telephone History

4. Foreign investors build Shanghai landline telephone

In 1882, the Great Northern Telegraph Company set up a magnet-type manual telephone exchange at No. 7 on the Bund, erected telegraph poles in the Shanghai Public Concession and the French Concession, and installed 25 telephones. The annual rental fee for telephones per household was 150 yuan. There is a public telephone. This was Shanghai’s first commercial telephone exchange six years after the invention of the telephone, and only five years later than the world’s first telephone company, the American Bell Telephone Company, which is now the American Telephone and Telegraph Company (AT&T).

At that time, there were 41 actual users, including 38 foreign banks and 3 Chinese commercial banks. By the end of the year, the number of users had increased to 338, and the rental fee for each household was 150 yuan per year. In the same year, British companies such as China Toyo Telephone also established telephone companies in Shanghai.

Huang Shiquan recorded in “Songnan Dream Video Recording”: “The method is to erect wooden poles along the way and tie two lead wires to them, which is no different from the telegraph. However, the mechanism is completely different. The method of transmission does not use letters to assemble it, but only The message must be communicated to the end of the line, just like talking in a room. According to the cloud, within twelve o’clock, it can be transmitted to the five continents of the earth.”

The significance of the installation of these local telephones is different from the point-to-one intercom telephones of the previous steamship merchants. These 25 places with telephones can communicate with each other, and the transfer is realized through the telephone exchange. There are many connections in front of each operator. board, when the caller makes a call, the corresponding socket will light up, and then the operator can pick up the phone and ask you where to call. If the phone number is within the range of his management, he will insert the line plug into the corresponding socket. jack, then the called party’s home phone starts to ring, and the two parties can talk.

Shenzhen EAST LINE are the OME landline telephone manufacturer.

5. The development of China’s telephone industry in the Qing Dynasty and the Republic of China

In 1900, under the promotion of the Qing government, Liu Kunyi, the governor of Liangjiang and the minister of Nanyang, “due to the defense and martial law, the vast area of the province, the civil and military personnel were stationed far away, and when there was an incident, the business was spread, and the delay was carefully considered.” Set up a telephone and use a wire to convey messages, hoping to respond well.” He established the Jiangnan Electric Power Bureau in Rundli, Nanjing, and set up a telephone exchange (also known as the “Telephone Central Office”). He initially set up a 50-door magnet manual switchboard and installed 16 single machines, all of which were used by the official residence. .

In 1903, the Tianjin Telephone Bureau was established.

In 1904, the Beijing government-run telephone exchange was established.

In February 1907, the State Administration of Telecommunications of the Ministry of Posts and Telecommunications of the Qing government established the Shanghai Telephone Bureau in Xinquanli Street outside the East Gate of Shanghai South City based on the commercial telephone of 1902. It rented three private houses as office rooms, with a total of It had 19 employees and had 97 users when it opened, breaking the situation in which foreign companies had monopolized Shanghai’s telephone communications industry since the establishment of the foreign telephone company in 1882.

Telephones have limitations such as a limited transmission distance, which can only “reach a distance of sixty miles”, and “a person with many languages cannot understand many languages”, so there is a long way to go for improvement. Therefore, after the telephone entered China, it did not spread to all parts of the country as quickly as the telegraph did.

In 1889, Peng Mingbao, who was in charge of Anqing’s telegraph business in Anhui at that time, designed and manufactured my country’s first telephone, named “Microphone”, with a communication distance of up to 300 miles.

In 1929, a long-distance line was laid between Nanjing and Shanghai. A pair of lines passed through Zhenjiang, Wuxi, Suzhou, Kunshan and other places. The call was in one place and stopped in other places. Later, a pair of lines were added directly to Shanghai. To make a long-distance call, you must first dial the record number and register. There are two types: urgent and regular. Because there are too few lines, there is an unwritten rule: business people give way to military people, military people give way to air defense, and small officials give way to big officials. When Chiang Kai-shek calls, all people give way except air defense.

6. The development of telephone after the founding of the People’s Republic of China

In 1949, China’s telephone penetration rate was only 0.05%, and there were only 260,000 telephone users.

In 1970, Denmark first used the F-68 digital push button dialing telephone, replacing the rotary dial type.

In 1978, China’s telephone capacity was 3.59 million, users were 2.14 million, and the penetration rate was 0.38%, less than 1/10 of the world level.

In 1982, China’s first 10,000-door program-controlled telephone exchange, the Japanese F-150, was put into use in Fuzhou. This work began at the end of 1979. During the equipment selection stage, my country successively cooperated with 8 companies including Fujitsu, NEC, Ericsson, and Philips. Negotiated with manufacturers and conducted a short-term equipment selection inspection in Japan. The Fujian Provincial Post and Telecommunications Administration signed an introduction contract with Fujitsu on December 24, 1980. The local telephone equipment was shipped from Yokohama, Japan on January 30, 1982. It was installed on April 12 and officially opened at 0:00 on November 27.

In 1985, Shenzhen issued my country’s first set of phone cards, with a total of 3 cards and a face value of 87 yuan.

The initial installation fee for installing a local telephone in 1991 was 1,500 yuan.

In 1995, the initial installation fee for local telephone calls was 3,500 yuan.

In March 2003, the number of fixed-line users reached 225.626 million, and the number of mobile phone users reached 221.491 million. The number of mobile phone users is about to equal that of fixed-line users.

Shenzhen EAST LINE’s annual capacity of landline telephones is around 3 Million units for home, office, hotel, schools etc.

Slim Corded Telephone Trim Line Phone With Hard Shell

Categories: Industrial News

Fixed Landline Telephone History in China

In China, the telegraph and the telephone appeared at about the same time. After the telegraph line was built, the telephone also entered China. In many cases, telephone lines and telegraph lines were shared, and the development trajectories of the two were almost parallel. They were not It took many years after the telegraph was introduced to China before more advanced telephones slowly appeared. The phone number in this issue refers to a landline phone, also known as a “landline”, not a mobile phone (cell phone).
Shenzhen EAST LINE are the professional OEM landline telephone manufacturer.

Multi-feature Big Buttons Analog Telephone

1. Invention of telephone

In 1861, a German teacher invented the original telephone, which used the principle of sound waves to communicate with each other over short distances, but it was not put into actual use.

There has always been controversy about the inventor of the telephone. Some say it was Antonio Meucci, another said it was Bell, and another said it was Elisha Gray. There are many such things. The most famous one is Newton and Leibniz’s theory of micro-organisms. In the story of points, the main controversy is Meucci and Bell.

In 1849, the 41-year-old Meucci accidentally discovered that wires could transmit some sounds during an electroshock treatment. Then he made a simple sound transmission system. In 1860, the 52-year-old Meucci demonstrated this system to the public and An introduction to the invention was published in an Italian-language newspaper in New York, when his rival Alexander Bell was only 13 years old. Because he was too poor to pay the patent maintenance fee, he sent the model and technical details to the Western Union Telegraph Company in the hope of commercial use, but nothing happened.

On February 14, 1876, Bell, who shared a laboratory with Meucci, applied for a telephone patent to the U.S. Patent Office, and the application was approved on March 3.

However, whether Bell independently invented the telephone, improved the sound transmission equipment, plagiarized Meucci, or used different principles, please stay calm. When science and technology develop to a certain level, the same creation and creativity It occurs in many places, which is very common.

Telegraph lines were originally used to transmit telephone signals, but the noise interference caused by such lines was very large, so people were not allowed to improve the communication lines. In 1883, a line using a second wire as a loop appeared, which greatly reduced the noise interference in telephone communications.

 

2. The origin of the name “telephone”

In 1796, Hughes proposed a method of using a microphone to relay voice messages. Although this method was not very practical, he gave this method of communication a name: Telephone, which is still used today.

The Chinese word “telephone” is a Chinese word created by Japan. In fact, there are many Chinese names translated in Japan. In addition to telephone, the most famous one is the philosophical term “metaphysics”. Telephone is the free translation of the English word “telephone”. The Chinese transliterated this English word and translated it as “telephone”.

In the early 20th century, a group of foreign students from Shaoxing in Japan jointly wrote a reply to their hometown, which introduced the modernization situation in Japan in detail. Lu Xun was also listed among them. When the letter mentioned “telephone”, he specifically explained: “With electrical appliances, To convey words, the Chinese translated it as “telephone”, which is not as good as “telephone”. Gradually, it was called telephone. For a period of time, the two terms “telephone” and “telephone” were commonly used. Later, “telephone” “Wind” slowly disappears.

3. Chinese people came into contact with telephones for the first time

In 1876 (the second year of Guangxu), Ningbo customs official Li Gui was ordered to go to the United States to participate in the “World’s Fair” held in Philadelphia. He saw a telephone that could transmit messages, and wrote it in his book “A New Record of Traveling Around the World”. In the book, Li Gui is the first Chinese to see a telephone for which historical data are available.

In this book, he also made detailed records of the U.S. Postal Service and suggested that the Qing Dynasty also open a Chinese postal service. His insights were praised by Li Hongzhang, and he was subsequently ordered to draft the “Translation and Drafting of the Postal Service’s Rules for Sending Letters”, which included ten The specifications, features, rates, etc. of several types of mail are specified in detail. When Kang Youwei was 22 years old, he read the newly published “New Records of Around the Earth”.

In 1877, the year after Bell invented the telephone, a Chinese was fortunate enough to use a telephone. This Chinese was named Guo Songtao, who was the first minister of the Qing Dynasty to Britain.

On October 16, 1877, Guo Songtao was invited to visit a power plant near London, England. During the visit, the owner specifically asked him to experience the telephone, which had recently been introduced to the United Kingdom from the United States. One end of the telephone was installed upstairs and the other end was installed downstairs. , Guo Songtao asked Zhang Deyi, the translator of the Chinese Embassy, to go downstairs to answer the call, while he made the call upstairs.

Guo: “Did you hear that?”

Zhang: “Yes.”

Guo: “Are you aware?”

Zhang: “Yes”

Guo: “Please count the numbers.”

Zhang: “One, two, three, four, five, six, seven”

This was the first time for Chinese people to use the telephone. Guo Songtao wrote down his experience of using the telephone in his diary: “There are many languages and there are many that cannot be understood, but this number is distinct.” He called it a “sound reporting machine”. Guo Songtao will What he saw along the way was recorded in his diary “Shi Xi Ji Cheng”, advocating that China should study and learn from the advanced technologies and systems of the West. After the book was sent to the Prime Minister’s Office, it was attacked and cursed by diehards. It was not made public until Guo Songtao’s death. issued.

As the professional OEM fixed telephone manufacturer, Shenzhen EAST LINE can supply lots of different kinds of corded landline telephones for home, office, hotel and public places.

Basic Trimline Corded Phone Hotel Telephone

3. Magnet Telephone

Bell’s phone is a magnet phone. The so-called magnet phone is also called a hand-crank phone or a crank phone. There is a crank on the left side of the phone. Before using the phone, you need to crank it to charge the battery. The general working principle is: When the speaker picks up the phone and speaks into the microphone, the vibration of the vocal cords forms sound waves, which act on the microphone, causing the carbon particles in the metal box of the microphone to become loose and tight – the resistance becomes large and small – circuit The current is strong and weak. , the voice current is transmitted along the line to the receiver of the other party’s phone. The magnetism of the electromagnet in the receiver becomes stronger and weaker – the magnetic force on the thin iron sheet becomes stronger and smaller – causing the thin iron sheet to vibrate and emit sounds that are connected to the speaker. Same sound.

Categories: Company News, Industrial News

During this cold winter, we (Shenzhen East Line Communication Tech Co., Ltd.) have to thank you for your hard work and kind cooperation in 2023, to all our customers, partners and suppliers.

Merry Christmas and Happy New Year to you and your family.

2023 telecom industry outlook

Five key trends shaping the telecom landscape

In the year ahead, telecommunications companies will be focused on delivering advanced connectivity and higher performance to customers while reinforcing value and competitiveness. Our 2023 outlook examines five trends shaping telecom industry growth and business strategy, from 5G monetization to edge computing to an increasing focus on sustainability.

Preparing for a strong, resilient future

Telecom industry growth continues to be driven by the continued importance of connectivity, bringing both opportunities and challenges for communications service providers (CSPs). This year’s telecom outlook explores how CSPs are delivering value to consumer and enterprise customers with bundled services and connectivity options like 5G fixed wireless access (FWA) and fiber, as well as their role in meeting the growing demand for edge computing. We’ll also consider how CSPs may want to balance pricing decisions with the need to accelerate deployment of infrastructure like fiber networks, while attending to the growing urgency to reduce resources, waste, and emissions from network operations, upgrades, and deployments. As connectivity works its way into more of the world, it may be more imperative than ever to balance costs with the needs of households, businesses, communities, and the environment.

Some of the specific themes we see playing a critical role in 2023 and beyond include the following:

  • The bundle battle: Add more value for cost-conscious consumers. For individuals and families, connectivity is important. Yet, consumers often have cost constraints that can limit their options or drive them to seek the best service at the lowest price. To offer more value to consumers, many CSPs are bundling mobile and home internet access, offering connectivity options like fiber and 5G FWA, and partnering with entertainment services to include subsidized or free subscriptions.
  • Fixed wireless access surges, but will it endure? As part of this “bundle battle,” 5G FWA has enjoyed substantial growth. This type of connectivity can provide strong reliability, but some questions remain about how much it can scale. As more people use 5G services, and if more bandwidth-intensive “killer apps” emerge, the limits of 5G FWA could be exposed. However, market dynamics and next-gen technology solutions could overcome these challenges. https://www.oemtelephone.com/product-category/fixed-wireless-phone/
  • What enterprises want from 5G edge. For enterprise customers, the need to cut costs, automate capabilities, and support innovation is driving interest and adoption of edge computing. CSPs will likely need partners to develop and deploy edge solutions, requiring more cooperation with erstwhile competitors.
  • Joint ventures accelerate deployment of fiber networks. Many of the connectivity solutions we cover rely on fiber networks. With high demand, strong competition, and the need to optimize costs and risk, more CSPs are partnering with private investors to accelerate deployment of fiber networks.
  • Increase the focus on sustainability. In doing so, these partnerships can support existing customers while extending further into underserved communities, helping to narrow the digital divide—the gap between those who have access to modern information and communication technologies and those who don’t. This aspect tugs at the broader economic imperative of connectivity: more bandwidth, more equally distributed, enabling greater access to education and opportunity.

Shenzhen East Line are always working hard to supply you the best telecom devices with high quality, new technology and advanced features.
2023 year will pass soon, but we are ready to be work together with you in 2024 new year.