Another technique used for increasing the data rate is massive MIMO (multiple-input multiple-output).Each cell will have multiple antennas communicating with the wireless device, received by multiple antennas in the device, thus multiple bitstreams of data will be transmitted simultaneously, in parallel. They are only a few inches (several centimeters) long. Millimeter wave antennas are smaller than the large antennas used in previous cellular networks. Millimeter waves have shorter range than microwaves, therefore the cells are limited to smaller size The waves also have trouble passing through building walls.
Like existing cellphones, when a user crosses from one cell to another, their mobile device is automatically "handed off" seamlessly to the antenna in the new cell. The local antennas are connected with the telephone network and the Internet by a high bandwidth optical fiber or wireless backhaul connection.
All the 5G wireless devices in a cell communicate by radio waves with a local antenna array and low power automated transceiver (transmitter and receiver) in the cell, over frequency channels assigned by the transceiver from a common pool of frequencies, which are reused in geographically separated cells. Analog signals representing sounds and images are digitized in the phone, converted by an analog to digital converter and transmitted as a stream of bits. Ping was 25 milliseconds.įive companies sell 5G radio hardware and 5G systems for carriers: Huawei, ZTE, Nokia, Samsung, and Ericsson.ĥG networks are digital cellular networks, in which the service area covered by providers is divided into a mosaic of small geographical areas called cells. Download speeds in Chicago were from 80 to 900 Mbps. Verizon opened service on a very limited number of base stations in the US cities of Chicago and Minneapolis using 400 MHz of 28 GHz millimeter wave spectrum. 260,000 signed up in the first month and the goal is 10% of phones on 5G by the end of 2019. They are using 3.5 GHz (sub-6) spectrum and tested speeds were from 193 to 430 Mbit/s down. In South Korea, SK Telecom claimed 38,000 base stations, KT Corporation 30,000 and LG U Plus 18,000 of which 85% are in six major cities. The first fairly substantial deployments were in April 2019.
It follows 2G, 3G and 4G and their respective associated technologies (such as GSM, UMTS, LTE, LTE Advanced Pro, etc.). Others may reserve the term for systems that meet the requirements of the ITU IMT-2020, which represents more nations. The industry association 3GPP defines any system using "5G NR" (5G New Radio) software as "5G", a definition that came into general use by late 2018. 5G is generally seen as the fifth generation cellular network technology that provide broadband access.
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