مشاهدة المرفق 602518
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Radio wave frequencies range from Extremely Low Frequencies (ELF) 3 kilohertz (kHz) to Extremely High Frequencies (EHF) 300 gigahertz (GHz) as shown in infographic above (larger version at bottom). EHF are often called the millimeter band because its wavelengths range from 1 to 10 mm. Wavelengths in and around this band are called millimeter waves (mmW).
Worldwide, 5G will use spectrum in the existing 4G LTE frequency range 600 MHz to 3 GHz (Ultra High Frequency, UHF) and even up to 6 GHz, as well as millimeter wave bands 24 to 86 GHz (Super High Frequency to Extremely High Frequency). UHF spectrum is also being used by some Carriers for 5G. Ultra High Frequency (UHF) band has a frequency range of 300 MHz to 3 GHz. It is already being used since years in many other applications such as TV broadcasting, cordless phones, Wi-Fi, GPS, and Bluetooth.
5G Frequency Spectrum Usage By 4 Major USA Carriers:
The following are preliminary disclosed 5G frequencies and subject to change in future:
- T-Mobile: 600 MHz low-band spectrum as well as mid-band spectrum. T-Mobile's 28 Ghz mmWave frequency network will be combined into a wider 5G setup with a lower-band 600 Mhz spectrum it aims to launch in 30 cities later in 2019.
- Verizon: 5G Ultra Wideband network uses Super High Frequency (SHF) at 28 GHz and Ultra High Frequency (UHF) at 39 GHz. Both are high-band millimeter wave (mmWave) frequencies.
- AT&T: Plans to use millimeter wave spectrum (Extremely High Frequencies, EHF) for densely populated areas like downtown core of major cities and mid to low-spectrum for suburban and rural areas. Its current 5G-E frequencies are same as its 4G LTE frequencies. Its 5GE is not AT&T's real 5G network. It serves as a foundation for the AT&T's true 5G service, which will arrive later.
- Sprint: 800 MHz, 1.9 GHz and 2.5 GHz. It is using mid-frequency band 41 for its 5G service. It is the only US carrier that does not use a high-frequency band. Its 2.5 GHz frequency provides ultra-fast transfer speeds characteristic of 5G.
Wavelength:
The word, "wavelengths" stated in table below may seem intriguing so let us give you a brief overview of what it means. Wavelength is inversely proportional to frequency. Therefore, higher frequencies have shorter wavelengths. For example, 15 Hz (low frequency) has a wavelength of over 3,000 miles, while 300 GHz (high frequency) is only 1 mm. Therefore, high frequencies can travel at faster speeds but can go only short distances. On other hand, low frequencies travel at slower speeds and can go longer distances.
This is why a lower number 3G frequency example 800 MHz UHF band network phone (providing slower downloads, higher latency) would require a cell transmitter or cell tower within 2 miles to connect whereas a higher number 5G frequency example 39 GHz EHF band network phone (providing faster downloads, lower latency) would require a cell transmitter within each block or roughly between every six houses. Both types will require a
cell phone signal booster for cell phones to connect to network, if those signals are too weak to penetrate the house or building walls when located inside.
| ELF | EXTREMELY LOW FREQUENCY
Frequency: 3 KHz to 30 KHz
Wavelength: 100 km to 10 km |
|---|
| LF | LOW FREQUENCY
Frequency: 30 KHz to 300 KHz
Wavelength: 10 km to 1 km |
|---|
| MF | MEDIUM FREQUENCY
Frequency: 300 KHz to 30 MHz
Wavelength: 100 km to 10 km |
|---|
| HF | HIGH FREQUENCY
Frequency: 3 MHz to 30 MHz
Wavelength: 100 m to 10 m |
|---|
| VHF | VERY HIGH FREQUENCY
Frequency: 30 MHz to 300 MHz
Wavelength: 10 m to 1 m |
|---|
| UHF | ULTRA HIGH FREQUENCY
Frequency: 300 MHz to 3 GHz
Wavelength: 1 m to 100 mm |
|---|
| SHF | SUPER HIGH FREQUENCY
Frequency: 3 GHz to 30 GHz
Wavelength: 100 mm to 10 mm |
|---|
| EHF | EXTREMELY HIGH FREQUENCY
Frequency: 30 GHz to 300 GHz
Wavelength: 10 mm to 1 mm |
|---|
مشاهدة المرفق 602519
مشاهدة المرفق 602521
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