4g and 5g bands

4G (LTE) and 5G (NR - New Radio) mobile communication technologies:

4G (LTE) Bands:

1. Frequency Range:
   • 4G operates in various frequency bands, including:
     • Sub-1 GHz bands (e.g., 700 MHz, 800 MHz, 900 MHz)
     • 1-2 GHz bands (e.g., 1700 MHz, 1800 MHz, 1900 MHz)
     • 2-3 GHz bands (e.g., 2300 MHz, 2500 MHz)
     • 3-4 GHz bands (e.g., 3500 MHz, 3700 MHz)
2. Duplexing:
   • 4G uses both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) for spectrum allocation.
   • In FDD, separate frequency bands are allocated for uplink and downlink communication.
   • In TDD, the same frequency band is used for both uplink and downlink, with time slots allocated for each.
3. Carrier Aggregation:
   • 4G supports carrier aggregation, allowing multiple frequency bands to be aggregated for increased data rates.
   • Different LTE bands can be combined to achieve higher bandwidth and improved spectral efficiency.

5G Bands:

1. Frequency Range:
   • 5G operates in a broader frequency spectrum, including:
     • Sub-1 GHz bands (e.g., 600 MHz, 700 MHz)
     • 1-6 GHz bands (e.g., 3.5 GHz, 3.7 GHz, 4.5 GHz)
     • mmWave (millimeter-wave) bands (e.g., 24 GHz, 28 GHz, 39 GHz)
2. Duplexing:
   • 5G continues to use both FDD and TDD, but the focus has shifted towards TDD for many frequency bands.
   • TDD is more prevalent in higher-frequency bands, especially in the mmWave range.
3. Carrier Aggregation:
   • 5G expands on carrier aggregation techniques, allowing aggregation across a wider range of frequency bands.
   • Carrier aggregation in 5G enables operators to utilize multiple bands simultaneously, improving data rates and network efficiency.
4. Dynamic Spectrum Sharing (DSS):
   • DSS is a technology introduced in 5G that enables the simultaneous operation of LTE and 5G NR within the same frequency band.
   • DSS allows for a smoother transition from 4G to 5G without the need for dedicated frequency bands.
5. Massive MIMO and Beamforming:
   • 5G utilizes Massive Multiple Input Multiple Output (MIMO) technology in the mid and high-frequency bands.
   • Beamforming is employed to focus radio waves in specific directions, enhancing signal quality and coverage.
6. mmWave Bands:
   • 5G introduces the use of mmWave bands, which offer very high data rates but have shorter propagation distances and are more susceptible to atmospheric absorption.
   • mmWave bands are typically used in dense urban environments and for specific applications like fixed wireless access.
7. Frequency Ranges for Specific Use Cases:
   • Different frequency ranges in 5G are often associated with specific use cases. For example:
     • Sub-1 GHz for wide-area coverage and IoT applications.
     • Mid-band frequencies for a balance between coverage and capacity.
     • mmWave for ultra-fast data rates in specific applications.

It's important to note that the availability of specific frequency bands can vary by region, and regulatory bodies allocate spectrum differently in different parts of the world. The technical considerations for each band include factors such as propagation characteristics, coverage, and the ability to support different use cases, influencing the deployment strategy for mobile operators.