Small cells and distributed antenna systems (DAS) are two methods of enhancing network coverage and capacity, particularly indoors, for 5G networks[2]. Both systems use individual antennas placed at low elevations to improve wireless service for users[2].
**Small Cells: Small cells are low-powered radio access nodes that can increase the density of a cellular network[1][3]. They are essentially mini base stations that operate on a variety of frequencies and can be deployed indoors or outdoors[3]. Indoor small cells are typically small, about the size of a pizza box, and can be installed on ceilings and walls to boost the radio frequency signal strength of cellular networks[3]. Small cells are particularly useful for supporting wireless carrier deployments of spectrum at high-band (millimeter wave) frequencies, where traditional tower sites may not be as effective due to the shorter distances these signals travel[2]. They can also be used in private 5G networks for business applications, offering a secure, reliable, low-latency, and high-speed private network[3][9].
**Distributed Antenna Systems (DAS): A DAS is a wireless infrastructure technology designed to enhance the coverage and capacity of cellular networks[4]. DAS overcomes the challenges of shorter wavelengths and high data demands of 5G, especially in indoor locations where high towers are not practical[4]. DAS antennas, also called base stations, are small and can be placed throughout a building to provide a strong 5G network[4]. Many enterprises use DAS to carry a cellular signal from a central source throughout a building, and small cell networks can supplement these systems for improved indoor mobile coverage[3].
**Indoor Coverage: In-building wireless boosts cellular performance across any frequency band, even for low-band frequencies that can penetrate buildings[6]. A well-known statistic in the wireless industry is that 80% of cellular connections begin and end indoors[6]. Early adopters of 5G have rated indoor coverage as twice as important as 5G speeds or device battery life[6]. Traffic congestion, which typically happens indoors, has resulted in more spectrum bandwidth deployed at a single cell[1]. Site densification has been proven to be a better solution, but requires tactful site planning and design to avoid inter-cell interference issues[1].
Citations:
[1] https://leadcom-is.com/solutions/coverage-enhancement-solutions/small-cells/
[2] https://dgtlinfra.com/what-are-small-cells-distributed-antenna-systems-das/
[3] https://www.techtarget.com/searchnetworking/tip/Indoor-5G-gets-a-boost-as-small-cells-come-to-the-rescue
[4] https://cencepower.com/blog-posts/5g-das
[5] https://www.networkcablingservices.com/5g-and-das-what-the-future-holds-for-indoor-networks/
[6] https://www.5gtechnologyworld.com/how-distributed-antenna-systems-bring-cellular-indoors/
[7] https://www.ericsson.com/en/small-cells/indoor-coverage
[8] https://www.sannytelecom.com/what-is-a-5g-das-antenna/
[9] https://www.waveform.com/a/b/guides/5g-das