What is Circuit Switched FallBack (CSFB) ? Circuit Switched FallBack (CSFB) is a technology used in 4G LTE whereby voice and SMS services are delivered to LTE devices through the use of GSM or another circuit-switched network. Circuit Switched FallBack is needed in some networks because LTE is a packet-based all-IP network that cannot support […]
4G LTE Cells, Sectors and Antenna Beamforming Why Beamforming in Cellular Radio Design? In cellular radio network design, a simple hexagon is used to represent a complex object: the geographical area covered by cellular radio antennas. These areas are called “cells.” This shape lets us picture the cellular idea on a map, because when displaying […]
Beamforming and 8T8R LTE Radios New technologies, new techniques One of the early lessons learned by operators deploying LTE TDD was that of implementing beamforming with 8T8R (8 transmit, 8 receive) radio modules from the beginning. China Mobile is utilizing beamforming with 8T8R within the majority of its base stations from day one, a consequence […]
RF Connectors used for LTE Base Stations Specialised connectors are used for 4G & 5G LTE Base Stations. Key requirements include ability to handle high RF power levels as well as Low-PIM (Phase InterModulation) With all RF connectors the safe power handling is determined by the heating and subsequent oxidation of the centre ‘pin’ for […]
What are ITU Regions? The International Telecommunication Union (ITU), in its International Radio Regulations, divides the world into three ITU regions for the purposes of managing the global radio spectrum. Each region has its own set of frequency allocations, the main reason for defining the regions. These regions are used to define the frequency bands […]
Frequency Reuse Plans in 4G / LTE 4G LTE cellular systems address the need of high capacity Wireless Internet services to mobile and fixed devices. Frequency Reuse planning is essential to allow seamless coverage and efficiency use of the available spectrum. 3GPP Long Term Evolution (LTE) is a standard for wireless communications to achieve high […]
Passive Intermodulation (PIM) as a source of 4G/LTE interference What is PIM? One cause of self-disturbance in LTE Networks is Passive Intermodulation (PIM). PIM is interference resulting from the nonlinear mixing of two or more frequencies in a passive circuit. If the interference coincides with a network’s base receive frequencies, it can cripple network performance and throughput. Possible PIM […]
Reducing Passive Inter-Modulation Passive Inter-Modulation, also known as PIM is a problem that can affect FDD (Frequency Division Duplexing) LTE systems. Explaining the PIM Problem: Passive Inter-Modulation (PIM) products are caused by passive components such as duplexers, connectors, cables, and antennas. These components are nonlinear and create intermodulation products that can leak into the receive […]
LTE Advanced Pro and the Roadmap to 5G The 3GPP standards define the roadmap from LTE through LTE Advanced Pro to 5G, lead by the major players in the cellular industry – operators and vendors together. Evolution of LTE to 5G LTE is evolving from LTE, LTE-Advanced (LTE-A), LTE Advanced Pro (LTE-A Pro) and up […]
Demonstrating 150Mbps 4G/LTE-A Connection to a Desktop LTE CPE: Throughput testing of LTE-A Closed Private 4G Network using 2×2 MIMO, 20MHz channel in Band 3. Shows 150Mbps DL & 42Mbps UL between PC web browser connected through Desktop Cat4 LTE CPE and server. A video of the demonstration with some explanation and results is here: […]