Hello, community friends!
Starting today, I will continue to share my knowledge of HCIA-LTE on the forum. If you are interested in the content, please join us and let us learn about HCIA-LTE. First, let's look at the evolution process of cellular networks.
Evolution of cellular networks
LTE is a milestone in the history of communications. It represents the unification of global systems while reducing global network deployment and terminal costs, which is a boon for operators and equipment manufacturers.
Mobile networks have been evolving for many years. The initial systems, which are referred to as "First Generation" were launched commercially at the end of the 1980s. Pressure for greater capacity, more security, and roaming saw these replaced with "second Generation, and more recently "Third Generation" solutions. Today, the growth in mobile. Broadband has promoted the development of 4G or "Fourth Generation" systems.
1st Generation mobile Systems used analog modulation techniques. These analog systems were proprietary and based on Frequency Modulation. For this reason, they all lacked security, any meaningful data service, or international roaming capability. The main commercial systems deployed around the world included AMPS, TACS, and ETACS.
AMPS
The first AMPS system appeared in 1976 in the USA. Its initial commercial mouths including weak security features made the System prone to hacking and handset cloning.
TACS
The European version of AMPS but with slight modifications including its operation mouths on different frequency bands. It was mainly used in the UK, as well as part of Asia.
FTACS
An improved version of TACS. lt enabled a greater number of channels and mouths, therefore, facilitating more users.
3GPP Evolution
3GPP (3rd Generation Partnership Project)
A project founded in 1998, aiming to expedite the development of open, globally accepted technical specifications for the Universal Mobile Telecommunications System (UMTS), including the WCDMA and TD-SCDMA specifications.
The development of GSM, GPRS, EDGE, UMTS, HSPA, and LTE, as well as the strategy for future mobile networks, has been coordinated and planned by the various parties that sit within the 3GPP working groups. This development roadmap is based on a series of specification releases. The diagram shows the key release milestones. These started with the introduction of GPRS in Release 97 and chart the evolution of 3GPP networks up to the introduction of LTE and beyond.
Homogeneous network
A typical homogeneous cellular network consists of the same type of base stations, typically macro base stations and a number of columns of mobile terminals. These macro base stations have similar transmit power, antenna pattern, and receiver noise levels.
The location of the macro base station needs to be determined through careful network planning, and the parameters of the macro base station need to be properly configured to maximize the network coverage and control the mutual interference between the base stations. When service requirements increase or the RF environment changes, the network needs to rely on cell splitting or new carriers to overcome the limitations of capacity link budget, and maintain a consistent user experience. This repeated deployment process is complex. In addition, in a high-density urban environment, it is difficult to find a new base station area that can be used for heat dissipation. Therefore, operators need a more flexible deployment model to improve network performance at a low cost.
Heterogeneous network
To overcome the problems of homogeneous networks and greatly improve network performance, 3GPP introduces a heterogeneous network deployment mode in LTE-A. A heterogeneous network is a network in which conventional macro base stations and a series of low-power nodes are deployed. A low-power node deployed in a blind area of a macro cellular network can increase network coverage. A low-power node deployed in a hotspot cell of a macro cellular network can shorten the distance between a network and a terminal user, thereby enhancing link quality and improving system capacity.
Therefore, LTE is an evolution of 3GPP-dominated wireless communications technologies.
LTE technical objectives
This is the evolution of cellular networks. The purpose of the evolution is to meet the ever-increasing service requirements. Therefore, the evolution of the network will not stop.
Welcome to read and learn. I will introduce the EPS Architecture in the next post.
