A brief introduction to heterogeneous networks (HetNets) and its challenges

The demand for smart phones and for smart applications has increased at a high rate in recent years. The data traffic in general has been increasing significantly from year to year. Conventional deployments of cellular networks are reaching their limits for point to point transmission link with the increase in data rates brought by new technologies as High Speed Packet Access (HDPA), 3xEV-DO and the Long Term Evolution (LTE). Although these improvements are significant for users in good coverage and in lighted loaded systems, they do not translate into improvements of the system efficiency in bits per second per Hertz. Gains for the system are achieved through the increase in the number of base stations or relay nodes. This paper describes the 3GPP concept of Heterogeneous Networks. The paper highlights the need to employ advance techniques of interference management and resource sharing in networks composed of different transmission power nodes (base stations and relay stations) and the possible gains in having those nodes.