We can anticipate that number of wireless devices, applications, and services of 5G will be greater than those of 4G, and so will be the traffic flow. While there will be 20 billion handheld or personal mobile devices by 2025, the Internet of Things paradigm is envisioned to deploy 212 billion smart entities by then. Moreover, according to statistical analysis and predictions by the International Telecommunication Union (ITU), the global mobile traffic per month is expected to be 543EB by 2025 and 4394EB by 2030. To sustain this unprecedented growth, cellular evolution is quickly progressing towards the 5G era. 3GPP standardization played a vital role in popularity and success of Long-Term Evolution (LTE) communications. Recently, 3GPP endorsed a tentative timeline for the 5G standardization, with an initial focus on high-frequency bands. The vast availability of underexploited mm-Wave spectrum (6 GHz to 300 GHz) promises to bridge the gap between bandwidth limitations of current beachfront spectrum and the increased bandwidth appetite of the wireless industry.

5G techniques are dynamic, self-configured, and multi-hop networks, which are formed without any control and infrastructure. The analyses about the availability of routes in this network can change because of the mobility of nodes. The topology of this network is not fixed and may change frequently. Some of the limitations of this kind of network are power consumption, reduced bandwidth, limited channel capacity, etc. Due to the dynamic topology, the routes are not fixed, and they change frequently with the node movement. Therefore, the routes will be broken, and proper route maintenance is required whenever the routes are broken. There are various routing protocols used for establishing an appropriate route mechanism for nodes.

Within the broad range of research challenges for 5G signal processing techniques, this Special Issue aims to present recent advances in signal processing for communication with an emphasis on signal processing techniques that may be relevant for emerging 5G networks. This Special Issue aims to bring together researchers and practitioners to foster cutting-edge technologies, novel research, and tutorial overviews on topics related to the future development of 5G. We welcome original research and review articles.

Potential topics include but are not limited to the following:

• Transmission waveform, modulation, processing, protocol, algorithms, and coding techniques for 5G
• Network planning and signal processing techniques for 5G transmission
• Cognitive spectrum, location-based authentication usage, and allocation for 5G
• 5G user-centric network architecture, optimization, and new network topology with high mobility support
• Data acquisition, signal processing, data analysis, and algorithms for 5G
• Source enumeration and direction-of-arrival estimation and intelligent user interfaces
• Signal processing techniques for sensing and inference in 5G sensor networks
• Machine learning empowered signal processing for context-aware 5G applications
• Massive MIMO for 5G: theory, implementation, and prototyping
• Advanced transceiver designs for new signal processing technologies for 5G
• Sensing and signal processing for 5G-enabled wearable devices and man-machine interface.
• Radio-resource management and optimization in 5G networks
• Signal and image processing for medical applications
• Application in 5G systems with advanced signal processing approaches