Rapid Prototyping and Validation of FS-FBMC Dynamic Spectrum Radio With Simulink and ZynqSDR

Abstract

This paper presents the research carried out in developing and targeting a novel real-time Dynamic Spectrum Access (DSA) Frequency Spread Filter Bank Multicarrier (FS-FBMC) transmitter prototype to programmable 'ZynqSDR' Software Defined Radio (SDR) hardware, and introduces a series of experiments used to validate the design's 'cognitive' DSA capabilities. This transmitter is a proof of concept, that uses DSA techniques to enable Secondary Users (SUs) to access the band traditionally used for FM Radio broadcasting (88-108 MHz), and establish data communication channels in vacant parts of the FM Radio Primary User (PU) spectrum using a multicarrier modulation scheme with a Non Contiguous (NC) channel mask. Once implemented on the hardware, the transmitter is subjected to various FM Radio environments sampled from around Central Scotland, and it is demonstrated that it can dynamically adapt its NC transmitter mask in real time to protect the FM Radio signals it detects. A video is presented of this dynamic on-hardware spectral reconfiguration, and the reader is encouraged to view the video to appreciate the responsiveness of the design. An investigation into potential FBMC guardband sizes is carried out, with initial findings indicating a guardband of 200 kHz (either side of an FM Radio station) is required in order to prevent interference with the PUs. This paper also demonstrates the capabilities of the MATLAB R / Simulink R Model Based Design ZynqSDR workflow, and provides a case study and reference design that we feel other researchers working in this field can benefit from.

Spectrum Occupancy Model Based on Empirical Data for FM Radio Broadcasting in Suburban Environments

“…where P av,c,τ is the averaged power of channel c at time instance τ and is defined as Second, we initialize the search for the decision threshold by randomly picking up a decision threshold γ to substitute in Equation (11), and make a plot of occupation percentage from Equation (10) as a function of power level. Note that the plot contains several curves, each of which represents each selected channel from Section 4.2.2.…”

“…In this particular case, the channels c with an A c , estimated by Equation (8), of 12 were classified as the full-time case, while the channels c with an A c between 1 and 11 were classified as the part-time case. In a full-time case, the black pixels represented on Channel 6,11,34,35,37,43,44,68,69, and 81 overall sampling times. In a part-time case, the alternating of black and white pixels represented on Channel 4, 9, 18, 31, 60, 61, 63, 66, and 79 overall sampling times.…”

“…To achieve the appropriate decision threshold, we accessed the prior knowledge of noise properties and the environment through the duty cycle curves of all activities' channels, including strong, good, weak, and no activities. We plotted the D c curve of each selected channel by substituting the power signals P s c,τ into Equation ( 10) and by substituting a decision threshold into Equation (11). These curves' values monotonically decreased from 100 to 0% when substituting the γ from the lower bound to the upper bound.…”

“…However, it is not guaranteed that digital radio broadcasting will be more popular with the audiences in the future. Some countries have delayed their plans to transit away from analog FM radio broadcasting to DAB, such as Sweden, Denmark, Thailand, and UK, because most people, who listen to radio are of the generations familiar with analog radio [11]. The government of each nation hesitates to migrate from analog FM radio to digital radio because a large budget is required for upgrading all transmitters and receivers.…”

“…Reference [12] proposed the theoretical technique to access the FM radio spectrum for facilitating the communication between the secondary users. Later, the technique was implemented in Reference [11], where the prototype with Frequency Spread Filter Bank Multicarrier (FS-FBMC) transmitters was designed. Their experimental results pointed out that the FBMC technique can be developed in the future into an SU IoT Wide Area Network broadcast channel, which has many applications, such as energy smart grid balancing, rural communities, and emerging smart city technologies.…”