Multicore-Processor Based Software-Defined Communication/Network Platform for Underwater Internet of Things  
[PERSON]  
1 School of Electronics and Information Engineering, South China University of Technology, Guangzhou 510641, China; [EMAIL_ADDRESS] (C.L. ); [EMAIL_ADDRESS] (Q.G. ); [EMAIL_ADDRESS] (H.Y. ); [EMAIL_ADDRESS] (F.J.)1  
[PERSON]  
1 School of Electronics and Information Engineering, South China University of Technology, Guangzhou 510641, China; [EMAIL_ADDRESS] (C.L. ); [EMAIL_ADDRESS] (Q.G. ); [EMAIL_ADDRESS] (H.Y. ); [EMAIL_ADDRESS] (F.J.)1  
[PERSON] and [PERSON]  
1 School of Electronics and Information Engineering, South China University of Technology, Guangzhou 510641, China; [EMAIL_ADDRESS] (C.L. ); [EMAIL_ADDRESS] (Q.G. ); [EMAIL_ADDRESS] (H.Y. ); [EMAIL_ADDRESS] (F.J.)1  
Footnote 1: [[https://github.com/guansheng-guansheng](https://github.com/guansheng-guansheng)]([https://github.com/guansheng-guansheng](https://github.com/guansheng-guansheng))  
reconfigurable underwater acoustic communication platforms mainly focused on the physical layer. These systems are usually composed of a DSP chip (signal processing module) and a FPGA chip (DA/AD module). For example, the reconfigurable modem designed by the Massachusetts Institute of Technology is composed of one motherboard and one daughtercard. It includes four configurable input/output (I/O) channels suitable for multiple-input-multiple-output (MIMO) algorithms and analog anti-aliasing filters implemented by an onboard FPGA and a 300 MHz floating-point DSP with 32 MB SDRAM and 32 MB of flash memory [4]. The daughtercard hosts signal conditioning and amplification stages. The underwater sensor network (UWSN) lab at the University of Connecticut has been actively developing an underwater modem based on MIMO orthogonal frequency-division multiplexing (OFDM). A real-time DSP implementation of both a single-input-single-output (SISO) and a MIMO version of the modem is detailed in [5]. The implementation detailed in [6] demonstrates the real-time capabilities with both a floating-point (TI TMS320 C6713) and a fixed-point (TI TMS320 C6416) DSP, achieving data rates of 3.2 and 6.4 kb/s with a SISO and a \(2\times 2\) MIMO modem. Readers may refer to [2; 3] for more literature about reconfigurable underwater acoustic modems. Due to the increasing interest in underwater acoustic networking, it is a trend to add the networking protocols in reconfigurable underwater acoustic processing platforms. Traditional DSP chips focus on pipeline signal processing problems, which are not suitable for multithread processing. A general MCU processor has been applied to solve this problem. In [7], an ARM 6410 processor with an external underwater acoustic modem is used to implement the underwater acoustic network protocols. [PERSON] et al. [8] applied a General-Software-defined Radio Peripheral (USRP) to implement the whole set of communication networking systems from physical layer to network layer. Another common architecture is ARM + DSP dual-core architecture, where the ARM core manages the networking protocols and the peripheral device and the DSP core takes charge of the underwater communication programs [9]. The main disadvantage of the above methods is the poor compatibility between the software simulation and hardware emulation. For example, in a pure software simulation on a network protocol, NS2 and NS3 are the widely used simulation platforms. However, the program of network protocols based on NS2 and NS3 usually cannot be directly applied in the above hardware verification system, and a secondary development, such as code immigration, is required. The University of Padova proposed a simulation platform called SUNSET [10], based on NS2, which is compatible with the hardware verification system, so that the software code can be directly used in the hardware verification system without modification. However, SUNSET considered only the reconfigurable networking protocols. It is interesting to integrate reconfigurable communication and networking.