Modelling, Design, and Implementation of Molecular Communication Systems - Phase 2: Media-Modulation based Molecular Communication

分子通信（MC）通过携带信号粒子的信息交换实现了在基于电磁波传播的传统通信概念失效的环境中的通信。这对于例如微尺度环境和液体介质是真实的。虽然MC是常见的自然通信系统，合成MC系统的设计和实验验证是在一个非常初步的阶段。在这个项目的第一阶段，许多挑战的建模，设计和实验验证的MC系统已得到解决，第一个生物试验台已成功地证明。然而，现有MC设计的一个显著的实际缺点是信号粒子由发射器发射，并且因此必须定期补充以用于连续传输，这即使不是不可能实现也是困难的，特别是在微尺度和医疗应用中。为了克服这个局限性，在这个项目的第二阶段，我们研究了基于媒体调制的MC的新概念。在媒体调制中，发射机通过改变信道中已经存在的信号粒子的属性将其消息嵌入到周围的介质中。在最简单的情况下，信令粒子能够呈现两种不同的状态，并且所传输的信息（例如，比特0或1）由状态表示。为了研究它们的优点和局限性，我们开发了基于媒体调制的MC系统的分析模型。由于介质调制的实用性和性质取决于合适的信号传导粒子的可用性，我们将考虑三种不同的实现选项，即基于磷酸化的MC系统作为基于介质调制的MC的自然示例，官能化聚合物囊泡作为方便的合成选项，以及基于氧化还原的MC系统。基于各自的分析模型，我们将开发相应的调制，检测和估计方案。此外，实验验证所提出的模型和设计概念，我们将开发和实施一个测试平台的聚合物囊泡为基础的MC，其中聚合物囊泡具有光开关绿色荧光蛋白（GFP）的变体固定在其表面作为信号颗粒。该项目的预期成果包括：（1）基于媒体调制的MC系统的通用通信理论建模框架;（2）媒体调制的新型调制、检测和估计方案;（3）全球首个基于聚合物体的MC试验平台;（4）媒体调制的模拟和实验验证以及开发的通信理论模型和系统设计概念。

Molecular communication (MC) enables via the exchange of information carrying signaling particles communication in environments where traditional communication concepts based on the propagation of electromagnetic waves fail. This is true for example for microscale environments and liquid media. Although MC is common in natural communication systems, the design and experimental verification of synthetic MC systems are at a very preliminary stage. In the first phase of this project, many challenges regarding the modelling, design, and experimental verification of MC systems have been tackled and a first biological testbed has been successfully demonstrated. However, one significant practical drawback of existing MC designs is that the signaling particles are emitted by the transmitter and, as a result, have to be regularly replenished for continuous transmission, which is difficult if not impossible to accomplish, especially in microscale and medical applications. To overcome this limitation, in the second phase of this project, we investigate the new concept of media-modulation based MC. In media modulation, the transmitter embeds its message into the surrounding medium by changing the properties of signaling particles that are already present in the channel. In the simplest case, the signaling particles are capable of assuming two different states and the transmitted information (e.g. bit 0 or 1) is represented by the state. To study their benefits and limitations, we develop analytical models for media-modulation based MC systems. Since the practicality and properties of media modulation depend on the availability of suitable signaling particles, we will consider three different realization options, namely phosphorylation-based MC systems as a natural example for media-modulation based MC, functionalized polymersomes as a convenient synthetic option, and redox-based MC systems. Based on the respective analytical models, we will develop corresponding modulation, detection, and estimation schemes. Furthermore, to experimentally verify the proposed models and design concepts, we will develop and implement a testbed for polymersome-based MC, in which polymersomes having photo-switchable green fluorescent protein (GFP) variants immobilized on their surface serve as signaling particles. The expected outcomes of this project include (1) a general communication-theoretical modelling framework for media-modulation based MC systems, (2) novel modulation, detection, and estimation schemes for media modulation, (3) the first polymersome-based MC testbed worldwide, (4) simulative and experimental verification of media modulation as well as the developed communication-theoretical models and system design concepts.