Intrinsically Digital Radios

主题：本质数字无线电PI：Oliver Collins Proposal：ECS-0523324此集成系统提案侧重于构建本质数字无线电。大多数现代无线电在数字信号处理器中执行调制，但仍然需要大量的模拟硬件。由于模拟设备从一开始就很大，并且不会随着VLSI特征尺寸的减少而扩展，因此一直在努力实现直接生成RF波形的信号处理链。这种方法的根本问题是高速多位数模转换器(DAC)的精度有限，以及数字硬件的计算能力有限。这项提议提出了一种彻底的新发射机架构，消除了这两个缺陷。其基本思想是，网格结构中代表调制器的分支可以用二进制串来标记，这些二进制串可以通过滤波器，然后直接辐射。因此，建造高精度、高速转换器的整个问题就消除了。这些二进制串是通过列表解码算法离线生成的，并且整个编码器/调制器/发射器只是一个查找表。建议进一步发展这一想法，并使其适用于接收器和其他应用。更广泛的影响：拟议的研究将产生更广泛的影响，因为建立更高的动态范围、更低的功率发射器和接收器是无线设备继续传播的关键。从军用雷达到结构监控系统，一切都可能受益。此外，列表解码方法将在无线通信之外具有应用。在当今的数字世界中，这种接口对于发送和存储信息都至关重要。个人CD播放机、蜂窝电话、高清晰度电视、计算机调制解调器和深空通信系统都使用模数和数模转换块。此外，该项目还将丰富该系的课程，并帮助培训学生在通信系统和超大规模集成电路电路设计方面的知识。

Topic: Intrinsically Digital RadiosPI: Oliver CollinsProposal: ECS-0523324This integrative systems proposal focuses on building intrinsically digital radios. Most modern radios perform modulation in a DSP, but still require extensive analog hardware. Since analog devices are both big to begin with and will not scale with decreases in VLSI feature sizes, there has been an ongoing effort to realize signal-processing chains that generate the RF waveform directly. The fundamental problems with this approach are the limited accuracy available in high-speed multi-bit digital-to-analog converters (DACs) and the limited computational abilities of digital hardware. This proposal presents a radical new transmitter architecture that eliminates both of these deficiencies. The essential idea is that the branches in the trellis structure representing the modulator can be labeled with binary strings, which can be passed through a filter and then radiated directly. Thus, the entire problem of building high accuracy, high-speed converters is eliminated. These binary strings are generated offline by a list-decoding algorithm and the entire coder/modulator/transmitter is merely a look-up table. It is proposed to develop this idea further and to adapt it to receivers and other applications. Broader Impacts: The proposed research will have substantial broader impact since building higher dynamic range, lower power transmitters and receivers is key to the continued spread of wireless devices. Everything from military radars to structural monitoring systems could benefit. Furthermore, the list decoding approach will have applications beyond wireless communications. This interface is critical in today's digital world both to send and store information. Personal CD players, cellular telephones, high definition TV, computer modems, and deep space communication systems all use analog-to-digital and digital-to-analog conversion blocks. In addition, the project will enrich the department's curriculum and help train students in communication systems and VLSI circuit design.