Adaptive Millimetre-wave Integrated TranSmitters

毫米波可实现超高数据速率。然而，高传播损耗限制了覆盖范围。以大的直流功率为代价，覆盖范围和数据速率可以通过使用具有大量有源路径的天线发射器来大规模地增加。在ADAMIS中，我们希望探索毫米波系统的新架构和方法，通过在系统、电路和器件级应用自适应性，实现数据速率、传输距离和直流功耗的最佳权衡。为此，开发了一种自适应发射机前端，其具有多个可切换和可调谐的有源路径。在高达几厘米的非常低的覆盖范围（例如，对于机载通信）和/或低数据速率下，仅激活具有低方向性的一个有源天线路径。电路在低功率模式下操作，并且矢量调制器被去激活。对于长距离（最高10 m）和/或大数据速率（最高50 Gb/s），所有有源天线路径包括激活用于波束成形的矢量调制器。在这种模式下，电路以最大增益和输出功率工作。在毫米波频率下，矢量调制器内所需的可变增益放大器强烈地改变其相位与增益，这需要复杂的控制。我们将研究解决这个问题的高级拓扑结构，例如通过具有逆误差的级联级。为了更好地理解和优化电路，我们推导出相关传递函数的解析表达式。对于参数（路径数，功率和矢量）的调整，我们研究和比较两种方法：第一，通过扫描参数在毫米波频率和测量接收强度或误码率，第二，通过采用低功率2/5 GHz的雷达定位的发射机和接收机。因此，最佳传输角度和距离可以被可靠地提取到大的距离。最新的IHP BiCMOS技术用于开发工作在220-270 GHz的前端。每条路径由天线、功率放大器、矢量调制器、混频器、四倍频器和二进制相位调制器组成。几个天线结构和封装的概念将进行调查。为了测试开发的发射机前端，将设计一个使用现有实验室设备的接收机。为了最大限度地降低功耗，并允许在本项目的有限资源内实现完全集成的发射机，我们将重点关注BPSK（二进制相移键控）调制，通过利用差分电路相位，可以实现几乎可以忽略不计的直流功耗。因此，不需要功耗数据转换器。由于高达50 GHz的大可用带宽，50 Gb/s的高数据速率是可能的。在低数据速率和/或低距离模式下，超低直流功耗是可能的。

Millimetre-waves enable ultra-high data rates. However, the high propagation loss limits the coverage range. At the expense of a large dc power, the coverage range and the data rate can be massively increased by using antenna transmitters featuring a large number of active paths. In ADAMIS we want to explore novel architectures and methodologies for millimetre-wave systems allowing an optimum trade-off regarding data rate, transmission distance and dc power consumption by applying adaptivity at system, circuit and device level. For this purpose, an adaptive transmitter frontend is developed, which features multiple switchable and tuneable active paths. At very low coverage range up to a few centimetres (e.g. for on-board communication) and/or low data rates, only one active antenna path with low directivity is activated. The circuits operate in a low power mode and the vector modulators are deactivated. For large distances (up to 10 m) and/or large data rates (up to 50 Gb/s) all active antenna paths incl. vector modulators for beamforming are activated. In this mode, the circuits operate at maximum gain and output power. At millimetre-wave frequencies, the variable gain amplifiers required within the vector modulators strongly change their phase versus gain requiring a complex control. We will investigate advanced topologies solving this problem, e.g. by cascading stages with inverse errors. To better understand and optimise the circuits we derive analytical expressions for the relevant transfer functions. For the adjustment of the parameters (number of paths, power and vectors), we study and compare two approaches: First, by scanning the parameters at millimetre-wave frequencies and measuring the receive strength or bit error rate, and second, by employing a low-power 2/5 GHz radar for positioning of the transmitter and the receiver. Hence, the optimum transmission angles and distances can be reliably extracted up to large distances. The latest IHP BiCMOS technology is used for the development of the frontend operating at 220-270 GHz. Each path consists of an antenna, a power amplifier, a vector modulator, a mixer, a frequency quadrupler and a binary phase modulator. Several antenna structures and packaging concepts will be investigated. To test the developed transmitter frontend, a receiver using existing lab-equipment will be designed. To minimize the power consumption and to allow the realisation of a fully integrated transmitter within the limited resources of this project we will focus on BPSK (binary phase shift keying) modulation, which can be realised with almost negligible dc power consumption by exploiting the differential circuit phases. Hence, no power consuming data converters are required. Due to the large available bandwidth of up to 50 GHz, a high data rate of 50 Gb/s is possible. In the low data rate and/or low distance mode, ultra-low dc power consumption is possible.