The advent of satellite-borne machine learning hardware accelerators has
enabled the on-board processing of payload data using machine learning
techniques such as convolutional neural networks (CNN). A notable example is
using a CNN to detect the presence of clouds in hyperspectral data captured on
Earth observation (EO) missions, whereby only clear sky data is downlinked to
conserve bandwidth. However, prior to deployment, new missions that employ new
sensors will not have enough representative datasets to train a CNN model,
while a model trained solely on data from previous missions will underperform
when deployed to process the data on the new missions. This underperformance
stems from the domain gap, i.e., differences in the underlying distributions of
the data generated by the different sensors in previous and future missions. In
this paper, we address the domain gap problem in the context of on-board
hyperspectral cloud detection. Our main contributions lie in formulating new
domain adaptation tasks that are motivated by a concrete EO mission, developing
a novel algorithm for bandwidth-efficient supervised domain adaptation, and
demonstrating test-time adaptation algorithms on space deployable neural
network accelerators. Our contributions enable minimal data transmission to be
invoked (e.g., only 1% of the weights in ResNet50) to achieve domain
adaptation, thereby allowing more sophisticated CNN models to be deployed and
updated on satellites without being hampered by domain gap and bandwidth
limitations.

利用卫星搭载的机器学习硬件加速器，通过卷积神经网络等机器学习技术在机载上处理有效载荷数据的出现，其中一个重要的例子是使用卷积神经网络在地球观测任务中检测高光谱数据中云的存在，仅将晴空数据进行下行传输以节省带宽。然而，在新任务部署之前，使用新传感器的新任务将没有足够的代表性数据集来训练卷积神经网络模型，而仅使用以前任务的数据训练的模型在新任务的数据处理过程中会表现不佳。这个问题源于领域差异，即由以前和未来任务中由不同传感器生成的数据的基本分布的差异。本文针对机载高光谱云检测中的领域差异问题进行了研究。我们的主要贡献在于制定了由具体的地球观测任务驱动的新领域适应任务，开发了一种新颖的用于带宽高效、有监督领域适应的算法，并在太空部署型神经网络加速器上验证了测试时领域适应算法。我们的贡献使得只需最小程度的数据传输（例如，ResNet50 中只传输 1% 的权重）即可实现领域适应，在卫星上部署和更新更复杂的卷积神经网络模型，而不会受到领域差异和带宽限制的阻碍。