Scheduling Within a Demand Access Paradigm for NASA's Deep Space Network

NASA’s Deep Space Network (DSN) is the primary resource for communications and navigation for inter- planetary space missions, for both NASA and partner agencies. As part of an investigation into improved effi- ciency and responsiveness, we have been exploring and prototyping the infusion of a ”demand access” model into the DSN scheduling process. Today, DSN is fully pre-scheduled in advance, and many users rely on a stable schedule to plan their own spacecraft activities, weeks in advance of execution. However, a new class of missions is emerging that may not be scheduled as far in advance, and may be event-driven in coming across sci- ence targets at unpredictable times. These users could take advantage of an on-demand mechanism to down- load data. In this paper, we describe a prototype of the demand access process which consists of reserving blocks of shared antenna time (demand access tracks) and utilizing special ”beacon” tracks to request access to those blocks. Furthermore, we dive into a proposed scheduling solution for the beacon tracks using an ag- gregated value function in order to minimize data la- tency and track starvation.

美国国家航空航天局（NASA）的深空网络（Deep Space Network，DSN）是支持NASA及合作机构开展星际航天任务通信与导航的核心资源。为提升运行效率与响应能力，我们正探索并构建原型方案，将"按需接入（demand access）"模式融入DSN的调度流程。当前，DSN的调度完全采用提前预排模式，众多用户需依赖稳定的调度安排，在任务执行前数周规划自身航天器的作业活动。然而，一类新型任务正逐步涌现，这类任务无法提前太久规划排期，且可能在偶遇科学目标时因时机不可预测而触发，属于事件驱动型任务，此类用户可借助按需接入机制下载数据。在本文中，我们将介绍一款按需接入流程的原型系统，该系统包含预留共享天线时段块（demand access tracks，按需接入轨道），并通过特殊的"信标"轨道申请使用这些预留时段。此外，我们还深入探讨了一种针对信标轨道的调度解决方案，该方案采用聚合价值函数，以最小化数据延迟与轨道饥饿问题。

搜集汇总

背景与挑战

背景概述

该数据集聚焦于NASA深空网络（DSN）的调度优化，针对新兴任务对按需访问的需求。它介绍了按需访问原型，包括需求访问轨道和信标轨道的使用，并提出了基于聚合价值函数的调度解决方案，以降低数据延迟和避免轨道饥饿。