{
  "groups": [
    {
      "id": "concepts",
      "title": "Concepts",
      "title_zh": "概念",
      "sections": [
        {
          "id": "overview",
          "title": "Introduction",
          "title_zh": "导论",
          "summary": "What this documentation covers, how it is organised, and how to read it.",
          "summary_zh": "本套文档的范围、组织方式与阅读方法。",
          "documents": [
            "overview"
          ]
        },
        {
          "id": "foundation",
          "title": "Foundations",
          "title_zh": "基础层",
          "summary": "Units, dimensions, numerical method, and the treatment of error.",
          "summary_zh": "单位与量纲、数值方法以及误差处理。",
          "documents": [
            "units-and-dimensions",
            "numerical-methods"
          ]
        },
        {
          "id": "physics",
          "title": "Physics",
          "title_zh": "物理层",
          "summary": "The physics layer holds two unrelated subjects: the time a measurement is stamped with, and the geometry of the Earth it is measured against.",
          "summary_zh": "物理层包含两个彼此无关的主题：一次测量被标注的时刻，以及它所参照的地球几何。",
          "documents": [],
          "subsections": [
            {
              "id": "physics-time",
              "title": "Time",
              "title_zh": "时间",
              "summary": "Time scales, the leap seconds that keep them aligned with the Earth's rotation, and the calendar that turns an instant into a date.",
              "summary_zh": "时间尺度、使其与地球自转对齐的闰秒，以及把时刻变为日期的日历。",
              "documents": [
                "time-scales",
                "leap-seconds",
                "calendar-and-mjd"
              ]
            },
            {
              "id": "physics-frames",
              "title": "Frames and the Earth",
              "title_zh": "参考系与地球",
              "summary": "The frames a position is measured in, the angle that ties them together, and the ellipsoid that defines the surface.",
              "summary_zh": "测量位置所用的参考系、把各参考系联系起来的角度，以及定义地表的椭球。",
              "documents": [
                "reference-frames",
                "earth-rotation-angle",
                "geodesy-wgs84"
              ]
            }
          ]
        },
        {
          "id": "orbit",
          "title": "Orbit",
          "title_zh": "轨道层",
          "summary": "Orbital elements, element formats, perturbation sources, propagation models, and orbit maintenance.",
          "summary_zh": "轨道根数、元素格式、摄动来源、传播模型与轨道保持。",
          "documents": [
            "keplerian-elements",
            "tle-format",
            "sgp4",
            "perturbations",
            "higher-order-gravity",
            "solar-radiation-pressure",
            "atmospheric-drag",
            "maneuvers",
            "propagator-comparison",
            "ephemeris-interpolation"
          ]
        },
        {
          "id": "rf",
          "title": "Radio and propagation",
          "title_zh": "射频与传播",
          "summary": "Doppler shift, link budgets, the propagation medium, and interference.",
          "summary_zh": "多普勒频移、链路预算、传播介质与干扰。",
          "documents": [
            "doppler-and-rate",
            "atmospheric-propagation",
            "link-budget",
            "interference"
          ]
        },
        {
          "id": "network",
          "title": "Constellation and network",
          "title_zh": "星座与网络",
          "summary": "Constellations, coverage, visibility, access, and the behaviour of a network of satellites.",
          "summary_zh": "星座、覆盖、可见性、接入以及卫星网络的行为。",
          "documents": [
            "constellations",
            "access-and-availability",
            "handover-and-routing"
          ]
        },
        {
          "id": "ops",
          "title": "Operations",
          "title_zh": "运行层",
          "summary": "Command, tracking and telemetry, and the planning of daily operations.",
          "summary_zh": "测控链路以及日常运行的规划。",
          "documents": [
            "tt-and-c",
            "operations-planning"
          ]
        },
        {
          "id": "sim",
          "title": "Simulation",
          "title_zh": "仿真层",
          "summary": "Scenarios, events, and the reasoning behind a simulation result.",
          "summary_zh": "场景、事件以及仿真结果的解读。",
          "documents": [
            "scenario-simulation"
          ]
        }
      ]
    },
    {
      "id": "implementation",
      "title": "Implementation",
      "title_zh": "实现",
      "sections": [
        {
          "id": "workspace",
          "title": "The ApsisRS workspace",
          "title_zh": "ApsisRS 工作区",
          "summary": "How the library is organised, and the provenance of what it implements.",
          "summary_zh": "该库的组织方式，以及其所实现内容的来源。",
          "documents": [
            "architecture-apsis-rs",
            "standards-and-provenance"
          ]
        }
      ]
    }
  ]
}