{
  "id": "emitters:macro-cell-tower",
  "collection": "emitters",
  "slug": "cell-tower",
  "name": "Macro cell tower (LTE / 5G sector antenna)",
  "summary": "Sector antennas radiate on the order of 1000 W EIRP per sector on the main beam, which is aimed above and away from the tower base — ground-level exposure directly beneath a tower is usually lower than at a few hundred metres away.",
  "status": "verified",
  "lastVerified": "2026-08-12",
  "data": {
    "aliases": [
      "base station",
      "mobile phone mast",
      "cell site",
      "5G tower"
    ],
    "category": "radiofrequency",
    "environment": [
      "outdoor"
    ],
    "bands": [
      {
        "label": "Low band (600–900 MHz)",
        "minHz": 600000000,
        "maxHz": 900000000
      },
      {
        "label": "Mid band (1.7–2.6 GHz)",
        "minHz": 1700000000,
        "maxHz": 2600000000
      },
      {
        "label": "C-band 5G (3.3–4.2 GHz)",
        "minHz": 3300000000,
        "maxHz": 4200000000
      }
    ],
    "transmitPower": {
      "quantity": "power",
      "unit": "W EIRP",
      "value": 1000,
      "basis": "regulatory",
      "note": "Order-of-magnitude figure for a macro sector. Actual EIRP depends on transmitter power, antenna gain and, for 5G massive-MIMO panels, on beamforming that concentrates power toward active users.",
      "sourceIds": [
        "fcc-oet65",
        "arpansa-base-stations"
      ]
    },
    "dutyCycle": "Control channels transmit continuously; traffic channels vary with load. 5G beamforming means the maximum only occurs when a beam is pointed at you.",
    "distanceProfile": [
      {
        "meters": 50,
        "value": {
          "quantity": "power-density",
          "unit": "µW/m²",
          "value": 31800,
          "basis": "computed",
          "method": "S = EIRP / (4πd²) with EIRP = 1000 W, d = 50 m",
          "note": "Main-beam free-space value. At the tower base you are usually far below the main beam, where levels are typically 10–100× lower.",
          "sourceIds": [
            "fcc-oet65"
          ]
        }
      },
      {
        "meters": 100,
        "value": {
          "quantity": "power-density",
          "unit": "µW/m²",
          "value": 7960,
          "basis": "computed",
          "method": "S = EIRP / (4πd²) with EIRP = 1000 W, d = 100 m",
          "note": "Main-beam free-space value.",
          "sourceIds": [
            "fcc-oet65"
          ]
        }
      },
      {
        "meters": 300,
        "value": {
          "quantity": "power-density",
          "unit": "µW/m²",
          "value": 884,
          "basis": "computed",
          "method": "S = EIRP / (4πd²) with EIRP = 1000 W, d = 300 m",
          "note": "Main-beam free-space value.",
          "sourceIds": [
            "fcc-oet65"
          ]
        }
      },
      {
        "meters": 1000,
        "value": {
          "quantity": "power-density",
          "unit": "µW/m²",
          "value": 79.6,
          "basis": "computed",
          "method": "S = EIRP / (4πd²) with EIRP = 1000 W, d = 1000 m",
          "note": "Main-beam free-space value.",
          "sourceIds": [
            "fcc-oet65"
          ]
        }
      }
    ],
    "mitigations": [
      {
        "action": "Establish the actual antenna height, azimuth and downtilt before assuming exposure; look the site up in the FCC ASR database.",
        "effect": "Determines whether a dwelling is in the main beam at all, which changes the estimate by one to two orders of magnitude.",
        "sourceIds": [
          "fcc-asr"
        ]
      },
      {
        "action": "Measure indoors with a directional antenna to identify the dominant azimuth, then use window film or shielding paint on that facade only.",
        "effect": "Targets the one surface that matters instead of shielding a whole room."
      },
      {
        "action": "Compare readings against both the regulatory limit and the Swiss installation limit value to understand where you sit.",
        "effect": "Typical measured residential levels near base stations are hundreds of times below regulatory limits.",
        "sourceIds": [
          "arpansa-base-stations",
          "ch-onir"
        ]
      }
    ],
    "measureWith": [
      "broadband-rf-meter",
      "spectrum-analyser",
      "directional-antenna"
    ],
    "related": [
      "limits:ch-onir-installation-mobile",
      "limits:fcc-mpe-public-300-1500"
    ],
    "questions": [
      "how-far-should-i-live-from-a-cell-tower"
    ]
  },
  "sources": [
    {
      "id": "fcc-oet65",
      "title": "OET Bulletin 65: Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields",
      "publisher": "Federal Communications Commission, Office of Engineering and Technology",
      "url": "https://www.fcc.gov/general/oet-bulletins-line",
      "year": 1997,
      "kind": "government",
      "retrieved": "2026-08-12"
    },
    {
      "id": "arpansa-base-stations",
      "title": "Mobile phone base stations and health",
      "publisher": "Australian Radiation Protection and Nuclear Safety Agency",
      "url": "https://www.arpansa.gov.au/understanding-radiation/radiation-sources/more-radiation-sources/mobile-phone-base-stations",
      "kind": "government",
      "retrieved": "2026-08-12"
    },
    {
      "id": "fcc-asr",
      "title": "Antenna Structure Registration (ASR) public access database downloads",
      "publisher": "Federal Communications Commission",
      "url": "https://www.fcc.gov/wireless/data/public-access-files-database-downloads",
      "kind": "government",
      "retrieved": "2026-08-12"
    },
    {
      "id": "itu-fs-relations",
      "title": "Free-space path loss and power density relations (ITU-R P.525)",
      "publisher": "International Telecommunication Union",
      "url": "https://www.itu.int/rec/R-REC-P.525/en",
      "kind": "standard",
      "retrieved": "2026-08-12"
    }
  ],
  "links": {
    "self": "https://emfbase.com/api/emitters/cell-tower",
    "html": "https://emfbase.com/emitters/cell-tower",
    "markdown": "https://emfbase.com/emitters/cell-tower.md",
    "collection": "https://emfbase.com/api/emitters"
  }
}