Filtering Stations by Signal

Filter reference stations by the GNSS signals they support.

How Signal Filters Work

A SignalFilter has two fields:

• signals - at least one must match (OR)
• and - chain filters that must all match (AND)

Example: GPS Band Signals

This guide uses GPS as an example. Other constellations (GLONASS, Galileo, BeiDou, QZSS) are also supported. See SignalType for the full list.

Band	Signals
L1	GPS_L1_CA, GPS_L1C, GPS_L1P
L2	GPS_L2_CA, GPS_L2C, GPS_L2P
L5	GPS_L5

Find Stations with L1

{
  stations(limit: 5, filter: {
    signals: [{
      signals: [GPS_L1_CA, GPS_L1C, GPS_L1P]
    }]
  }) {
    content { uuid name }
  }
}

curl -X POST https://graphql.pointonenav.com/graphql \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $APITOKEN" \
  -d '{"query": "{ stations(limit: 5, filter: { signals: [{ signals: [GPS_L1_CA, GPS_L1C, GPS_L1P] }] }) { content { uuid name } } }"}'

Find Stations with L1 AND L2

{
  stations(limit: 5, filter: {
    signals: [{
      signals: [GPS_L1_CA, GPS_L1C, GPS_L1P],
      and: [
        { signals: [GPS_L2_CA, GPS_L2C, GPS_L2P] }
      ]
    }]
  }) {
    content { uuid name }
  }
}

curl -X POST https://graphql.pointonenav.com/graphql \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $APITOKEN" \
  -d '{"query": "{ stations(limit: 5, filter: { signals: [{ signals: [GPS_L1_CA, GPS_L1C, GPS_L1P], and: [{ signals: [GPS_L2_CA, GPS_L2C, GPS_L2P] }] }] }) { content { uuid name } } }"}'

Find Stations with L1, L2, AND L5

{
  stations(limit: 5, filter: {
    signals: [{
      signals: [GPS_L1_CA, GPS_L1C, GPS_L1P],
      and: [
        { signals: [GPS_L2_CA, GPS_L2C, GPS_L2P] },
        { signals: [GPS_L5] }
      ]
    }]
  }) {
    content { uuid name }
  }
}

curl -X POST https://graphql.pointonenav.com/graphql \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $APITOKEN" \
  -d '{"query": "{ stations(limit: 5, filter: { signals: [{ signals: [GPS_L1_CA, GPS_L1C, GPS_L1P], and: [{ signals: [GPS_L2_CA, GPS_L2C, GPS_L2P] }, { signals: [GPS_L5] }] }] }) { content { uuid name } } }"}'

Combine with Location

Find triple-band stations within 150km of San Francisco:

{
  stations(filter: {
    point: {
      position: { lat: 37.7749, lon: -122.4194 },
      radiusMeters: 150000
    },
    signals: [{
      signals: [GPS_L1_CA, GPS_L1C, GPS_L1P],
      and: [
        { signals: [GPS_L2_CA, GPS_L2C, GPS_L2P] },
        { signals: [GPS_L5] }
      ]
    }]
  }) {
    content { uuid name }
  }
}

curl -X POST https://graphql.pointonenav.com/graphql \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $APITOKEN" \
  -d '{"query": "{ stations(filter: { point: { position: { lat: 37.7749, lon: -122.4194 }, radiusMeters: 150000 }, signals: [{ signals: [GPS_L1_CA, GPS_L1C, GPS_L1P], and: [{ signals: [GPS_L2_CA, GPS_L2C, GPS_L2P] }, { signals: [GPS_L5] }] }] }) { content { uuid name } } }"}'

Filter Logic

Pattern	Meaning
signals: [A, B]	A OR B
and: [{ signals: [A] }, { signals: [B] }]	A AND B