*Triangulation*refers to the process of determining the location of a point by forming triangles to it from known points, using only angle measurements.*Trilateration*(*True Range Multilateration)*is a method of determining the location of a point using multiple known distance measurements from known points.*Triangulateration*involves the use of both angle and distance measurements to determine the location of a point.- Apply the following techniques to find the location of unknown points using only a Garmin GPSr and a creative interpretation of the above methods.

**1.1. Find the point of intersection between two bearings from two points**

1.1.1. Find the coordinates for a distant landmark within visual range

Landmark (X) in visual range |
Save current location as Waypoint (B) |
Project a waypoint beyondLandmark (X) |
Save Waypoint (A) |

Move to a new location and save Waypoint (C) |
Project a waypoint beyondLandmark (X) |
Save Waypoint (D) |
Create new route on GPSr... |

...from Waypoint (A) to (B)... |
...add Waypoint (B) to (C)... |
...finish Waypoint (C) to (D) |
Mark Waypoint (X) atroute intersection |

**1.1.2. Find the coordinates for an unknown waypoint where two
locations and bearings are known**

Move to first location and save as Waypoint (B) |
Project a waypoint atspecified Bearing |
Save Waypoint (A) |
Move to second location... |

Save second location as waypoint (C) |
Project a waypoint atspecified Bearing |
Save Waypoint (D) |
Create new route on GPSr... |

...from Waypoint (A) to (B)... |
...add Waypoint (B) to (C)... |
...finish Waypoint (C) to (D) |
Mark Waypoint (X) atroute intersection |

**1.2. Find the point of intersection between two
bearings to two points**

**Modify each bearing between 001° and 180° by adding 180°****Modify each bearing between 181° and 360° by subtracting 180°**

Move to first location and save as Waypoint (B) |
Project a waypoint atspecified Bearing |
Save Waypoint (A) |
Move to second location... |

Save second location as waypoint (C) |
Project a waypoint atspecified Bearing |
Save Waypoint (D) |
Create new route on GPSr... |

...from Waypoint (A) to (B)... |
...add Waypoint (B) to (C)... |
...finish Waypoint (C) to (D) |
Mark Waypoint (X) atroute intersection |

2.1. Find the point of intersection between multiple points with known distances

**Find the coordinates for an unknown waypoint where two locations and distances are known (Bilateration)****Find the coordinates for an unknown waypoint where three locations and distances are known (Trilateration)**

Two known locations, points (A) and (B) |
Create Proximity Alert atspecified distance for point (A) |
Create Proximity Alert atspecified distance for point (B) |
Two solutions exist where Proximity (A)
and (B)
intersect |

Three known locations, points (A), (B) and (C) |
Two solutions
exist where Proximity (A)
and (B)
intersect |
Create Proximity Alert atspecified distance for point (C) |
Mark Waypoint (X) whereProximity (A)(B)(C) intersect |

**3.1. Find the points of intersection on a circle with a line by bearing**

Save 'Circle' location as Waypoint (A) |
Move to 'Bearing' location and save as Waypoint (B) |
Create Proximity Alert atspecified distance for point (A) |
Project a waypoint atspecified Bearing |

Save
Waypoint (C) |
Create new route on GPSr... |
...from Waypoint (B) to
(C) |
Two solutions
exist where(B)(C)
intersects
(A) |

**4.1. Find the midpoint between two known points**

Two known locations, points (A) and (B) |
Create new route on GPSrfrom waypoint (A) to (B) |
Create Proximity Alert (A)
at½ distance of Route (A)(B) |
Create Proximity Alert (B)equal to Proximity Alert (A) |

Adjust both Proximity Alertsin equal increments if
theydo not overlap precisely |
Proximity Alerts (A)
and (B)exhibit correct overlap |
Mark location where Proximity Alerts (A)
and (B)
intersect Route (A)(B) |
Saved Waypoint (X)
is(A)(B)
midpoint |

**
4.2. Find the midpoint between three known points**

Three known locations, points (A), (B) and
(C) |
Create new route on GPSrfrom waypoint (A) to (B)and record route distance |
Create new route on GPSrfrom waypoint (B) to
(C)and record route distance |
Create new route on GPSrfrom waypoint (C) to (A)and record route distance |

Solution will be between longest route (A)(B)
andshortest route (C)(A) |
Create Proximity Alert forany point using a value between (A)(B)
and (C)(A) |
Create Proximity Alerts forremaining points using the same value |
If Proximity Alerts do not all overlap, increase the value and repeat process |

Create a Proximity Alert forany point using new value |
Create Proximity Alerts forremaining points using the same value |
If all Proximity Alerts overlap but do not intersect at same point, reduce value and repeat |
Create a Proximity Alert forany point using new value |

Create Proximity Alerts forremaining points using the same value |
Mark Waypoint
(X)where all Proximity Alerts intersect at same point |
Saved Waypoint (X)
is(A)(B)(C) midpoint |
Create Proximity Alert
(X)using final (A)(B)(C) valueto verify solution |

**5.1. Find coordinates to form an equilateral triangle from two known points**

Two known locations, points (A) and (B) |
Create new route on GPSrfrom waypoint (A) to (B) |
Find total distance for Route (A)(B) |
Create Proximity Alert (A)using distance (A)(B) |

Adjust Proximity Alert (A)distance as required for precise intersection with point (B) |
Create Proximity Alert (B)equal to Proximity Alert (A) |
Mark Waypoints
(X) and
(Y)where Proximity Alerts (A) and (B)
intersect |
(A)(X)(B)
and
(A)(Y)(B)form Equilateral Triangles |