Reducing multi-path GPS signal errors in Strava under covered walkways

When students walk under the covered walkways on the national campus in Palikir I often see geolocation errors in their activity track: 


Those long straight spikes in the activity track are probably due to GPS satellite signal echoes off of buildings. These are called multi-path errors. I wanted to see if I could minimize the errors as well as learn how my phone would handle the complex signal environment on campus.

Strava

I obtained a nice, relatively clean and accurate activity track, no spikes. How does one eliminate spikes in a multi-path environment, or in any environment?

  1. Start in a place with a fairly clear view of the sky. I started at the "A" frame in front of the south faculty building as that gave my phone more sky to work with. The geolocation satellites that Strava uses are in orbit around the Earth up in space, your phone needs to "see" the sky to obtain accurate location information. 
  2. Wait at least 30 seconds after tapping on Record before tapping on Start. This lets the phone locate itself accurately.
  3. Walk with the phone in your hand.
  4. Walk at the side of the sidewalk with the best view of sky, the side away from any building.
  5. Hold the phone on the side of the covered sidewalk with the skyview.
  6. Hold the phone so the face of the phone is towards the open sky. 
  7. Do not put the phone in a pocket.
  8. Do not put the phone in a backpack.
  9. Avoid going inside any buildings. 

When I run my phone is mounted on my arm using an armband. The phone has a clear view of the sky from the top of my arm. 

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