From 363bb89c5e645e319574d0333f91e019155c4db8 Mon Sep 17 00:00:00 2001 From: Jet Hughes Date: Tue, 28 Mar 2023 12:19:38 +1300 Subject: [PATCH] vault backup: 2023-03-28 12:19:38 --- content/notes/09-location-sensors-3.md | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/content/notes/09-location-sensors-3.md b/content/notes/09-location-sensors-3.md index 13dc620c6..8a20ce00c 100644 --- a/content/notes/09-location-sensors-3.md +++ b/content/notes/09-location-sensors-3.md @@ -19,6 +19,8 @@ GPS - Receiver - Buildings reflect and occlude satellite signals - Reducing precision of positioning in urban environments - Makes positioning impossible +> [!INFO] Add a fourth satellite so we can find the clock bias +> there are timer networks where you can get time from an atomic clock (still not accurate but better) Urban Canyon - Urban environment similar to a natural canyon @@ -28,6 +30,9 @@ Urban Canyon - Makes positioning impossible www.hci.otago.ac.nz The end! ![Urban canyon](https://i.imgur.com/WgWREXs.png) ![Urban canyon](https://i.imgur.com/1aKMSLg.png) +> [!INFO] buildings block some satellites +> reflected signals take more time to arrive and disrupt accuracy + GPS - Problems - Urban environment similar to a natural canyon @@ -59,7 +64,6 @@ A(ssisted) GPS ![A(ssisted) GPS](https://i.imgur.com/u7iLeWG.png) - D(ifferential) GPS - Enhancement to GPS to increase location accuracy and integrity - DGPS correct errors using a stationary receiver station with a known location