![\"Triangulation](\"https://cdn.shopify.com/s/files/1/0672/0299/articles/Triangulation-1024x1024_1024x.jpg?v=1578263710\")
Wifi signal strength can be used as a proxy for distance. Corroborate it with the floor plan image (is the signal going through any walls? Going through ceiling/floor?) and you can triangulate location without a model.
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Wifi signal strength can be used as a proxy for distance. Corroborate it with the floor plan image (is the signal going through any walls? Going through ceiling/floor?) and you can triangulate location without a model.
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Well I think we don't know the position of the wifi spot no ?
", "rawMarkdown": "Well I think we don't know the position of the wifi spot no ?", "votes": null }, { "id": "1215755", "postDate": "02/23/2021 23:06:49", "content": "Training dataset contains XY position given wifi signal strengths so estimating the coordinates of the wifi signal should be possible, like reverse triangulation
", "rawMarkdown": "Training dataset contains XY position given wifi signal strengths so estimating the coordinates of the wifi signal should be possible, like reverse triangulation", "votes": null }, { "id": "1216164", "postDate": "02/24/2021 06:15:05", "content": "I thought of the same solution. But I don't know which parameter is strength.
\nI think the Strength is similar to RSSI.
\nFor example,
\n[1578482907398 TYPE_WIFI 12af0a0f9e5bf7b0bd1a2b3c1a33236e707bd3ce 3fc1c8fa39c6996247670b3a9182b320dc3d9f0a -49 2437 1578482905859]
Is [-49] Strength? Waht is [2437]?
\nI don't know that [-49] is [Tx Power] or [RSSI].
RSSI Usually, [-30dBm~-40dBm] is used.
", "rawMarkdown": "RSSI Usually, [-30dBm~-40dBm] is used.", "votes": null }, { "id": "1216460", "postDate": "02/24/2021 09:20:42", "content": "I thought that a signal would be weaker after going through a wall. So it makes it hard to calculate approximately where a person is in indoor only with three wifi spots.
", "rawMarkdown": "I thought that a signal would be weaker after going through a wall. So it makes it hard to calculate approximately where a person is in indoor only with three wifi spots.", "votes": null }, { "id": "1218175", "postDate": "02/25/2021 16:11:28", "content": "Agreed. I'm using a generally non-ML approach.
\nHowever, some questions arise.
Modeling can help to weight the evidence appropriately.
", "rawMarkdown": "Agreed. I'm using a generally non-ML approach.\nHowever, some questions arise. \n- Should we cater for the accuracy/noise in each signal?\n- How do we impute the signal for the timestamps requested (the wifi signals are taken at different timestamps)? What about the lag time, since not all wifi signals arrive at the same time?\n- What if the different readings don't triangulate to a single, valid location -- they either imply multiple locations (can happen b/c of walls, etc.), inconsistent locations (half imply one location, another half imply a different location), or no valid location?\n- How do we impute the signal strength - distance function for parts of the floor that we don't have an exact waypoint for?\n\nModeling can help to weight the evidence appropriately.", "votes": null }, { "id": "1231599", "postDate": "03/09/2021 05:17:39", "content": "Well I think we don't know the position of the wifi spot no ?
", "votes": null, "replies": [ { "id": 1215755, "author_name": "returnofsputnik", "author_url": "", "post_date": "02/23/2021 23:06:49", "content": "Training dataset contains XY position given wifi signal strengths so estimating the coordinates of the wifi signal should be possible, like reverse triangulation
", "votes": null, "replies": [] } ] }, { "id": 1216164, "author_name": "minakamikichi", "author_url": "", "post_date": "02/24/2021 06:15:05", "content": "I thought of the same solution. But I don't know which parameter is strength.
\nI think the Strength is similar to RSSI.
\nFor example,
\n[1578482907398 TYPE_WIFI 12af0a0f9e5bf7b0bd1a2b3c1a33236e707bd3ce 3fc1c8fa39c6996247670b3a9182b320dc3d9f0a -49 2437 1578482905859]
Is [-49] Strength? Waht is [2437]?
\nI don't know that [-49] is [Tx Power] or [RSSI].
RSSI Usually, [-30dBm~-40dBm] is used.
", "votes": null, "replies": [] }, { "id": 1231599, "author_name": "wangyong101", "author_url": "", "post_date": "03/09/2021 05:17:39", "content": "I thought that a signal would be weaker after going through a wall. So it makes it hard to calculate approximately where a person is in indoor only with three wifi spots.
", "votes": null, "replies": [] }, { "id": 1218175, "author_name": "nigelhenry", "author_url": "", "post_date": "02/25/2021 16:11:28", "content": "Agreed. I'm using a generally non-ML approach.
\nHowever, some questions arise.
Modeling can help to weight the evidence appropriately.
", "votes": null, "replies": [] } ], "raw_markdown_by_id": { "1215737": "Wifi signal strength can be used as a proxy for distance. Corroborate it with the floor plan image (is the signal going through any walls? Going through ceiling/floor?) and you can triangulate location without a model.\n\n", "1215746": "Well I think we don't know the position of the wifi spot no ?", "1215755": "Training dataset contains XY position given wifi signal strengths so estimating the coordinates of the wifi signal should be possible, like reverse triangulation", "1216164": "I thought of the same solution. But I don't know which parameter is strength.\nI think the Strength is similar to RSSI.\nFor example,\n[1578482907398\tTYPE_WIFI\t12af0a0f9e5bf7b0bd1a2b3c1a33236e707bd3ce\t3fc1c8fa39c6996247670b3a9182b320dc3d9f0a\t-49\t2437\t1578482905859]\n\nIs [-49] Strength? Waht is [2437]?\nI don't know that [-49] is [Tx Power] or [RSSI].", "1216200": "RSSI Usually, [-30dBm~-40dBm] is used.", "1216460": "I thought that a signal would be weaker after going through a wall. So it makes it hard to calculate approximately where a person is in indoor only with three wifi spots.", "1218175": "Agreed. I'm using a generally non-ML approach.\nHowever, some questions arise. \n- Should we cater for the accuracy/noise in each signal?\n- How do we impute the signal for the timestamps requested (the wifi signals are taken at different timestamps)? What about the lag time, since not all wifi signals arrive at the same time?\n- What if the different readings don't triangulate to a single, valid location -- they either imply multiple locations (can happen b/c of walls, etc.), inconsistent locations (half imply one location, another half imply a different location), or no valid location?\n- How do we impute the signal strength - distance function for parts of the floor that we don't have an exact waypoint for?\n\nModeling can help to weight the evidence appropriately.", "1231599": "1. Rssi means Received Signal Strength Indicator. the unit is dbm. In some radio project, +/- 10dbm for the possible variable of radio strength change. \n2. the 4 digits after rssi are the wifi freqency band channels（2437, 2422, 5180 and etc ）. There are two freqency band 2.4G(channels could be 2437, 2422 and etc. 11 channels in total ) or 5G(channels could be 5180 and etc. 40 channels in toal). The higher the frequency, the faster the data transmission and shorter the signal range. \nbesides, if crowed environment( more than 10 wifis), the 2.4G wifi may heavily impacted co-channel interference." }, "source": "meta" }