Hi,
Purpose: To design a high accuracy GPS tracker.
Experiment: To test accuracy of Sparkfun NeoM9N chip antenna https://www.sparkfun.com/products/15733
Setup: Connected Sparkfun SAMD21 Micro https://www.sparkfun.com/products/15423 with NeoM9N module
Code: https://github.com/sparkfun/SparkFun_u- … sition.ino
Test environment: Terrace open to sky. Setup is kept stationary at one point. Over 100 readings are recorded at this point
Inference: To confirm if the distance between the readings is approx 1.5m as mentioned in the features of NeoM9N. I have calculated distance between the readings considering the 1st reading as reference using haversine formula.
Result: No two readings are same. The last 4 digits of both lat and long keep varying. The minimum distance is 0.03m and the maximum distance is 11.5m.
Please find the readings as below:
(For the sake of privacy I have morphed the 2 digits before the decimal point.)
0.5251363 0.7775893
0.5251364 0.777584
0.5251361 0.7775896
0.5251362 0.7775937
0.5251365 0.7775906
0.5251376 0.7775885
0.5251386 0.7775892
0.5251395 0.7775893
0.5251407 0.7775922
0.5251432 0.777579
0.5251458 0.777559
0.5251486 0.7775451
0.52515 0.7775396
0.5251517 0.7775366
0.5251548 0.7775324
0.5251579 0.7775287
0.5251602 0.7775256
0.5251628 0.7775226
0.5251653 0.7775199
0.5251675 0.7775178
0.5251698 0.7775163
0.5251721 0.7775152
0.5251739 0.7775146
0.5251763 0.7775138
0.5251793 0.777513
0.5251812 0.777512
0.5251831 0.7775111
0.5251855 0.7775098
0.5251872 0.7775092
0.5251887 0.7775091
0.5251904 0.7775088
0.525192 0.7775086
0.5251937 0.7775083
0.5251948 0.7775078
0.5251957 0.7775072
0.5251967 0.7775073
0.5251974 0.777507
0.5251983 0.7775064
0.5251992 0.7775055
0.5251995 0.7775049
0.5251994 0.7775044
0.5251995 0.7775039
0.5251996 0.7775034
0.5251998 0.7775034
0.5252002 0.7775035
0.5252003 0.7775037
0.5252003 0.777504
0.5252001 0.7775047
0.5252001 0.7775055
0.5252001 0.7775062
0.5252003 0.7775065
0.5252 0.7775072
0.5252001 0.7775077
0.5252003 0.7775082
0.5252005 0.7775086
0.5252009 0.7775087
0.5252009 0.7775095
0.5252006 0.7775104
0.5252005 0.777511
0.5252005 0.7775117
0.5252001 0.7775125
0.5251996 0.7775134
0.5251994 0.7775141
0.5251985 0.7775153
0.5251976 0.7775157
0.5251968 0.7775161
0.5251965 0.7775159
0.5251963 0.7775158
0.525196 0.7775157
0.5251957 0.7775157
0.5251939 0.7775163
0.5251925 0.7775167
0.5251911 0.7775172
0.5251894 0.7775181
0.5251882 0.7775187
0.5251865 0.7775197
0.5251853 0.7775202
0.525184 0.7775207
0.5251833 0.7775211
0.5251822 0.7775215
0.525181 0.7775219
0.52518 0.7775225
0.525179 0.7775228
0.5251781 0.777523
0.5251772 0.7775232
0.525176 0.7775234
0.5251747 0.7775238
0.525174 0.7775242
0.525173 0.7775249
0.5251724 0.7775252
0.5251718 0.7775254
0.5251711 0.7775253
0.5251703 0.7775255
0.5251695 0.7775257
0.525169 0.7775261
0.5251688 0.7775264
0.5251685 0.7775262
0.525168 0.7775261
0.5251675 0.7775264
0.525167 0.7775267
0.5251669 0.7775268
0.5251664 0.7775273
0.525166 0.7775274
0.5251655 0.7775275
0.5251649 0.7775279
0.5251645 0.7775283
0.525164 0.777529
0.5251635 0.7775295
0.5251632 0.7775297
0.5251628 0.7775299
0.5251622 0.77753
0.5251616 0.7775306
0.5251613 0.7775308
0.5251609 0.7775309
0.5251607 0.777531
0.5251604 0.7775314
0.5251599 0.777532
0.5251593 0.7775326
0.5251589 0.7775332
0.5251589 0.777534
0.5251589 0.7775349
0.5251587 0.7775357
0.525158 0.7775369
0.5251576 0.7775384
0.5251571 0.7775395
0.5251565 0.7775402
0.525156 0.7775411
0.5251553 0.7775422
0.5251547 0.7775431
0.5251541 0.7775437
0.5251533 0.7775445
0.5251523 0.7775452
0.5251517 0.7775454
0.5251508 0.7775459
0.52515 0.7775461
0.5251496 0.7775464
0.5251492 0.7775469
0.5251488 0.7775473
0.5251484 0.7775475
0.5251479 0.7775477
0.5251475 0.777548
0.5251471 0.7775484
0.5251468 0.7775489
0.5251468 0.7775493
0.5251466 0.7775496
0.5251464 0.7775497
0.5251462 0.7775501
0.5251459 0.7775505
0.5251457 0.7775509
0.5251454 0.7775516
0.5251449 0.777552
0.5251443 0.7775523
0.5251439 0.7775525
0.5251433 0.7775529
0.5251429 0.7775528
0.5251423 0.7775529
0.5251415 0.7775528
0.5251408 0.7775527
0.5251399 0.777553
0.5251395 0.777553
0.5251388 0.7775533
0.5251388 0.7775526
0.5251381 0.7775523
0.5251374 0.7775521
Please help.
Is my experiment correct? I fail to understand how can the module give readings 11m apart for stationary point.
Thanks!