possible Reasons

chip antenna,
- possibly TDK center edge, ANT162442ST
PAN1780 (nRF-Module) design rules want 15 mm ground on each side & 40 mm downwards
- our PCB is shorter on one side and only going 30 mm downwards (but has header there)
- data sheet of antenna has no such constraints, but uses 50 x 20 mm PCB (Width x height)

Pattern Chip Antenna

Measurements (link-matrix)

run on shepherd testbed
8 dBm P_tx
node ID in picture and table mean same device, unless the note says otherwise

baseline

          1     2     3     4     5     6     7
     +-----------------------------------------
   1 |        -75   -90                        
   2 |  -75         -84   -80                  
   3 |  -91   -84         -69   -80            
   4 |        -80   -69         -78            
   5 |              -80   -79         -70      
   6 |                          -70         -91
   7 |                                -90

change node 1, 8 (orientation 180°, pos)

          1     2     3     4     5     6     7
     +-----------------------------------------
   1 |        -69   -83
   2 |  -70         -83   -81
   3 |  -83   -83         -71   -81
   4 |        -80   -71         -79
   5 |              -82   -80         -71
   6 |                          -71         -90
   7 |                                -89

change node 3, 7 (orientation 180°, pos)

          1     2     3     4     5     6     7
     +-----------------------------------------
   1 |        -69
   2 |  -70               -89
   3 |                    -63   -81
   4 |        -88   -63         -80   -91
   5 |              -82   -81         -71
   6 |                          -71         -90
   7 |                                -88

change node 3, 8 (higher, 20cm, above screens)

          1     2     3     4     5     6     7
     +-----------------------------------------
   1 |        -69   -85
   2 |  -70         -84   -88
   3 |  -85   -84         -70   -87
   4 |        -88   -70         -80   -90
   5 |              -88   -81         -71
   6 |                          -71         -90
   7 |                                -88

change node 1, (+90°)

          1     2     3     4     5     6     7
     +-----------------------------------------
   1 |        -68   -83
   2 |  -68         -85   -88
   3 |  -83   -85         -70   -89
   4 |        -88   -70         -80   -91
   5 |              -89   -80         -71
   6 |                    -92   -72         -90
   7 |                                -89

other part of network

(node 7 & 1 were included, but had no connection)

          8     9    10    11    12
     +-----------------------------
   8 |        -79   -89            
   9 |  -81         -81            
  10 |  -91   -81         -89   -92
  11 |              -90         -80
  12 |              -90   -78

Todo

measure pattern
rotate node7 90deg & put higher
add more ground to the shorter side?
replace with wired antenna, antenna line is 50 Ohms
try placing uFL-socket for adding off-the-shelf antenna
add one more node in room II64C to get at least a U-Shape

Higher Power-Consumption during Sleep

old Target - nRF-Only

with latest deep-sleep firmware
wakes 6 n/s and consumed 4 mA for very short time

nRF-MSP-Target

both MCU have deep-sleep firmware
also tried with spi-fram-firmware for msp430
wake-effect from nRF is visible, but base-line is far off -> 500 uA in sleep?
suspects: msp430 or rtc-IC

eval & verify targets

run trafficbench in lab

target vs nordic-DK with varying distances
receptions rates & link-matrix
find asymmetry
maybe check with VNA

orgua / shepherd-targets Goto Github PK

shepherd-targets's People

Contributors

Watchers

shepherd-targets's Issues

possible Reasons

Pattern Chip Antenna

Measurements (link-matrix)

baseline

change node 1, 8 (orientation 180°, pos)

change node 3, 7 (orientation 180°, pos)

change node 3, 8 (higher, 20cm, above screens)

change node 1, (+90°)

other part of network

Todo

old Target - nRF-Only

nRF-MSP-Target

Recommend Projects

Recommend Topics

Recommend Org