Target RF-Performance is not optimal

[orgua]

Testbed should be a ring-network, but there are still two gaps.

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

[orgua]

Switched Antenna of Node 9 & 10 (just initial test):

• +15-16 dB improvement with 2x new antenna
• +6-13 dB for just one new Antenna

          8     9    10    11    12
     +-----------------------------
   8 |        -79   -83            
   9 |  -84         -68   -88      
  10 |  -87   -66         -79   -91
  11 |        -84   -78         -77
  12 |              -87   -75      

New Antennas now on Node 8 & 12 (in Hope to close the Gaps):

          8     9    10    11    12
     +-----------------------------
   8 |        -76                  
   9 |  -73         -76   -87      
  10 |        -77         -78      
  11 |        -89   -79         -59
  12 |                    -63      

Additional new Ant on Node 1 & 7:

• still no link between 1 & 12
  • also raised node 12 on top of white board
• uni-dir link between 8 & 7

          8     9    10    11    12     1     2     3     4     5     6     7
     +-----------------------------------------------------------------------
   8 |        -71   -82                                                   -90
   9 |  -69         -82   -89                                                
  10 |  -81   -82         -81   -85                                          
  11 |              -81         -67                                          
  12 |              -89   -70                                                
   1 |                                      -71                              
   2 |                                -68         -77   -87                  
   3 |                                      -77         -69   -91            
   4 |                                      -86   -69         -78            
   5 |                                                  -80         -71      
   6 |                                                        -71         -87
   7 |                                                              -89      

Baseline from first Post:

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

[orgua]

Current Baseline

          8     9    10    11    12
     +-----------------------------
   8 |        -69                  
   9 |  -65         -74   -84      
  10 |        -74         -80   -82
  11 |        -85   -81         -68
  12 |              -86   -71      

Node 9 & 10 - replace chip-ant with 5/8-whip

• 1/4 antennas on both sides gave + 6-15 dB
• 5/8 antenna

Rx\Tx     8     9    11    12
     +-----------------------
   8 |        -79            
   9 |  -80                  
  11 |        -88         -68
  12 |              -71      

Shorten to 1/4-whip

Tx⟍Rx     8     9    10    11    12
     +-----------------------------
   8 |        -79         -91      
   9 |  -79         -76   -85      
  10 |        -73                  
  11 |        -83               -68
  12 |                    -71      

Going back to Baseline ChipAntenna

Tx⟍Rx     8     9    10    11    12
     +-----------------------------
   8 |        -70   -90   -89      
   9 |  -67         -77   -87      
  10 |        -77               -87
  11 |  -87   -88               -68
  12 |                    -71      

[orgua]

Add two Nodes

• trying to close one Gap to get U-shaped network
• Node 13 in II64C - behind copy-machine
• Node 14 in II64B - on microwave
• node 14 does transmit, but is not received by others ?!?

Tx⟍Rx     1     2     3     4     5     6     7     8     9    10    11    12    13    14
     +-----------------------------------------------------------------------------------
   1 |        -70                                                                        
   2 |  -67         -76                                                                  
   3 |        -75         -68   -90                                                      
   4 |              -67         -80                                                      
   5 |              -87   -81         -71                                                
   6 |                          -71         -81                                 -86      
   7 |                                -83                                       -82      
   8 |                                                  -70   -90               -89      
   9 |                                            -67         -77   -87                  
  10 |                                                  -77         -81   -87            
  11 |                                                        -83         -61            
  12 |                                                              -65                  
  13 |                                -87   -81   -88                                 -82
  14 |                                                                                   

replaced Target 14

• node 14 has now target of node 12
• node 12 is now in II70
• node 8 is now much closer at door (still on cable-channel, west wall)

Tx⟍Rx     1     2     3     4     5     6     7     8     9    10    11    12    13    14
     +-----------------------------------------------------------------------------------
   1 |        -71                                                                        
   2 |  -68         -75                                                                  
   3 |        -75         -68                                                            
   4 |        -90   -67         -81                                                      
   5 |                    -82         -71                                                
   6 |                          -71         -80                                 -85      
   7 |                                -83         -82                           -77      
   8 |                                      -80         -74         -86   -85         -72
   9 |                                            -71         -79   -86   -75            
  10 |                                                  -78         -88   -83            
  11 |                                            -85   -88   -89                        
  12 |                                            -82   -75   -84                        
  13 |                                -87   -76                                       -61
  14 |                                                                                   

move Node 14

• Node 14 in cup-Board, kitchen II64B
• also deleted & regenerated all tasks and firmwares (fixed rx of node14-packets)

Tx⟍Rx     1     2     3     4     5     6     7     8     9    10    11    12    13    14
     +-----------------------------------------------------------------------------------
   1 |        -70         -92                                                            
   2 |  -67         -76   -91                                                            
   3 |        -76         -68   -86                                                      
   4 |  -88   -90   -67         -78                                                      
   5 |              -87   -80         -71                                                
   6 |                          -71         -81                                 -87      
   7 |                                -84         -82                           -77      
   8 |                                      -80         -83         -86   -84         -90
   9 |                                            -80         -80   -88   -78            
  10 |                                                  -79         -87   -84            
  11 |                                            -85         -89                        
  12 |                                            -82   -77   -84                        
  13 |                                -88   -76                                       -62
  14 |                                                                          -63      

Updated Floorplan (WIP)

• only temporary, for some hours
• node 13 & 14 are in II70 otherwise

[orgua]

RUN A

Changes to above picture / last comment:

• Node 12 in II71, right wall, mid room
• Node 13 in II64C, top right corner
• Node 14 in II64B, top right corner

Tx⟍Rx     1     2     3     4     5     6     7     8     9    10    11    12    13    14
     +-----------------------------------------------------------------------------------
   1 |        -71   -84   -91                                                            
   2 |  -68         -77                                                                  
   3 |  -80   -77         -70   -89                                                      
   4 |  -87         -69         -81                                                      
   5 |              -90   -82         -72                                                
   6 |                          -73         -80                                          
   7 |                                -82         -82                                    
   8 |                                      -81         -80         -87   -80   -89   -88
   9 |                                            -77         -78   -88   -78            
  10 |                                                  -78         -87   -68            
  11 |                                            -85         -85         -80            
  12 |                                            -81   -82   -72   -82                  
  13 |                                                                                -63
  14 |                                            -85                           -60      

Goal:

• connection between 14 <--> 7 AND 13 <--> 6 or 5

RUN B

Changes:

• Node 12 in II69, right wall, mid room
• Node 13 in top left Corner of II64C
• Node 14 more to the right corner of II64B

Tx⟍Rx     1     2     3     4     5     6     7     8     9    10    11    12    13    14
     +-----------------------------------------------------------------------------------
   1 |        -71   -84   -91                                                            
   2 |  -68         -79                                                                  
   3 |  -82   -79         -71   -87                                                      
   4 |  -86         -69         -80                                                      
   5 |              -87   -81         -72                                                
   6 |                          -72         -80                                 -78      
   7 |                                -83         -83                           -87      
   8 |                                      -81         -80         -87   -60   -83   -89
   9 |                                            -77         -81   -89   -56            
  10 |                                                  -81         -90   -80            
  11 |                                            -85                     -81            
  12 |                                            -61   -61   -84   -83                  
  13 |                                -81   -87   -84                                 -68
  14 |                                            -87                           -64      

RUN C

Changes:

• Node 9 -> Cage on Emu & Hrv

Tx⟍Rx     1     2     3     4     5     6     7     8     9    10    11    12    13    14
     +-----------------------------------------------------------------------------------
   1 |        -71   -85   -91                                                            
   2 |  -68         -77                                                                  
   3 |  -82   -77         -70   -85                                                      
   4 |  -87         -69         -80                                                      
   5 |              -86   -81         -72                                                
   6 |                          -72         -80                                 -80      
   7 |                                -83         -83                           -85      
   8 |                                      -81         -85         -86   -60   -80   -82
   9 |                                            -82         -80   -87   -56            
  10 |                                            -88   -79         -89   -80            
  11 |                                            -85                     -81            
  12 |                                            -61   -61   -85   -84                  
  13 |                                -82   -84   -80                                 -63
  14 |                                            -81                           -60      

RUN D

Change:

• Node 9 - UART of Beaglebone destroyed

Tx⟍Rx     1     2     3     4     5     6     7     8    10    11    12    13    14
     +-----------------------------------------------------------------------------
   1 |        -70   -84   -90                                                      
   2 |  -67         -77                                                            
   3 |  -81   -78         -70   -86                                                
   4 |  -86         -69         -80                                                
   5 |              -87   -81         -72                                          
   6 |                          -72         -80                           -81      
   7 |                                -83         -83                     -89      
   8 |                                      -81               -86   -60   -80   -81
  10 |                                                              -81            
  11 |                                            -85               -82            
  12 |                                            -61   -86   -85                  
  13 |                                -83   -88   -81                           -63
  14 |                                            -79                     -61      

Updated Floorplan (2023-11-17)

[orgua]

Update:

• testbed-structure was updated (mostly uses lower office-row)
• new v1.2 targets with external antenna were designed and wait for production