Mobile radio network


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1. Mobile radio network

This network is used for communicating between the center and mobile stations. This is a older version. The new one is described in next chapter.

1.1. Principle of communication

                   |          |
                  .| 690FC000 |.
                .  |__________| .
   Center     .                  .      Mobile
 __________ .                     .   __________ 
|          |                       . |          |
| 690F8000 |                        .| 690F1001 |                    from fw 10.x.x.x
|__________|                         |__________|
                                                                     DGe N1
Ne 1Cn ...Center on     FPe 1Mn        ...Mobile on...                   oO
                            1b690FC000 ...address for base selection...  ib690FC000
                            1kFFFFC000 ...mask for base selection...     imFFFFC000
                            1c690F8000 ...address of center...           ic690F8000
                            1p20       ...period of reporting to center..ik20

The mobile network contains a Center and the appropriate number of Bases which cover the territory over which the Mobile stations move. The connection between the Center and the Bases can be either direct or indirect using retranslation by means of routing tables. A Mobile station selects the Base station from which it receives the strongest signal and then communicates via this station. The Center records these messages supplemented with information about which Base station the Mobile is available through.

The Mobile makes a selection from stations which it can hear – only those Bases whose addresses, in the range of mask FPe1k, correspond to address FPe1b. The address of the Center and the period of regular reporting is also defined in the Mobile. If no user communication occurs then the regular message is sent from Mobile to the Center.

Example of regular reporting (monitored by the Base station):

Monitoring: source 005AB4B7|5.
15:20:49.9|690FC000 690F1001|690FC000 690F1001|0F3*30* 71 0*90 1mb690F8000
15:20:49.9|690F1001 690FC000|                 |0F3  RFTX  0 06  ack
15:20:49.9|690F8000 690FC000|690F8000 690FC000|0F6  RFTX  0 90 1bc690F1001
15:20:49.9|690FC000 690F8000|                 |0F6*29~ 94 0*06  ack

The first report, labelled mb at the end, arrives from the Mobile to the Base and carries information that it is determined for the Center with address 690F8000. Acknowledgement of receipt from the Base then follows.

Another report, labelled bc, is sent from the Base to the Center and carries information that Mobile 690F1001 is available to the Center via this Base. Acknowledgement from the Center follows.

1.2. Information stored in the center and in the mobile

It is possible to view the list of currently logged in Mobiles by using the smc menu in the Center. The functionality condition for this menu is the restart CU with disconnected service cable.

Mobile stuff
(a)ddr:00000000h (m)ask:00000000h
(c)enter status
Mobiles at RF:
 (0) (1) (2) (3) (4)

Nr   Addr      Base      Timeout  CnfTim
  1  690F1001  690FC000    0289    0304
== send:1  stored:1  mobiles ==

Meaning of items:

Nr 1

serial number of Mobile

Addr 690F1001

address of Mobile

Base 690FC000

address of Base through which the Mobile is currently available

Timeout 0289

remaining time of validity of record (sec), after each Mobile login it is set to a value CnfTim, after reaching zero the Mobile is removed from the list

CnfTim 0304

initial time of validity of record, according to menu Ne1v

send: 1

number of sent records about listed Mobiles

stored: 1

total number of records stored in the Center


The number of Mobiles registered is limited according to type CU used as Center:

  • MR25, MR25ET, MCM302 – 64 Mobiles

  • MR400, MR300, MR160, MC100, MG100, MR900 – 450 Mobiles

  • SW Walrus – 2000 Mobiles

When the number of Mobiles is high then the smc command displayes only part of them send. From the overall stored list we can select a smaller group using filter (a)ddr and (m)ask according to the addresses of Mobiles.

Using an sm1 query in the Mobile, where 1 is the number of the RF channel in mobile mode, we can find out the current state of the Base address and the strength of the signal received from it:

RF protocol HCSMA (Hruska's Carrier Sense Multiple Access)
mobile info on RF channel 1:
RSSI -73 dBm   base 690FC000  

Calling from the Center to the Mobile then looks as follows:


u S00   690F1001    R01 
31/ 75  690FC000    R01 
29/ 67  690F8000   serd 

 serd   690F8000    R01 
30/ 67  690FC000    R01 
31/ 75  690F1001  u S00 
Monitoring: source 005A7A1F|1.
12:11.204|690FC000 690F1001|690FC000 690F1001|0E9  RFTX   0 90 4mb690F8000
12:11.244|690F1001 690FC000|                 |0E9*31~ 77  0*06  ack
12:11.282|690F8000 690FC000|690F8000 690FC000|0EA*31* 75  0*90 4bc690F1001
12:11.373|690FC000 690F1001|690FC000 690F1001|0EA  RFTX  10 98 2mb690F8000
12:11.419|690F1001 690FC000|                 |0EA*31~ 76  0*06  ack
12:11.485|690F8000 690FC000|690F8000 690FC000|0EB*30* 75 18*98 2bc690F1001
12:11.502|690FC000 690F8000|                 |0EB*18~ 83  0*06  ack
12:11.558|690FC000 690F8000|690FC000 690F8000|001*31* 75 32*9A 2cb690F1001

12:11.576|690F8000 690FC000|                 |001*31~ 99  0*06  ack
12:11.638|690F1001 690FC000|690F1001 690FC000|0EC*31* 75 40*9A 2bm690F8000
12:11.638|690FC000 690F1001|                 |0EC  RFTX   0 07 mack

Monitored in the Mobile using parameter iMFPe pp = rx (p)romisc. lvl:PACKET

1.3. Establishing connection

When searching for a connection to the Center the Mobile sends a cq packet which contains addresses:

  • frm 690FC000 = comparison base for searching for Base

  • toa FFFFC000 = mask for selection of Base

Only those stations whose addresses meet the base and mask condition reply. The Mobile then chooses the station with the strongest signal from them and then uses this as the Base. If over a longer period of operation it picks up a stronger signal from another Base it will then start to use that as its own Base and will send this information to the Center.

Monitoring: source 004A1E27|1.
RF mon   |toa      frm     |dst      src     |lNo!DQ!RSS size|TT N
12:36.000|FFFFC000 690FC000|                 |000  RFTX   0 03  cq 
12:43.000|FFFFC000 690FC000|                 |000  RFTX   0 03  cq 
12:50.000|FFFFC000 690FC000|                 |000  RFTX   0 03  cq 
12:51.000|690FC000 690F1001|690FC000 690F1001|490  RFTX   0 90 1mb690F8000
12:51.040|690F1001 690FC000|                 |490*26~ 69  0*06  ack
13:11.000|690FC000 690F1001|690FC000 690F1001|491  RFTX   0 90 2mb690F8000
13:11.040|690F1001 690FC000|                 |491*31~ 69  0*06  ack

Monitoring captures the fact that after calling cq an ack was captured from a suitable Base and then a message was sent through it to the Center.

Monitored in Mobile with parameter iMFPe pp = rx (p)romisc.lvl:PACKET

1.4. Configuration


As is shown in the initial diagram the function of the Center is defined in menu Ne :

Nid|address |M | u   s | L   N |l w n g H|sTO Err  Cent vTO hTO
(0) 0053B76D     -  S00| -  R00|0 0 0 0 -| 15 SERV  OFF 304  30
(1) 690F8000    S00 S00| -  R01|0 0 0 0 -| 15 SERV  ON  304  30
(2) 00000000    S01 S00| -  R02|0 0 0 0 -| 15 SERV  OFF 304  30
(3) 00000000    S02 S00| -  R03|0 0 0 0 -| 15 SERV  OFF 304  30
(4) 00000000    S03 S00| -  R04|0 0 0 0 -| 15 SERV  OFF 304  30
(C)enter:ON e(x)tended:OFF (v)alidity TO:19*16 s (h)istory TO:30

Meaning of parameters:


function of mobile operation center switched on

e(x)tended: OFF

for development purposes

(v)alidity TO: 19*16s

time over which the Center considers the record of availability of a Mobile through a certain Base as valid

(h)istory TO: 30 (sec)

after this time packets with the same network number, i.e. repeated packets, which could have arrived through another Base, are discarded. If packets from the Mobile are not numbered it is necessary to set zero here thus eliminating this control step.


Bases do not require special settings. Their addresses, however, must comply with the conditions set in the Mobile. They must also have a connection to the Center set up either directly or via retranslation using normal routing methods. The Center may also be classified amongst Bases.


The Mobile function in fw 8.x.x.x and older is defined in menu FPe in the respective radio channel:

RF channels:
    Access            |ACK             |coding |Mobile
 id a     del l num TO|fix var rep P hT|mod typ|base     mask     center   per
(0) NORMAL 16 16  4 10| 600 400  5   30|REP DBL|OFF
(1) NORMAL 16 16  4 10| 600 400  5   30|REP DBL|690FC000 FFFFF000 690F8000 20
(2) NORMAL 16 16  4 10| 600 400  5   30|REP DBL|OFF
(3) NORMAL 16 16  4 10| 600 400  5   30|REP DBL|OFF
(4) NORMAL 16 16  4 10| 600 400  5   30|REP DBL|OFF
 (M)obile mode:ON  (b)ase:690FC000  mas(k):FFFFF000
(c)enter addr:690F8000  (p)eriod:20sec

Meaning of parameters:

(M)obile mode:ON

function of mobile RF channel switched on


comparison address for selection of Bases


only those stations whose address are comparable with (b)ase in the mas(k) range can be used as Bases

(c)enter addr: 690F8000

address of mobile operation Center


interval of regular reports to Center

The mobile parameters in fw 10.x.x.x and later are moved into menu DGe :

Dynamic routing: Globals
validity (t)imeout:120sec
mm (m)obile
mm mob(i)le obsol
mm ro(u)ter
mm (b)ase
Mobile obsolete mode parameters:
(b)ase:690FC000  (m)ask:FFFFC000  (c)entre:690F8000
(k)eep timeout:20sec

Meaning of parameters:


function of mobile RF channel switched on


choice the node running in the mobile mode

mm mob(i)le obsol

next parameters:

mm (b)ase:690FC000

comparison address for selection of Bases

mm (m)ask:FFFFC000

only those stations whose address are comparable with (b)ase in the mas(k) range can be used as Bases

mm (c)entre:690F8000

address of mobile operation Center

mm (k)eep timeout:20sec

interval of regular reports to Center

1.5. Remote acces


The Center-Base-Mobile route cannot be simply included in the table route or to the Path packet which is used to create access from a remote CU to the Mobile. If from a remote CU, e.g. 690A0100, we send a Path packet of the following format:

Path32 editor
( 1) 690A0100 
( 2) 690F8000 
( 3) 690FC000 
( 4) 00000000 
( 5) 690F1001 
( 6) 690F1001 
path  690F1001h>!

we then achieve the target only assuming that we know the current Base and have included it in the Path packet route:

path  690F1001h>

u S02   690A0100    R01 
31/ 63  690F8000    R01 
30/ 65  690FC000    R01 
30/ 64  690F1001   serd 

 serd   690F1001    R01 
30/ 64  690FC000    R01 
31/ 64  690F8000    R01 
30/ 68  690A0100  u S02 
path  690F1001h>

The retranslation packet which came to the Center does not use the principle of mobile route construction. In these cases a configuration with a Network Agent is used creating a so-called tunnel, as is described in a separate article.

1.6. Update from fw 8.x.x.x to 10.x.x.x

Upgrade from fw 8.x.x.x and older to fw 10.x.x.x produce the configuration changes. The menu FPe was cancelled and it’s parameters moved to DGe menu (mobile parameters) and FAe menu (radio channel access). It is recommended upgrade together both main module, e.g. E and base module e.g. B

If the upgrade reason is removing the back-up battery problem (see Comment from 1.7.2008) and the configuration changes in the network are difficult, it is possible proceed in this way:

Use the combination of main module serie 8, e.g. E and base module al least B, e.g. B Main module of the serie 8 saves the original configuration in FPe menu and base module B together with configuration backup (c)nf (b)ackup solves the exhausted battery problem.

This procedure can be safely used for mentioned combination only, so main module serie 8 and base module and later. Older main module, e.g. E 730 can be replaced by newer E and complement it by new B


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