A few initial EM7565 observations

Bjørn Mork bjorn at mork.no
Sat Jan 27 13:04:53 UTC 2018


Bjørn Mork <bjorn at mork.no> writes:

> 2) as noted by Sebastian: does not seem to aggregate more than 2
>  cells. Both AT cli and QMI shows only 1 active or configured secondary
>  cell, even when downloading at max capacity (or limited by USB2)

Good news! User 'westrem' (a "ROOter" user), found that 3xCA was enabled
by locking the modem to a specific band:
https://forum.sierrawireless.com/viewtopic.php?f=117&t=10993&sid=a0bb62ce637cbbe3c951e0616440ab1e

Since my operator doesn't have 3 channels available in any single band,
I tried the same by locking to 2 bands (B3+B7):

 at!band=10,"my",0000000000000000,0000000000000044
 at!band=10


and it worked! Got

at!gstatus?
!GSTATUS: 
Current Time:  1022             Temperature: 37
Reset Counter: 1                Mode:        ONLINE         
System mode:   LTE              PS state:    Attached     
LTE band:      B3               LTE bw:      20 MHz  
LTE Rx chan:   1450             LTE Tx chan: 19450
LTE SSC1 state:ACTIVE           LTE SSC1 band: B7     
LTE SSC1 bw  : Unknown          LTE SSC1 chan: 3050
LTE SSC2 state:ACTIVE           LTE SSC2 band: B7     
LTE SSC2 bw  : Unknown          LTE SSC2 chan: 3248
LTE SSC3 state:NOT ASSIGNED
LTE SSC4 state:NOT ASSIGNED
EMM state:     Registered       Normal Service 
RRC state:     RRC Connected  
IMS reg state: No Srv  
 
PCC RxM RSSI:  -64              PCC RxM RSRP:  -77
PCC RxD RSSI:  -79              PCC RxD RSRP:  -96
SCC1 RxM RSSI: -61              SCC1 RxM RSRP: -87
SCC1 RxD RSSI: -72              SCC1 RxD RSRP: -99
SCC2 RxM RSSI: -58              SCC2 RxM RSRP: -84
SCC2 RxD RSSI: -75              SCC2 RxD RSRP: -102
Tx Power:      20               TAC:         79e1 (31201)
RSRQ (dB):     -6.9             Cell ID:     010caa02 (17607170)
SINR (dB):     16.4
 
 
OK


and qmicli returned this:

root at miraculix:/etc# qmicli -p -d /dev/cdc-wdm1  --nas-get-lte-cphy-ca-info
[/dev/cdc-wdm1] Successfully got carrier aggregation info
DL Bandwidth: '20'
Primary Cell Info
        Physical Cell ID: '176'
        RX Channel: '1450'
        DL Bandwidth: '20'
        LTE Band: 'eutran-4'
Secondary Cell 1 Info
        Physical Cell ID: '284'
        RX Channel: '3050'
        DL Bandwidth: '20'
        LTE Band: 'eutran-8'
        State: 'activated'
        Cell index: '1'
Secondary Cell 2 Info
        Physical Cell ID: '491'
        RX Channel: '3248'
        DL Bandwidth: '20'
        LTE Band: 'eutran-8'
        State: 'activated'
        Cell index: '2'


Ignoring the band number off-by-one, this all looks good to me!

Still not entirely sure abut the "Cell index" though.  I've assumed that
was an index into the table returned by --nas-get-cell-location-info,
but that table is often useless on the EM7565.  Looks like it returns a
sane set of bands and channels, and number of cells on each channel.
But the per-cell data is empty:

root at miraculix:/etc# qmicli -p -d /dev/cdc-wdm1   --nas-get-cell-location-info
[/dev/cdc-wdm1] Successfully got cell location info
Intrafrequency LTE Info
        UE In Idle: 'no'
        PLMN: '24201'
        Tracking Area Code: '31201'
        Global Cell ID: '17607170'
        EUTRA Absolute RF Channel Number: '1450' (E-UTRA band 3: 1800+)
        Serving Cell ID: '176'
        Cell [0]:
                Physical Cell ID: '176'
                RSRQ: '-7.5' dB
                RSRP: '-93.5' dBm
                RSSI: '-66.0' dBm
Interfrequency LTE Info
        UE In Idle: 'no'
        Frequency [0]:
                EUTRA Absolute RF Channel Number: '3050' (E-UTRA band 7: 2600)
                Selection RX Level Low Threshold: '0'
                Cell Selection RX Level High Threshold: '0'
                Cell [0]:
                        Physical Cell ID: '0'
                        RSRQ: '0.0' dB
                        RSRP: '0.0' dBm
                        RSSI: '0.0' dBm
                        Cell Selection RX Level: '0'
                Cell [1]:
                        Physical Cell ID: '0'
                        RSRQ: '0.0' dB
                        RSRP: '0.0' dBm
                        RSSI: '0.0' dBm
                        Cell Selection RX Level: '0'
                Cell [2]:
                        Physical Cell ID: '0'
                        RSRQ: '0.0' dB
                        RSRP: '0.0' dBm
                        RSSI: '0.0' dBm
                        Cell Selection RX Level: '0'
                Cell [3]:
                        Physical Cell ID: '0'
                        RSRQ: '0.0' dB
                        RSRP: '0.0' dBm
                        RSSI: '0.0' dBm
                        Cell Selection RX Level: '0'
        Frequency [1]:
                EUTRA Absolute RF Channel Number: '3248' (E-UTRA band 7: 2600)
                Selection RX Level Low Threshold: '0'
                Cell Selection RX Level High Threshold: '0'
                Cell [0]:
                        Physical Cell ID: '0'
                        RSRQ: '0.0' dB
                        RSRP: '0.0' dBm
                        RSSI: '0.0' dBm
                        Cell Selection RX Level: '0'
                Cell [1]:
                        Physical Cell ID: '0'
                        RSRQ: '0.0' dB
                        RSRP: '0.0' dBm
                        RSSI: '0.0' dBm
                        Cell Selection RX Level: '0'
                Cell [2]:
                        Physical Cell ID: '0'
                        RSRQ: '0.0' dB
                        RSRP: '0.0' dBm
                        RSSI: '0.0' dBm
                        Cell Selection RX Level: '0'
                Cell [3]:
                        Physical Cell ID: '0'
                        RSRQ: '0.0' dB
                        RSRP: '0.0' dBm
                        RSSI: '0.0' dBm
                        Cell Selection RX Level: '0'
                Cell [4]:
                        Physical Cell ID: '0'
                        RSRQ: '0.0' dB
                        RSRP: '0.0' dBm
                        RSSI: '0.0' dBm
                        Cell Selection RX Level: '0'
LTE Info Neighboring GSM
        UE In Idle: 'no'
LTE Info Neighboring WCDMA
        UE In Idle: 'no'




The "Cell index" also has no meaning wrt this data structure, since the
the two secondary cells obviously will be on different channels.  Maybe
it is a frequency index?  Or maybe its just a local index for the
secondary cell table?  Which seems a bit pointless, I must admit.

Well, it doesn't matter much I guess.  We have the most important data.



Bjørn


More information about the libqmi-devel mailing list