Module HL7588 Geolocation triangulation

IoT Modules
1

In order to get better geolocation, we want to use triangulation. The geolocation APIs we have access to require the full E-CGI cell tower ID for any triangulation, and the timing advance value for good triangulation.

The HL7588 KCELL and XCELLINFO commands only provide a physical ID for neighbor cells, which I understand may change as cell tower antennas are added and upgraded. They also only provide the timing advance for the serving cell tower.

The CGED command by documentation provides the full E-CGI cell tower IDs for neighbors, but in our experiments it has always returned an empty list, and I think it is a 3G solution which is going away.

I request a firmware update that returns the E-CGI Cell IDs and timing advances for neighbor cells, something like I think is now available for the HL7800 module.

2

Hi @michael.scudder,

1, Is your module using the latest offical FW? You can get the latest offical FW at this page: https://source.sierrawireless.com/resources/airprime/software/hl7588-firmware/#sthash.9XvMRjI4.dpbs

2, Can you send me your log after sending +CGED command to module?

Thanks,

3

No, it turns out we are not using the latest official FW. I have two different boards, the one which I had tested before, which is running RHL75xx.A.2.20.151600.201903181615.x7160_1
and another which is running RHL75xx.A.2.13.151600.201802201800.x7160_1 (both of these strings are the output of a ATI3 command).

The output of the first board’s +CGED=0 command is very simple:

send (AT+CGED=0^M)
expect (OK)

AT+CGED=0

OK
– got it

While the 2nd board, the one I had not tested before, outputs much more information:

send (AT+CGED=0^M)
expect (OK)

AT+CGED=0

+CGED: RAT:“UMTS”,

URR:“ID”

DC:002, BP:0010, M:004, ERR: 0, RC:41, OOS:0,

BLER:-,TSIR:-,MSIR:-,DPUC:-,DPDC:-,UPUC:-,UPDC:-,CMOD:-

TPCA:0, DCL:0, UPCS:0, BTRG:1, NHSC:0

HCS:0, HMD:0, LM:0,

CMAX:31, CMEAN:31, CMIN:31, AFTI:255, ATYP:255

RJCZ:0

Cell-ID:ffffffff, DLF:65535, ULF:65535, C:0, D:0, PSM: 0

Cell:G, B:- Arfcn:- RxLev:- Bsic:- RV:-,

RR measurement evaluation:

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MeasId: 0, EventId: 0A, 0, 0, 0, 0, 0, 0

MM:

Process:CO, MMs: 4, MMSs: 0, MSC:B, T: 0

Process:CS, MMs:32, MMSs: 5, LUS:1, T:0000, L:0

Process:PS, MMs:20, MMSs: 1, LUS:1, T:0000, L:0, GS:False, R:0

Cell change counters:

CRT: 0, IRCR: 0

AIRCR: 0, IRHO: 0, AIRHO: 0

Serving PLMN:

MCC:0, MNC:0, LAC:65535, RAC:255

Equivalent PLMNs:

MCC:310, MNC:260

OK
– got it

Note that I had also had a colleague in a more suburban (my location is rural) environment test another board, which gave the same empty result for the +CGED=0 command.

I will pursue updating the firmware on at least one of these boards.

Do you expect the +CGED=0 command with the latest firmware to provide the E-CGI Ids for multiple neighboring LTE cell towers?

Thanks,
Mike S.

4

Note that our newest firmware version, RHL75xx.A.2.20.151600.201903181615.x7160_1, seems to be later than the latest AT&T version on the link you shared. Not sure how we ended up with it.

5

What version of firmware do you recommend we use?

Should the AT+CGED=0 command work on that version of firmware?

Thanks,
Mike S.

6

Hi @michael.scudder ,

Please try to use the official FW posted in Sierra source page following the link. It is validated by Sierra. According to the AT command user gude of HL7588, AT+CGED=0 command is supported. Please try and share your result
FW link
https://source.sierrawireless.com/resources/airprime/software/hl7588-firmware/#sthash.5SdKpMnb.dpbs
AT command link:
https://source.sierrawireless.com/resources/airprime/software/airprime_hl7588_at_commands_interface_guide/#sthash.9L6FDFKG.dpbs
Thanks