PTCRB certification and GCF certification debug analysis
(The situation set in this article is the situation of initial certification, which means that the designed product is certified by PTCRB for the first time, and no certified modules are added to the finished product. It is not a deformation certification, not a re-band, not an ECO etc., so the problems involved in the debug will be deeper. In addition, the examples here only involve the problems that occur in the Protocol and SIM tests, and other RF and OTA problems do not appear. Examples of how to use the test log and instruments technically Software to use fast positioning to find out the problem and realize fast debugging.)
PTCRB: PCS Type Certification Review Board, GCF: Global Certification Forum, PICS: Protocol Implementation Conformance Statement
Deeplight Technology obtains GCF certificate for customers
1. Introduction to PTCRB certification
PTCRB (PCS Type Certification Review Board) refers to the Personal Communication Service Type Certification Evaluation Committee, which was established in 1997 by North American mobile operators. The current operators are not limited to North America, but include mobile operator members worldwide. Its purpose is to provide type certification for end products and templates including Cellular GERAN (GSM), UTRAN (UMTS) and E-UTRAN (LTE).
PTCRB certification is a quasi-compulsory type certification performed by a third-party certification body. All PCS terminal equipment put on the North American market must pass PTCRB certification and apply for IMEI based on the report. The quasi-mandatory is used here, and the mandatory should be the requirements issued by the government regulatory department, but the PTCRB is not governmental, it is in the form of a forum, but it is very authoritative. The reason is that dealers entering North America must follow this requirement. Products provided by the test manufacturer are therefore called quasi-mandatory. PTCRB is also composed of operators and some large mobile phone manufacturers, as well as some accredited laboratories.
(IMEI can apply for PTCRB certification at the same time, and does not need a PTCRB report to apply. IMEI ID cards for similar products, regardless of whether they do PTCRB certification or not, wireless products should have their own TAC code, a TAC code plus the manufacturer‘s own The defined serial number can form an IMEI, and one TAC code can manage 1 million IMEIs. For wireless networks that do not use large North American operators, PTCRB certification is actually not required, but in fact there will be large-scale networks that do not use network coverage. The operator’s network, and the use of a small operator’s network, will often cause the wireless network to fail to connect, frequently disconnect the network, and even be troubled by illegal equipment, causing equipment manufacturers to have to apply for PTCRB certification)
2. Introduction to GCF Certification
Global Certification Forum, Global Certification Forum, GCF is an organization jointly established by operators and terminal manufacturers to ensure global interoperability of terminals through an independent certification process. It includes major GSM (or future UMTS) network operators and mainstream terminal manufacturers in the world, and invites test instrumentation developers to participate in GCF activities.
The role of GCF certification: The purpose of manufacturers is to quickly obtain new models to enter the market, and the purpose of operators is to provide attractive and reliable services.
How does GCF certification meet the previous goals: It defines the tests that each terminal must accept to ensure reliable and consistent behavior of the terminal. Make sure any endpoints that are GCF certified pass these tests. It is guaranteed that more and more complex techniques will be introduced in the future.
GCF certification is based on the principle of voluntary. Terminal manufacturers declare whether their products meet or exceed the requirements of certification standards based on GCF certification standards. Although GCF standards are not mandatory requirements, most countries and regions in the world currently require them The terminal manufacturer completes the test of the GCF certification standard, or refers to the GCF certification standard. In the European and North American markets, terminal product sales are combined with network operators (Operators), and general network operators will require terminal manufacturers to complete GCF testing for mobile phones (most of them require GCF certification).
Like the PTCRB test category, GCF also includes tests for RF, Protocol, SIM, Audio, etc.
(The two biggest differences between GCF certification and PTCRB certification: PTCRB certification does not require field testing, and GCF members need to pay an annual fee to pass the certification, and PTCRB needs to pay a listing fee for each certification)
3. PTCRB/GCF test classification
1. RF part test;
2. The test of the Protocol part;
3. The test of the SIM part;
4. Audio part test;
(In addition, there are OTA tests, AT commands and other tests)
5. Field Trail
GCF certification is an indispensable and important part. Its implementation is to ensure that terminal equipment can be used safely in the actual network environment. It can verify the intercommunication between networks and the performance of some new network services from the perspective of end users.
6. Application Test (Application Enabler)
Application tests in GCF certification include MMS, Video Telephony and other aspects of testing.
4. Classification of Conformance Test Protocols
(1) The RF conformance test protocol standard is as follows:
GSM:
1. 3GPP TS 51.010-1 GSM RF
UMTS:
2. 3GPP TS 34.121-1 UMTS RF
LTE:
3. 3GPP TS 36.521-1 LTE RF
4. 3GPP TS 37.571-1 LTE A-GNSS RF
(2) Protocol Conformance Test Protocol Standard
The protocol conformance criteria are as follows:
GSM:
1. 3GPP TS 51.010-1 GSM Protocol
WCDMA:
3. 3GPP TS 34.123-1 UMTS Protocol
4. 3GPP TS 34.124 UMTS RSE
LTE:
5. 3GPP TS 36.523-1 LTE Protocol
6. 3GPP TS 36.124 LTE RES
7. 3GPP TS 36.521-3 LTE RRM
8. 3GPP TS 37.571-2 LTE A-GNSS Protocol
9. 3GPP TS 34.229-1 IMS
(3) SIM card conformance test protocol standard
The Sim card conformance test protocol standard is as follows:
GSM:
1. 3GPP TS 51.010-4 GSM STK
UMTS:
1. 3GPP TS 31.121 UMTS USIM
2. 3GPP TS 31.124 UMTS USAT
3. ETSI TS 102 230 UICC
LTE:
1. 3GPP TS 31.124 LTE LSAT
2. 3GPP TS 31.121 LSIM
(The above information is for 2016. For the latest test standard PTCRB certification, please refer to PTCRB test standard NAPRD03, which is updated every quarter)
5. PTCRB/GCF Problem Analysis and Positioning
(1) Classification of certification test questions
PTCRB/GCF test, the problems reported by the laboratory as test fail can be basically divided into the following categories:
The capability information reported by the UE does not match the PICS statement.
Sim card consistency test issues, mainly STK issues.
2G/3G/4G network access issues, such as GSM/WCDMA/LTE random access, plmn manual/automatic network selection.
PDP activation and deactivation, network measurement in mobility management, handover, reselection, etc.
Application questions, such as sms, mms, AGPS, call, SS (supplementary service), etc.
(2) Basic analysis methods for certification issues
We mainly deal with protocol test fail issues. The laboratory will list the chapters of the test fail in detail, and provide the UE log of the test fail and the corresponding SS instrument log.
The general steps for dealing with GCF/PTCRB issues are as follows:
Find the protocol chapter of the fail problem, and check the test conditions and test steps of the case according to the protocol description.
Analyze the instrument log to find the error point of the instrument verdict fail. Different test instruments have different log analysis methods, and examples will be introduced later.
Analyze the UE log to determine whether the behavior of the UE is normal.
Analyze the comparison machine log. In many test cases, when the obvious error cause cannot be found from the instrument log or UE log, it is necessary to use the comparison machine log for comparison and analysis. Through the comparison machine test, it is also possible to more accurately judge whether the SS instrument problem or the test fail caused by the UE problem.
(3) Instrument log analysis
Instrument log analysis is very important in certification testing. If you can quickly find the instrument verdict fail point from the instrument log, it is very important to quickly and accurately locate the problem. Therefore, mastering the instrument log analysis method is the basic ability for authentication problem analysis.
RF/protocol/sim/audio, different test parts, different test instruments, and different laboratory test instruments may also be different. In the process of analyzing certification problems, it is necessary to communicate with the laboratory more, summarize more, and accumulate more to gradually improve the ability to analyze problems. The following introduces the basic testing equipment and has a general understanding of the testing equipment.
Certification Test Instrument Introduction
Major instrument manufacturers:
Japan Anritsu (ANRITSU)
German R&S
British ANITE
American AEROFLEX
American SPRIENT
IT3 platform
In our laboratory, the main instrument used is R&S. For some LTE test items, the R&S test will report an error, and only Anite can test it. These cases should be focused on in the future.
The test instruments we mainly contact are R&S, Anite and Anritsu ANRITSU, IT3 platform. Other instruments need to be gradually accumulated in the process of dealing with certification issues in the future.
(4) The following mainly introduces the basic methods of log analysis of the following instruments.
R&S instrument log analysis method
R&S instrument log analysis requires the installation of the CMWmarsViewer.exe tool, which is provided to us by the laboratory, and the path is as follows:
The screenshot of CMWmarsViewer.exe interface is as follows:
The screenshot of the instrument log provided by the laboratory is as follows:
The instrument log can be opened through file –>open->messagelog.msglog. The screenshot of the instrument log after the tool is opened is as follows:
You can view the specific content of the signaling through the message tree. It is easy to use and is very similar to Qualcomm‘s QXDM analysis tool QCAT. Filter NAS messages, enter nas in the ctrl + F search box, the query results are as shown in the figure below, and get all nas messages:
This keyword is very important. By searching for this keyword, we can see the error point of the instrument at a glance. In the above example, we can clearly see that the failure point of the instrument is: unexpected NAS PDU at port SRB. According to this clue, we can check whether the content of the NAS signaling reported by the UE meets the test requirements, which greatly reduces the scope of problem analysis.
The 1359190407_SeqDbgLog.txt file in these files can detect the verdict fail point of the instrument. As shown in the figure below, the test fail point:
From the instrument log, you can see the test fail point. The screenshot is as follows:
Error point: MMI shows abnormality, unexpected TERMINAL RESPONSE performed. According to this error point, we can analyze UE log to find out why UE sends wrong TERMINAL RESPONSE.
The screenshot of CMWmarsViewer.exe interface is as follows:
The screenshot of the instrument log provided by the laboratory is as follows:
The instrument log can be opened through file –>open->messagelog.msglog. The screenshot of the instrument log after the tool is opened is as follows:
You can use ctrl + F to search for keywords to filter the desired information. Example: To filter RRC messages, press ctrl + F to enter rrc in the search box, and the query results are as follows:
You can view the specific content of the signaling through the message tree. It is easy to use and is very similar to Qualcomm‘s QXDM analysis tool QCAT. Filter NAS messages, enter nas in the ctrl + F search box, the query results are as shown in the figure below, and get all nas messages:
Obtain the error point of the instrument through the verdict keyword:
This keyword is very important. By searching for this keyword, we can see the error point of the instrument at a glance. In the above example, we can clearly see that the failure point of the instrument is: unexpected NAS PDU at port SRB. According to this clue, we can check whether the content of the NAS signaling reported by the UE meets the test requirements, which greatly reduces the scope of problem analysis.
Anite instrument log analysis method, the provided Anite log screenshot is as follows:
The 1359190407_SeqDbgLog.txt file in these files can detect the verdict fail point of the instrument. As shown in the figure below, the test fail point:
Verdict fail: UnexpectedULMessage SMS. From the verfict fail point of the instrument, we can directly check the SMS message sent by the UE to find out the real cause of the fail.
The Anritsu instrument log needs to be converted into html format. The screenshot of the log is shown in the figure below:
Through index.html, you can query the detailed signaling process of the interaction between the instrument SS and the UE. You can also view the content of any signaling PDU.
You can query the instrument verdict fail point through TestStepDetails.html
IT3 platform instrument log analysis method, IT3 platform mainly tests SIM card consistency cases, such as stk, usat, etc. The instrument log needs to be converted into a word document in the laboratory. After converting into a word document, it is very easy to view the instrument log.
IT3 platform instrument log analysis method, IT3 platform mainly tests SIM card consistency cases, such as stk, usat, etc. The instrument log needs to be converted into a word document in the laboratory. After converting into a word document, it is very easy to view the instrument log.
The screenshot of the IT3 log provided by the laboratory is as follows:
From the instrument log, you can see the test fail point. The screenshot is as follows:
Error point: MMI shows abnormality, unexpected TERMINAL RESPONSE performed. According to this error point, we can analyze UE log to find out why UE sends wrong TERMINAL RESPONSE.
When IT3 tests 27.22.2, it may report that the PICS does not match. The method of analyzing this kind of problem is a little more complicated, which will be introduced in detail later.
Case study example: Unexpected Nas PDU causes AGPS test fail,
Description of the problem: 37.571-2 AGPS three cases 7.3.4.2-5S/ 7.3.4.4-5S/ 7.3.5.1-5S test fail, the reason for the laboratory feedback instrument Verdict fail is because the wrong NAS PDU is received. The AGPS problem is handled by the connection team. At first they suspected that it was an instrument problem and asked the laboratory to replace the Anite test. However, the comparison machine used in the laboratory can test the pass, so they refused to replace the instrument test.
After the problem is forwarded to us, according to the problem analysis steps, first analyze the instrument log to find the Verdict fail point of the instrument:
The instrument verdict fail point is:
The instrument verdict fail point is:
Mismatch on port SRB: Difference: SRB_COMMON_IND.Signalling.Nas[0].Pdu.Msg. The wrong nas signaling message is: ETC Test Loop Mode C MBMS Packet Counter Response.
Analyze the UE QXDM log. After analyzing the pass log and UE fail log of the comparison machine, it is found that after receiving the reset UE positioning Stored Info Msg from the SS, the UE returns a ULInformationTransfer to the SS, but the comparison machine does not have this NAS message. After Qualcomm parses out this ULInformationTransfer, it is the ETC Test Loop Mode C MBMS Packet Counter Response message.
From this, it can be judged that the UE sent this message and caused the instrument verdict to fail. The Log is as follows:
Further analysis and comparison machine pass log and UE fail log, the fail log is printed in the red box as shown below, when the Reset UE Positioning Stored Info of SS is received.
From the instrument log, it is found that the item38 expected value is 1, and the receive value is 0. The value reported by the UE does not match the PICS.
Further analysis and comparison machine pass log and UE fail log, the fail log is printed in the red box as shown below, when the Reset UE Positioning Stored Info of SS is received.
Because Qualcomm did not open this part of the code to us, we asked Qualcomm about the case, and Qualcomm later replied that it was indeed a problem with the UE. There was a bug in the MAC processing of the UE, and we applied for a patch to solve this problem.
Summary: This problem is actually not complicated to analyze. Analyzing and comparing the machine log can quickly find out the error point of the problem. The important thing is to master the method of instrument log analysis and comparative analysis method, so as to get twice the result with half the effort for the analysis problem.
(5) Sim card consistency test Terminal profile problem
Problem description: Test 31.124 27.22.2 The Terminal profile reported by the instrument does not match the Pics.
This kind of problem belongs to the first type of problem in the classification of authentication problems, and the UE‘s reporting capability does not match the PICS declaration.
For problem analysis, first analyze the IT3 instrument log, and the error points of the instrument log are as shown in the figure below:
From the instrument log, it is found that the item38 expected value is 1, and the receive value is 0. The value reported by the UE does not match the PICS.
The problem analysis steps are as follows: First, find the PICS item corresponding to item38, and find out from the instrument log that the PICS with item38 as 1 is C268
C268 - IF ‘Option 85’ THEN Mandatory ELSE Bit value="0" or bit not present
Open 3Gpp TS 31.124, search for C268, and find the corresponding PICS as shown below:
From the figure above, we can see that if you want item38 to be 1, you need to declare A.1/85 O_No_Type_NK as yes.
From the figure above, we can see that if you want item38 to be 1, you need to declare A.1/85 O_No_Type_NK as yes.
Search pics and found that the corresponding PICS item is: 31124_A.1/85 Terminal supports keypad PICS, this item is indeed stated as yes.
After finding the PICS item, decide whether to modify the UE software or modify the PICS according to the requirements and product characteristics. In addition, the analysis method of item42 and item68 is the same.
(6) Need to replace Anite instrument test problem
Problem description: 3GPP TS 34.123-1 8.2.2.53, 3GPP TS 34.123-1 8.3.1.47, 3GPP TS 34.123-1 8.3.4.11
The laboratory test of these three cases failed, and the previous certifications were retested only after replacing Anite.
Problem analysis: 8.2.2.53 and 8.3.4.11 are the same problem, the R&S instrument judges the CQI interval incorrectly, which leads to the misjudgment of the instrument.
Log analysis is as follows: the instrument checks the CQI transmission interval of UE‘s CFN 148 subframe 1 and subframe 3 before the UE enters dtx-Cycle2, resulting in a test fail.
The relevant logs are as follows:
//SS configuration UE DTX UE enters dtx-Cycle2 time point 22:48:47. 351:
22:48:44.885 [03] 0x412F WCDMA Signaling Messages -- DL_DCCH Radio Bearer Setup
22:48:47.346 [F9] 0x412F WCDMA Signaling Messages -- UL_DCCH Radio Bearer Setup Complete
22:48:47.351 [F9] 0x422C CPC DTX State Machine
// CFN 148 subframe 1 and subframe 3 send CQI time point 22:48:46.189
22:48:46.189 [85] 0x421C UL HS DPCCH Information Log Packet Edition 2
| 740| 0| R| 30| | | | D|
| 741| 0| R| | | | | D|
| 742| 0| R| 30| | | | D|
| 743| 0| R| | | | | D|
| 744| 0| R| 30| | | | D|
| 745| 0| R| | | | | D|
| 741| 0| R| | | | | D|
| 742| 0| R| 30| | | | D|
| 743| 0| R| | | | | D|
| 744| 0| R| 30| | | | D|
| 745| 0| R| | | | | D|
// 201/221/241/281 You can see that the CQI is sent every 20 subframes.
22:48:53.762 [25] 0x421C UL HS DPCCH Information Log Packet Edition 2
Version = 3
Num Samples = 100
Secondary Carriers = 0
HS-DPCCH Slot Format = 0
-------------------------------------------------------------------------------------------------------
|Sub | |CQI |Cqi |Cqi |Cqi |Cqi |AckNackDtx|AckNackDtx|AckNackDtx|AckNackDtx|
|Fr# |hsCqiReport|Type|Carrier0|Carrier1|Carrier2|Carrier3|Carrier0 |Carrier1 |Carrier2 |Carrier3 |
--------------------------------------------------------
201| 0| R| 30|
221| 0| R| 30|
241| 0| R| 30| | | | D| |
261| 0| R| 30| |
281| 0| R| 30|
Num Samples = 100
Secondary Carriers = 0
HS-DPCCH Slot Format = 0
-------------------------------------------------------------------------------------------------------
|Sub | |CQI |Cqi |Cqi |Cqi |Cqi |AckNackDtx|AckNackDtx|AckNackDtx|AckNackDtx|
|Fr# |hsCqiReport|Type|Carrier0|Carrier1|Carrier2|Carrier3|Carrier0 |Carrier1 |Carrier2 |Carrier3 |
--------------------------------------------------------
201| 0| R| 30|
221| 0| R| 30|
241| 0| R| 30| | | | D| |
261| 0| R| 30| |
281| 0| R| 30|
8.3.1.47 We have analyzed the UE QXDM log in detail. According to the test regulations, step4, the cell update confirm sent by the SS to the UE, and analyzing the physical layer log, we can see that the UE has received 3 pass PDUs, and the UE can correctly parse this frame and passed to the MAC layer. According to the test regulations, because the UE-ID unmatched in the cell update confirm, the UE will eventually discard this signaling.
In step5 UE resends cell update.
Step6, SS resends the cell update confirm, but analyzing the cell update confirm sent by the step6 SS, it is found from the physical layer log that the UE only receives 2 pass PDUs, so the UE directly discards this frame at the physical layer, resulting in the UE not receiving To the Cell update confirm sent by SS.
The log is as follows:
The cell update confirm log packet received in Step4 has 3 pass PDUs.
22:57:44.875 [E2] 0x4222 HS Decode Status Log Packet with Data Edition 3
|----|----|----|-----|--|---|---|---|-----|----|
| # |SCCH|DSCH|HS TB|RV|New|Num|Cod| |HARQ|
| |A/V |Stat| size| | Tx|Cod|Off| Mod | Id|
|1151|1 1 |PASS| 272| 0| 1| 1| 1| QPSK| 2|
|1152|1 0 | DTX| | | | | | | |
|1153|1 1 | DUP| 272| 0| 0| 1| 1| QPSK| 2|
22:57:44.925 [E7] 0x4222 HS Decode Status Log Packet with Data Edition 3
Carrier 0:
|----|----|----|-----|--|---|---|---|-----|----|
| # |SCCH|DSCH|HS TB|RV|New|Num|Cod| |HARQ|
| |A/V |Stat| size| | Tx|Cod|Off| Mod | Id|
|----|----|----|-----|--|---|---|---|-----|----|
|1156|1 1 |PASS| 272| 0| 1| 1| 1| QPSK| 3|
|1161|1 1 |PASS| 272| 0| 1| 1| 1| QPSK| 4|
| # |SCCH|DSCH|HS TB|RV|New|Num|Cod| |HARQ|
| |A/V |Stat| size| | Tx|Cod|Off| Mod | Id|
|1151|1 1 |PASS| 272| 0| 1| 1| 1| QPSK| 2|
|1152|1 0 | DTX| | | | | | | |
|1153|1 1 | DUP| 272| 0| 0| 1| 1| QPSK| 2|
22:57:44.925 [E7] 0x4222 HS Decode Status Log Packet with Data Edition 3
Carrier 0:
|----|----|----|-----|--|---|---|---|-----|----|
| # |SCCH|DSCH|HS TB|RV|New|Num|Cod| |HARQ|
| |A/V |Stat| size| | Tx|Cod|Off| Mod | Id|
|----|----|----|-----|--|---|---|---|-----|----|
|1156|1 1 |PASS| 272| 0| 1| 1| 1| QPSK| 3|
|1161|1 1 |PASS| 272| 0| 1| 1| 1| QPSK| 4|
The cell update confirm log packet received in Step6 has only 2 pass PDUs.
22:57:52.875 [02] 0x4222 HS Decode Status Log Packet with Data Edition 3
Carrier 0:
|----|----|----|-----|--|---|---|---|-----|----|
| # |SCCH|DSCH|HS TB|RV|New|Num|Cod| |HARQ|
| |A/V |Stat| size| | Tx|Cod|Off| Mod | Id|
|----|----|----|-----|--|---|---|---|-----|----|
| 11|1 1 |PASS| 272| 0| 1| 1| 1| QPSK| 0|
| 15|1 1 | DUP| 272| 0| 0| 1| 1| QPSK| 0|
| 16|1 1 |PASS| 272| 0| 1| 1| 1| QPSK| 1|
| # |SCCH|DSCH|HS TB|RV|New|Num|Cod| |HARQ|
| |A/V |Stat| size| | Tx|Cod|Off| Mod | Id|
|----|----|----|-----|--|---|---|---|-----|----|
| 11|1 1 |PASS| 272| 0| 1| 1| 1| QPSK| 0|
| 15|1 1 | DUP| 272| 0| 0| 1| 1| QPSK| 0|
| 16|1 1 |PASS| 272| 0| 1| 1| 1| QPSK| 1|
Summarize
GCF certification/PTCRB certification problem analysis, in addition to mastering the correct analysis method, also requires a wealth of knowledge accumulation, thick and thin, to analyze problems quickly, efficiently and accurately. Because the certification issues involve a wide range and involve many modules. Therefore, in the process of solving problems, you should diverge more. In addition to the problem itself, you can also carefully study and understand the modules involved in the problem, which is very helpful for the accumulation of knowledge.
For the usual accumulation, it is recommended to read more about the 3GPP protocol to understand the implementation details of the protocol. You can read the protocol chapters while looking for the corresponding code, which is very helpful for understanding the protocol. It is also good for understanding code implementation logic.
The original material of this article comes from the author of CSDN "Twenty-Eight Mu Field 2014". Because the content of the article is detailed and professional, it is shared. Shenguang Laboratory will give supplementary explanations for some outdated and missing information. Welcome to read.
Deeplight Technology has carried out PTCRB certification and GCF certification all year round. We have a team of project managers and engineers who have more than ten years of experience in handling such PTCRB certification and GCF certification projects. Over the years, we have helped many listed companies obtain PTCRB certification and GCF certification. I hope it will be helpful to customers who want to apply for PTCRB certification and GCF certification. Welcome to consult our evaluation communication on the previous project.
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