Q1: What’s the difference between Rate Control on Iub and RAB Modify? What are their application scenarios respectively?
A1: Rate Control is in user plane while RAB Modify is in control plane (RANSAP), which is the main difference. After usable RFCI set is negotiated during user plane initialization, Rate Control can modify exact RFCI without the changes of RAB. RAB Modify is used more frequently, e.g. when QoS can’t be supported by previous RABs any more, RAB Modify is needed. If you want more information, please refer to TS 25.415 and TS 25.413.

Q2: ASN is used to describe the protocols on Iu, Iub and Iur interfaces. Are there any domestics suppliers are focusing on ASN R&D? Is ASN R&D familiar with common communication protocol R&D?
A2: Sorry for no such information and perhaps related suppliers have more.

Q3: What’s the emphasis in current terminal performance testing? Would you please give some information regarding conformance testing environment? So far, there is no available conformance testing system. Then how to guarantee the quality of terminals? Can you introduce the status of the abuilding field testing environment? Which solution is selected for UICC/USIM conformance testing?
A3: Terminal performance testing is focusing on RF performance testing and terminal power consumption testing. Terminal performance under practical radio environment also should be considered such as long time call capability, call quality under different moving speed etc. 2G and WCDMA conformance testing rely on the third testing system which is authorized by related organizations such as CCF etc. The R&D of TD-SCDMA conformance testing system is ongoing now.
The standardization process of terminal software performance testing has been started.
TD-SCDMA machine/card conformance testing can sharing the same platform with WCDMA. ORGA can be used for electric performance testing. TD-SCDMA machine/card conformance testing has not been started.

Q4: When testing outing power control function, how to test transmitting power on uplink pilot channel? Besides TAS4500, are there any other systems can be used for multipath simulation, such as SMU200 or the software provided by Agilent?
A4: Outing power control has three cases: high, medium and low. -108 and -66 cases can use visual trigger to catch SYNC UL. Because the leaking power form TS0 is about -25, -25 case can’t use visual trigger but max hold. Perhaps one time is not enough and multiple attempts or longer scanning time are needed.
Because multipath is needed in SS downlink simulating signal. TAS4500 is very convenient for usage. C2 also can be used. If we want to use SMU200A, base band signal is needed as input and multi path is added to it before output. Because of the heavy workload and the consideration of testing period, TAS4500 is used. It is difficult to meet the requirement for multipath case 2. How to resolve it is under discussion.

Q5: There is an example of TD-SCDMA multiframe in 3GPP standard which says 64 radio frames make a multiframe. Whether the length of multiframe is fixed (like GSM’s 51 or 26) or it can be defined via system information? If it can be configured, the definition is in SIB5 or other blocks? Whether it means 4096 is a multiframe in TDD system following FDD system?
A5: There is no the concept of multiframe in formal 3GPP specifications although it ever appeared in the very beginning.

Q6: Commercial TD-SCDMA usage is coming. Is there a huge demand of testing instrument?
A6: Testing instrument is the focus for next step. It is sure that lots of testing instrument is needed in future. Currently RF instrument is very lacking.

Q7: How to calculate the maximum 23 voice users within one TD-SCDMA carrier?
A7: The time slots are configured as UL/DL 3:3. A pair of time slot code resource can support 8 AMR users. 3 pairs can reach 24 AMR users. When considering that PRACH occupies one uplink code unit (such as one SF=8 Channel Code), we can conclude that 24-1=23 AMR voice users. Under given environment and scenario, TD-SCDMA capacity is code resource limited.

Q8: Does joint detection have commercial solution? Is RAKE receiver used to conquer MAI?
A8: Current equipments adopt commercial joint detection solution.

Q9: Compared with FDD system, how about the status of TD-SCDMA Iub interface IOT?
A9: During 3G Testing and Industrialization Project, RNC and NodeB from different suppliers have been connected with each other. The result of Iub interface testing is very good.

Q10: Which version does the abuilding field trial comply with, R4 or R5?
A10: Equipments used for field trial follow CCSA industrial standard, 3GPP R4 2003.03 version.

Q11: May I know current testing is based on common frequency network or different frequency network? Can we resolve the problem of common frequency network? Do we have mature commercial solution to this issue? To reduce the interference on public channel, frequency division is used in TDD initial stage, is it true? Although the solution is correct in theory, there are lots of difficulties in practical operation, is it true?
A11: Both common frequency and different frequency networks have been tested in field trial. Other question will be answers later.

Q12: In the protocol stacks of Iu, Iub interfaces, there are two parts: one is SSCOP SSCF SCCP and the other is IP SCTP M3UA. How to differentiate these two parts?
A12: Both of them are transport bearer. When we realize the interface protocol, just one is enough. Currently SSCOP is more popular.

Q13: Can TD-SCDMA support HSDPA to achieve 14.4 Mbps throughput? Can we enhance the throughput via better coding such as LDPC? In next version, will TD-SCDMA adopt OFDM or other technologies? Does SC-FDMA mean single carrier? How about the status of domestic TD-SCDMA HSDPA R&D?
A13: In 3GPP R5, TD-SCDMA can support HSDPA. Because its narrow carrier band width, it can’t support 14.4 Mbps, but 2.8 Mbps in 3GPP R5. In fact, 14.4 Mbps is also difficult for WCDMA HSDPA. CCSA is discussing how to enhance TD-SCDMA downlink data rate now. There is a project of LTE in3GPP, in which LDPC and Turbo coding is on discussion. OFDM is an optional technology for both FDD and TDD systems. Regarding other technologies, there are SC-FDMA and MC-CDMA etc.
SC-FDMA means single carrier. It is true.
So far, we have little information for domestic TD-SCDMA HSDPA R&D.

Q14: Multi-path signal is produced by signal generator. Can I do the testing by the comparison between the code decoded from terminal and the transmitting code? How to calculate the BER in RF testing? Can K1297 do this?
A14: This testing method is generally used on product line when suppliers want to do the testing by themselves. K1297 + NodeB can act as a system simulator and K1297 is used for statistic. If the signal is from a signal generator, the generator can do the statistic by itself.

Q15: During the user data and signaling transmission, does the AAL2/ AAL5 VCI VPI is assigned by ALCAP? How to differentiate the cell is from AAL2 or AAL5? Does all signaling is transmitted by AAL5?
A15: ALCAP dynamically allocates VCI/VPI to AAL2 for user plane data transmission. Generally signaling bearer adopts fixed allocation mode. In most cases, the differentiation of AAL2 and AAL5 link depends on the different combination of VCI and VPI on the interfaces. Additionally, CPS PDU in AAL2 and AAL5 has different format.
On Iu/Iub/Iur interfaces, all the signaling is transmitted over AAL5 link.

Q16: Is commercial sectored smart antenna available now? Does it also use plane antenna array? Does sectored NodeB join the testing?
A16: Sectored smart antenna adopts line antenna array. Both omni and sectored NodeBs joined the testing. According to currently available equipments, sectored NodeB is based on line array smart antenna and omni NodeB based on circle array smart antenna.

Q17: In GSM system, SMS uses SDCCH and needs no dedicated channel. How to realize SMS transmission in TD-SCDMA system?
A17: SMS can be transmitted on FACH or DCH.

Q18: Is full synchronization needed between different NodeBs? Is there some chip phase shift?
A18: According to the requirements in TD-SCDMA specification, full inter-NodeB synchronization is needed. The synchronization precision is limited by practical realization.

Q19: In CDMA system, RAKE receiver is necessary for both uplink and downlink. Joint detection is used on uplink. Will downlink without JD lead to system downlink limitation?
A19: For downlink, the gain from the beamforming of smart antenna should be taken into account.

TOP-->