`Exhibit 1005
`
`ZTE Corporation and ZTE (USA) Inc.
`ZTE Corporation and ZTE (USA) Inc.
`
`
`
`TSG-RAN Working Group 1 #22
`Torino, Italy, Aug. 27-31 2001
`
`R1-01-0810
`
`Source:
`
`Title:
`
`InterDigital Comm. Corp.
`
`Implicit UE Identification for HSDPA Downlink Signaling
`
`Document for:
`
`Discussion
`
`Introduction
`1.0
`Reference [2] proposed two encoding strategies for the HS-PDSCCH that eliminate the need
`for explicit UE ID when an HS-DSCH Indicator (HI) is present.
`These were:
`¯ A UE specific scrambling code
`¯ A UE-specific CRC
`
`In the second strategy, a UE-specific CRC may be constructed by requiring that the 16-bit
`MAC UE ID be concatenated with the control information and passed through the CRC
`generator polynomial. As a result, the CRC generated will be a function of the UE ID.
`However, the UE ID is never transmitted over the air.
`
`This document supports the use of the UE-specific CRC because it is simple and effective
`and applicable equally to FDD and TDD.
`
`In the discussion of reference [2] in Espoo, InterDigital Comm. Corp. supported the basic
`approach of UE-specific CRC, but suggested that there are other implementations that may
`provide the same fundamental benefit with somewhat simpler implementation.
`
`This contribution identifies two alternative implementations for the UE-specific CRC.
`
`2.0 Review of Concatenation Approach
`
`The UE-specific CRC method described in [2] is implemented by using the MAC UE ID
`concatenated with control information to generate CRC as depicted in the figure below:
`X
`M
`N
`
`HS-DSCCH
`
`CRC
`Generator
`
`The common control channel HS-DSCCH carries UE specific control information as shown
`below:
`
`X
`
`N
`
`HS-DSCCH
`
`NK8681TC015906751
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1005-00001
`
`
`
`3.0 Alternative Implementations
`
`This section defines two alternative implementations, which provide benefits of the UE-
`specific CRC.
`
`Alternative 1 - First generate the N bit CRC, independent of UE ID. Then, modulo 2 add the
`N-bit CRC with the M-bit MAC UE ID. If M<N, the UE ID is zero padded with M-N leading O’s
`or trailing O’s. Here, the CRC is used to provide higher protection for the UE-specific control
`information carried on HS-DPSCCH. If M >N, the M-N least significant bits of the UE ID are
`truncated prior to the module 2 addition with the CRC field
`M
`
`X
`
`HS-DSCCH
`
`CRC
`Generator
`
`The code multiplexed HS-DSCCH carrying UE specific control information contains
`embedded UE ID as shown:
`X
`N
`Mask
`HS-DSCCH CRC
`
`Alternative 2 - In step 2, initialize the CRC generator (i.e., the shift-register) by UE ID value
`prior to CRC generation for the HS-PDSCCH as shown:
`
`X
`
`HS-DSCCH
`
`N
`
`CRC
`Generator
`
`The code multiplexed HS-DSCCH carrying UE specific control information in alternatives 2
`contains embedded UE ID as shown:
`X
`N
`
`HS-DSCCH
`
`All three UE-specific CRC approaches have the same error protection capability; proportional
`to 2-a, where N is the length of the CRC. However, considering the complexity, we propose
`use of implicit UE identification described as alternative 2, due to the fact that this method
`does not require assembly and disassembly of UE ID with the HS-DSCCH, at transmitting or
`receiving end, as required by UE-specific CRC method described in [2].
`
`4.0 Performance
`
`NK8681TC015906752
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1005-00002
`
`
`
`For all the candidates discussed, the error detection protection is on the order of 2-N, where N
`is the size of the CRC.
`
`5.0 Conclusion
`
`Implicit UE ID encoding via a UE-specific CRC is recommended. It is simple, effective, and
`equally applicable to FDD and TDD.
`
`Three alternative implementations have been discussed, one from reference [2] and two
`additional alternatives in this contribution.
`
`All will provide the same level of protection, and the least complex version should be
`selected.
`
`InterDigital’s complexity analysis has judged that the simplest, and therefore preferred
`approach is to initialize the N-stage CRC shift register with N bits from the UE ID.
`
`[1] TSGR1#21(01) 0745, "Reliability Issues for Downlink Signaling in High Speed Downlink
`Packet Access (HSDPA)", Motorola
`[2] TSGR1#21(01) 0758, "Comments on the Requirement for UE ID when HI bit is present",
`Motorola
`
`NK8681TC015906753
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1005-00003
`
`