Exhibit 1019
`Exhibit 1019
`
`ZTE Corporation and ZTE (USA) Inc.
`ZTE Corporation and ZTE (USA) Inc.
`
`

`
`Inv. No. 337-TA-868
`RX-3070
`
`R1-02-1149
`
`3GPP TSG-RAN WG1#28
`Seattle, USA
`August 19-22, 2002
`
`Agenda item:
`
`HSDPA
`
`Source:
`
`Title:
`
`Lucent Technologies
`
`Code reuse in HSDPA
`
`Document for:
`
`Discussion
`
`1
`
`Introduction
`
`Thc orthogonal code spacc is an important systcm rcsourcc for WCDMA DL transmission, fhc orthogonal
`transmission is achieved by allocating OVSY codes to different control and data channels. For HS-DSCH, multiple
`SF=16 codes can be used for DL transmission ~,Athin a subframe. The HS-DSCH provides a highly efficient radio link
`and can potentially support a large number of users. However, the capacity of the HS-DSCH can be limited due to a
`shortage of available o~thogonal codes Ill. The shortage of codes can result due to various reasons including
`inet~icient code space usage by associated DPCCH and other dedicated cham~els. This can result in a
`disproportionately large amount power available t-or HS-I)SCH as compared to codes.
`
`In this paper, we discuss the effect of such an inefficient code usage, and the resulting code limitation, on HSDPA. We
`also suggest that code reuse can alleviate the problem.
`
`2
`
`Effect of Code Limitation on HSDPA
`
`In this scction, we show how codc limitation can substantially constrain the throughputs achicvcd in HSDPA.
`Precisely-, we present the OTA and service throughput attained using single antenna (i.e., no transmit diversity) and
`CLTD Mode-1. In particular, we consider two cases: one where only 25% of the code space is available for HSDPA
`(i.e., the system is code space constrained) and another where 62.5% of the code space is available (i.e., the system is
`not code space constrained). In both cases, 63% of the overall power fiaction is assLuned to be available for HSDPA.
`Figure 1 and Figure 2 below plot the OTA and service throughl~ut attained m each of the above cases Observe that in
`the code-constrained case, the service throughput and OTA remain virtually unchanged as the load in the system
`measured in terms of the number of UEs increase. This is a result of the fact that the system is peak-rate limited due to
`the code-space constraint.
`
`NK8681TC013089465
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1019-00001
`
`

`
`35OO
`
`3000
`
`2500
`
`2000
`
`1500
`
`I000
`
`500
`
`0
`
`35OO
`
`3000
`
`2500
`
`2000
`
`1500
`
`1000
`
`5OO
`
`0
`
`] SA (25% code space)
`
`[] CLTD (25% code space)
`
`[] SA (62.5% code space)
`
`[] CLTD (62.5% code space)
`
`37 UEs
`
`56 UEs
`
`75 UEs
`
`100 UEs
`
`Figure 1. OTA with single antenna and CLTD Mode-1
`
`] SA (25% code space)
`[] CLTD (25% code space)
`
`[] SA (62.5% code space)
`
`[] CLTD (62.5% code space)
`
`37 UEs
`
`56 UEs
`
`75 UEs
`
`100 UEs
`
`Figure 2. Service throughput with single antenna and CLTD Mode-1
`
`3
`
`Code Reuse
`
`The code shortage problem can party be resolved by using higher coding rates and high order modulations. However,
`the high coding rates and higher order modulations come with associated penalty thus impacting the overall system
`capacity. Moreover, in some cases, the higher order modulations may not be available. For example, the HS-DSCH
`supports QPSK and 16-QAM modulations only. MIMO technique can also solve the code limitation problem but it
`needs multiple transmit and multiple receive antennas.
`
`With the availability of 2 transmit antennas, both open loop (STTD) and closed loop (TxAA) transmit diversity
`schemes can be used for HS-DSCH [2]. The transmit diversity schemes provide link performance improvement
`leading to overall system capacity improvements. However, the gains achieved by the transmit diversity schemes can
`
`NK8681TC013089466
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1019-00002
`
`

`
`be small when fl~e system is code limited. This is due to fl~e l~act that transmit diversity provides power benefit by
`achieving a given performance with smaller power (Ec/Ior) required compared to a single antenna transmission.
`
`The basic principle adhered to in scheduling with code reuse is to ensure that users selected on each antenna have
`good ’%ross-antenna rejection". That is, a user scheduled on antenna 1 has a strong channel from that antenna AND a
`comparatively weak channel from antenna 2. A user on antenna 2 is selected in the same manner. This will keep the
`cross interference experienced by each user low. The power distribution across the two antennas can be performed in a
`number of ways, but one useful method is to split the total cell power equally across the two antennas (in a manner
`similar to STTD or CLTD Mode 1). This will simplify the amplifier design for each antenna.
`
`4
`
`Conclusion
`
`In this contribution, we showed that code limitation could substantially constrain the tj~roughputs achieved in HSDPA.
`We also suggested that code reuse can alleviate this problem. We saggest that RAN-1 further study the effect of code
`limitation in HSDPA and potential solutions to the problem using code reuse techniques.
`
`5
`
`References
`
`[1]
`
`[2]
`
`"DL structure in support for HS-PDSCH", R1-01-0478, Qualcomm.
`
`"Transmit diversity for HSDPA", R1-02-0530, Lucent.
`
`NK8681TC013089467
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1019-00003
`
`

`
`6
`
`Annex: Simulation parameters
`
`The system level simulation parameters are listed in Table 1 below.
`
`Parameter
`
`Cellular layout
`
`Table 1 Basic system level simulation assumptions.
`
`Explanation/Assumption
`
`Comments
`
`Hexagonal grid, 3-sector sites
`
`Provide your cell layout picture
`
`Site to Site distance
`
`2800 m
`
`Antenna pattern
`
`As proposed in [2]
`
`Only horizontal pattern specified
`
`Propagation model
`
`]~ 128.1 + 37.6 L, oglo(]~)
`
`R in kilometers
`
`CPICH power
`
`Other common channels
`
`-10 dB
`
`- 10 dB
`
`Power allocated to HSDPA Max. 70 % of total cell power
`transmission, including associated
`signaling
`
`Slow fading
`
`As modeled in UMTS 30.03, B 1.4.1.4
`
`Std. deviation of slow fading
`
`Correlation between sectors
`
`Correlation between sites
`
`8 dB
`
`1.0
`
`0.5
`
`Correlation distance of slow fading
`
`50 m
`
`Carrier frequency
`
`2000 MHz
`
`BS antenna gain
`
`UE antenna gain
`
`UE noise figure
`
`14 dB
`
`0 dBi
`
`9 dB
`
`Max. # of retransmissions
`
`Specify the value used
`
`Retransmissions by fast HARQ
`
`Fast HARQ scheme
`
`A21R
`
`BS total Tx power
`
`Up to 44 dBm
`
`Active set size
`
`Frame duration
`
`Scheduling
`
`3
`
`2.0 ms
`
`normalized Max C/I
`
`Specify Fast Fading model
`
`Jakes spectrum
`
`Maximum size
`
`Generated e.g. by Jakes or Filter
`approach
`
`The fundamentals of the data-traffic model are captured in Table 2 below.
`
`Table 2 Data-traffic model
`
`)arameters
`
`Process
`Packet Calls Size
`
`I
`
`Random Variable
`Pareto with cutoff
`
`I
`
`Time Between Packet Calls
`Packet Size
`
`Packets per Packet Call
`Packet Inter-arrival Time
`
`Geometric
`Segmented based on MTU
`size
`Deterministic
`Geometric
`
`Parameters
`A=I. 1, k=4.5 Kbytes, m=2 Mbytes, ~t = 25
`Kbytes
`~t = 5 seconds
`(e.g. 1500 octets)
`
`Based on Packet Call Size and Packet MTU
`~ = MTU size/peak link speed
`
`NK8681TC013089468
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1019-00004
`
`

`
`(open- loop)
`Packet Inter-arrival Time
`(elosed-loolz)
`
`Deterministic
`
`(e.g. [1500 octets * 8]/2 Mb/s = 6 ms)
`TCP/IP Slow Start
`(Fixed Network Delay of 100 ms)
`
`NK8681TC013089469
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1019-00005