Generation of user equipment identification specific scrambling code for the high speed shared control channel

(54) Title: SPECIFIC MIXED CODE GENERATION TO IDENTIFY USER EQUIPMENT FOR SHARED HIGH SPEED CONTROL CHANNEL (30) Unionist Priority: 05/07/2002 us 60 / 378,509; 05/13/2002 US 60 / 378,170; 07/01/2002 US 10 / 187,640 (71) Depositor (s): Interdigital Technology Corporation. (US) (72) Inventor (s): Stephen G. Dick, Nader Bolourchi, Sung-Hyuk Shin (74) Attorney: Advocacy Pietro Ariboni S / C (86) International Request: pct US03 / 14205 of 05/05/2003 (87) International Publication: wo 09/096694 of 11/20 / 2003 (57) Summary: GENERATION OF SPECIFIC MIXED CODE OF IDENTIFICATION OF USER EQUIPMENT FOR SHARED HIGH SPEED CONTROL CHANNEL. A code is produced for use in mixed or unmixed data associated with a shared high-speed control channel (HS-SSCH) for a particular user device. A user identification of the particular user equipment comprises L bits. A 1/2 rate convolutional encoder (14) processes at least the user identification bits by a 1/2 rate convolutional code to produce the code.

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Generation of specific mixed code to identify user equipment for shared high-speed control channel.

The present invention relates to wireless communication systems. More particularly, the present invention relates to specific mixed sequences for identifying user equipment for shared high-speed control channels (HS-SCCH).

Background

A high-speed downlink access package (HSDPA) is proposed for multiple access systems by broadband code division. HSDPA allows high data downlink rates to support multimedia services.

To support HSDPA, high-speed shared channel controls (HS-SCCHs) are used. HS-SCCHs are used for the vital information control signal for user equipment (UEs). Each HS-SCCH has two parts, referred to as Part-1 and Part-2. Part-1 contains critical time information required for the UE. This information includes the channel code parameter and the type of modulation used by the high-speed downlink physical shared channel control (HS-PDSCH) which carries the HSDPA payload. This information is vital to support HSDPA, since HSDPA uses adaptive modulation and modulation (AMC).

To obtain information from Part-1, each EU HSDPA monitors up to four HS-SCCHs for its information. The information for the particular UE is distinguished from other UEs by their UE identification (UE ID) specifying a mixing sequence. The UE processes each monitored HS-SCCH with its mixed sequence specific UE ID to detect the intended HS-SCCH for the UE. Once processed, the UE determines which HS-SCHH, if any, the information was obtained using its mixed strings. The UE does not mix the data obtained in Part-1 of its HS-SCCH using its mixed sequence.

Until recently, a 10-bit UE ID was used as the basis for the UE ID-specific mixed strings. In this case, this UE ID has been converted into a mixed 40 bit string. By changing the 10-bit UE ID into a 40-bit UE ID for specific mixed sequence, the 10-bit UE ID is processed by a Reed-Muller block to produce a 32-bit code. The first 8 bits of the produced code are repeated and added to the end of the 32-bit code to produce a 40-bit code.

Despite being proposed to extend the size of the UE ID to 16 chips, the current proposal for HS-SCCHs uses a 10-bit UE ID. This UE ID is converted into a mixed 40 bit string. To change the 10-bit UE ID in one • · · ·· ···· · · ····

2/3 40-bit mixing sequence, the 10-bit UE ID is processed in a Reed-Muller block to produce a 32-bit code. The first 8 bits of the produced code are repeated and added to the end of the 32-bit code to produce a 40-bit code.

To reduce the occurrence of false detections, it is desirable to have a good separation between the mixed codes produced for each UE ID. Accordingly, it is desirable to have alternative accesses to produce mixed codes.

abstract

A code is produced to use associated data mixed or demixed with high-speed shared channel controls (HS-SCCHs) for a particular user device. A user identification for a particular user device comprises L Bits. A convolutional encoder of¹Λ rate processes at least the user identification bits by a convolutional code of ¹Z fee to produce the code.

Brief Description of Drawings

- Figure 1 is a preferred diagram of a circuit to produce a code associated with a particular user for an HS-SCCH.

- Figure 1B is a diagram of a rate matching block used in conjunction with figure 1 A;

- Figure 2A is a preferred circuit diagram for producing a code associated with a 16-bit user ID;

Figure 2B is a diagram of a rate matching block used in conjunction with figure 1A;

- Figure 3 is a simplified user equipment using the specific mixing code of the UE ID; and

- Figure 4 is a simplified base station using the UE ID specific mixing code.

Detailed Description of Preferred Achievements

Although the preferred configurations are described together with a preferred application of the invention for use with HSDPA of the third generation partnership project (3GPP) of multiple access code systems for broadband code division (W-CDMA), the The invention can be applied to other code division multiple access communication systems. Figures 1A and 1B are preferred diagrams of UE ID specific mixing sequence circuits. A UE ID Xue, size L is inserted into the circuit. L can be any size, such as 8 bits, 10 bits, 16 bits, etc. The UE ID = {Xuei. Xuel} is inserted into a rate convolutional encoder as shown in figure 1A. Along the UE ID, extra bits, such as zeros, can be added to the end of the

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3/3 input string to extend the length of the input string and, accordingly, the output string. The use of the convolutional encoder of¹/ z rate 10 provides a high level of code separation between the output strings produced by different UE IDs. In addition, the current 3GPP WCDMA communication systems proposed use a rate 10 convolutional encoder for a forward error correction (FEC) technique. Accordingly, no additional hardware is required to generate the specific mixing sequence of the encoded convolutional UE ID. After encoding, based on the size of the output string, a rate matching stage 12 can be added to eliminate bits to obtain a desired string size.

Figures 2A and 2B are circuit diagrams of preferred EU ID specific mixing sequence for a preferred EU ID code of size 16, L = 16. The 16-bit UE ID, {Xuei. · Xuel}&gt; is an entry in a% rate 14 convolutional encoder along with eight zero bits added at the end of the input string. As a result, the input string is Xuei, · Xuw, 0, 0, 0, 0, 0, 0, 0, 0. After being processed by Vi rate 14 convolutional encoder, the input code is 48 bits long, CU = {Cuei, ·· Cuel} ·

To reduce the code size to a preferred size of 40 bits, eight bits are preferably eliminated. Figure 2B illustrates the rate 16 encounter stage for doing the elimination. After the rate 16 encounter stage, the effective size of the mix code is 40 bits.

Figure 3 is a simplified diagram of a user's equipment for demixing an HS-SCCH using the specific mixing code of the UE ID. The mixing code of the UE ID is mixed, such as exclusive-or gate 18, with the HS-SCCH received for use in retrieving the HS-SCCH encoded data.

Figure 4 is a simplified diagram of a base station encoded with mixing data with UE ID using the specific mixing code for transfer over the HS-SCCH. The encrypted data is mixed with the mixed code of the UE ID, such as an exclusive-or 20 gate, for a particular user. The mixed data is used to produce the HS-SCCH for transfers to the particular user.

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