KR20040103731A - Apparatus for generating ovsf code for uplink data spreading in umts - Google Patents

Abstract

PURPOSE: An orthogonal code generator for uplink data spreading in an asynchronous W-CDMA system is provided to replace an old technique without using a plurality of logic circuits and without a big change in hardware size by using a simple logic circuit or a small capacity memory. CONSTITUTION: A storage part(20) stores 16x16 Walsh codes. The second exclusive OR unit(30) executes exclusive OR operation for a signal outputted from the storage part(20) and the 16th Walsh code outputted from the storage part(20) or an additional register(21) and generates an orthogonal code for the spreading of a PRACH(Physical Random Access CHannel) control part. The first generator(41) repeatedly generates '0011' for the spreading of a DPDCH(Dedicated Physical Data CHannel) and a PCPCH(Physical Common Packet CHannel) message data part. The second generator(42) generates '0' for the spreading of a DPCCH(Dedicated Physical Control Data CHannel) and a PCPCH message control part. Multiplexers(51,52) select and output one among the codes for channel spreading according to a control signal inputted from a control part. The control part outputs channel information and an OVSF(Orthogonal Variable Spreading Factor) ID, and controls an address controller(10) in order to output data, stored in the storage part(20), according to the OVSF ID.

Description

Orthogonal Code Generation Apparatus for Reverse Data Spread of Asynchronous Broadband Code Division Multiple Access System {APPARATUS FOR GENERATING OVSF CODE FOR UPLINK DATA SPREADING IN UMTS}

The present invention relates to an apparatus for generating orthogonal codes for reverse data spreading in a third generation asynchronous mobile communication system, and to a device for generating codes for reverse spreading without using a general logic circuit.

The orthogonal code allocation method proposed in the 3rd generation asynchronous mobile communication standard is as follows.

The reverse channels of the 3rd generation asynchronous mobile communication system include a Dedicated Physical Control Channel (DPCCH), a Dedicated Physical Data Channel (DPDCH), a Physical Random Access Channel (PRACH), and a PCPCH ( Physical Common Packet Channel).

Orthogonal Variable Spreading Factor (OVSF) numbers for spreading are allocated to the DPCCH and DPDCH, which are control channels and data channels in the reverse direction, as follows.

The DPCCH is always spread by Code 0 of the Spreading Factor (SF) 256, c _c = C _{Ch, 256,0} .

When only one DPDCH is transmitted _, spread by code c _{d, 1} = C _{Ch, SF, k, where} SF is the spreading factor of DPDCH1 and k = SF / 4.

When two or more DPDCHs are transmitted, all DPDCHs use spreading factor 4, and DPDCHn is spread by code c _{d, n} = C _{ch, 4, k} . In this case, k = 1 when n∈ {1,2}, k = 3 when n∈ {3,4}, and k = 2 when n∈ {5,6}.

Meanwhile, an OVSF code number is allocated to a message part of a physical random access channel (PRACH) for requesting access by the following method.

When the preamble signature is s (0≤s≤15), the control part is always spread by code m of SF 256, C _c = C _{ch, 256, m} . Where m = 16 × s + 15. The data part is spread by c _d = C _{ch, SF, m} . here Where SF = 32, 64, 128, 256.

The message part of PCPCH is similar to DPDCH. The control part is always spread by code 0, c _c = C _{Ch, 256,0} of SF (Spreading Factor) 256, and the data part is c _d = C _{Ch, It} is diffused by _{SF, k} . SF is the spreading factor of PCPCH and k = SF / 4. The spreading factor is 4 to 256.

1 is a hardware structure of a commonly used orthogonal code generator. In this structure, as shown in FIG. 4, since the OVSF code has a correlation in the same form as the inverted Walsh code, only the code address is adjusted to generate the OVSF code using a conventional orthogonal code generator.

However, this method requires a large number of logic circuits, and there are problems such as consultation with the patent holder in actual use.

SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide an orthogonal code generation apparatus for reverse data spreading in an asynchronous broadband code division multiple access system that can replace the conventional technology without a large change in hardware size.

1 is a hardware configuration diagram of a conventional quadrature code generator.

2 is a block diagram of an orthogonal code generation apparatus using a memory according to a first embodiment of the present invention.

3 is a diagram illustrating a relationship between an orthogonal variable spreading coefficient ID and a Walsh ID for spreading a message data part of a reverse random access channel.

4 is a diagram illustrating a relationship between a message control part orthogonal variable spreading coefficient ID and Walsh ID of a reverse random access channel.

5 is a diagram illustrating a 16 × 16 orthogonal variable diffusion coefficient.

6 is a block diagram of an apparatus according to a second embodiment of the present invention.

The present invention relates to a code generation device for reverse data spreading in an asynchronous broadband code division multiple access system, comprising: a storage unit having a Walsh code of 16X16, a signal output from the storage unit, and a signal output from the storage unit A second exclusive logic amalgamator exclusively combines a 16th Walsh code and a Walsh code having a period of 16 outputted from the storage unit are repeated 256 times to generate a preamble of a reverse random access channel or a reverse random sequence through the exclusive logical sum. Generating a code for spreading a message control part of an access channel or generating a code for spreading a message data part of a reverse random access channel by repeating a Walsh code having a period of 16 output from the storage unit; It features.

2 is a block diagram of an orthogonal code generation apparatus using a memory according to a first embodiment of the present invention, and FIG. 3 is a relation between an orthogonal variable spreading coefficient ID and Walsh ID for spreading a message data part of a reverse random access channel. 4 is a diagram illustrating a relationship between a message control part orthogonal variable spreading coefficient ID and Walsh ID of a reverse random access channel, FIG. 5 is a view showing a 16X16 orthogonal variable spreading coefficient, and FIG. A block diagram of the apparatus according to the second embodiment of the present invention.

Hereinafter, the present invention will be described with reference to the accompanying drawings.

An apparatus for generating orthogonal variable spreading coefficients according to the present invention generates an Orthogonal Variable Spreading Factor (OVSF) code that provides orthogonality between different physical channels.

In general, OVSF code sets and Walsh code sets of the same spreading factor correspond to one-to-one. The correspondence relationship is as follows. Spreading factor (Spreading factor) is 2 ^k times, where n (0≤n≤2 ^k -1) orthogonal variable spreading factor (OVSF) code C _{OVSF a, k, n} is a binary (binary) representing the value of n when called As follows.

Likewise, when m times (0 ≦ m ≦ 2 ^k −1) orthogonal variable diffusion coefficient (OVSF) codes having a spreading factor of 2 ^k are C _{Walsh, k, m} , the following is true.

The present invention is implemented in a simpler structure compared to the OVSF code generator having a general structure by using the above property and the OVSF code allocation rule of the physical channel in the reverse direction (UL).

First, a reverse random access channel (PRACH), which is one of the reverse (UL) physical channels, is as follows.

The reverse random access channel is a reverse random access channel message part consisting of a preamble part transmitted from the terminal to the base station and a reverse random access channel message data part and a reverse random access channel message control part with respect to the response signal (AICH) of another base station. It is composed.

(1) Reverse Random Access Channel Preamble

The preamble of the reverse random access channel (RACH) is the same as repeating the Walsh code of SF 16. Therefore, in the preamble transmission of the reverse random access channel (PRACH), C _{walsh, 4, s} is selected as the output of the OVSF code generator. If a preamble signature, s is passed, one of 16 codes will be output depending on the value of the signature.

(2) Reverse random access channel message part (PRACH message part)

SF of the reverse random access channel message data part (PRACH message data part) 2 ^k (k = 5, 6, 7, 8), OVSF code number, m _data is as follows.

In the above equation, the binary representation of m _data is the four-bit binary representation of s (s ₃ × 2 ³ + s ₂ × 2 ² + s ₁ × 2 + s ₀ ). It can be seen that the value is left-shifted by -4) bit (see FIG. 3).

Accordingly, an equivalent Walsh code number corresponding to m _data can be represented by 4 bits and is uniquely determined according to preamble signatures, regardless of SF, that is, k.

If the equivalent Walsh code number of the reverse random access channel message data part for s is W (s), W (s) can be expressed as follows.

Walsh codes with period 2 ^k (k = 5,6,7,8) and number W (s) (W (s) = 0,1, ... 15) have period 16 and number W (s) Since the Walsh code is repeated, the following holds true.

Where i is the time index. In conclusion, all orthogonal variable spreading coefficient codes for the reverse random access channel message data part can be generated from 16 Walsh code sets having a period of 16.

The SF of the reverse random access channel message control part is always 256, and the OVSF code number for the preamble signature, s, and m _ctrl are as follows.

The binary representation of m _ctrl shifts the 4-bit binary representation of s (s ₃ × 2 ³ + s ₂ × 2 ² + s ₁ × 2 + s ₀ ) to the left by four bits, and shifts the lower four bits to one. (See Figure 4).

Therefore, the equivalent Walsh code number corresponding to m _ctrl has a value of 240 to 255 and a relationship of 240 + W (s) is established for s. A Walsh code with period 256 and number 240 + W (s) (W (s) = 0,1, · 15) is a modulated repetition of Walsh code with period 16 and number W (s). The following holds true.

here " Means "exclusive OR." As a result, all orthogonal variance coefficients for the reverse random access channel message control part, as with the reverse random access channel message data part, are generated from 16 Walsh codes of 16 periods. Can be.

The above is summarized in the following table (Table 1: Equivalent Walsh code number for PRACH message data part) (Table 2: Equivalent Walsh code number for PRACH message control part).

TABLE 1

TABLE 2

Next, the DPCH (Dedicated Physical Channel) channel composed of one of the reverse physical channels (DPDCH: Dedicated Physical Data Channel) and the reverse control channel (DPCCH) are as follows.

(3) Dedicated Physical Data Channel (DPDCH)

SF of the reverse data channel (DPDCH) may have a value of 2 ^k (k = 2,3,4,5,6,7,8). At this time, the OVSF code number is determined to be SF / 4 (= 2 ^k-2 ). Therefore, using the above correspondence can be expressed as follows.

That is, the reverse data channel is always spread twice with the Walsh code regardless of SF. The Walsh code 2 is a pattern in which the "0011" pattern is repeated repeatedly, so that a code can be generated using a clock, a delay, or a register without any complicated hardware (H / W).

(4) Dedicated Physical Control Channel (DPCCH)

In case of DPCCH, SF is always 256 and OVSF code number is 0, so the following is true.

Walsh code 0 is a form of "0" that is repeated over and over again, so no complicated hardware is required.

Next, a look at the reverse packet channel (PCPCH: Physical Commom Packet Channel) first.

(5) PCPCH message part (PCH) (Physical Common Packet Channel)

The PCPCH message data part may have a value of 2 ^k (k = 2,3,4,5,6,7,8) in the same way as the reverse data channel. At this time, the OVSF code number is determined as SF / 4 (= 2 ^k-2 ). Therefore, using the above correspondence can be expressed as follows.

That is, the reverse packet channel always spreads to the Walsh code twice regardless of SF. The Walsh code 2 is a pattern in which the "0011" pattern is repeated repeatedly, so that a code can be generated using a clock, a delay, or a register without any complicated hardware (H / W).

In the case of the PCPCH message part, the SF is always 256 and the OVSF code number is 0, similarly to the backward control channel.

The above is summarized in Table 3 (Table 3: Equivalent Walsh code number for DPDCH, DPCCH & PCPCH).

TABLE 3

As described above, it is possible to store the spreading factor 16 walsh code (16 × 16 Walsh code) in memory and generate orthogonal codes for all the spreading factors without satisfying the recommendations of standardization. . Even in multi-code support, 16 walsh codes can be generated using simple control signals.

As described above in "(1)" to "(5)", each reverse channel can be generated by a 16x16 Walsh code, which will be described with reference to FIG. Is as follows.

In the storage unit 20 of FIG. 2, Walsh codes (see FIG. 5) of 16 × 16 are stored, and the second exclusive logic unit 30 stores the signals output from the storage unit 20 and the storage unit 21 (30). Exclusive logic sum of the 16th Walsh code output from)) generates an orthogonal code for spreading the random access channel message control part. Meanwhile, the 16th Walsh code may be provided by using a separate 16-bit register 21 or the separate memory 21 may be used to generate the 16th Walsh code.

The first generator 41 repeatedly generates " 0011 " to spread the reverse data channel and the reverse packet channel message data part, and the second generator 42 spreads the reverse control channel and the reverse direction packet channel message control part. Generates "0" for this purpose.

The mux 51 and 52 select one of the codes for spreading the respective channels according to the control signal of the controller and output the I and Q signals. The mux 51 and 52 select and output the input signal according to the channel information.

The controller (not shown) outputs an orthogonal variable diffusion coefficient ID (OVSF ID) according to the channel information and the channel information, and an address controller to output data stored in the storage unit 20 according to the orthogonal variable diffusion coefficient ID. To control (10).

That is, the controller generates a preamble of the reverse random access channel by repeating the Walsh code having a period of 16 outputted from the storage 20 in accordance with the signature s 256 times, or through the exclusive logical combiner 30, and reverse reverse access channel. Generate code for spreading message control part of. In addition, the control unit generates a code for spreading the message data part of the reverse random access channel by repeating the Walsh code having a period of 16 output from the storage unit 20 and through the first and second generators 41 and 42. Generates a code for spreading the reverse data channel, reverse control channel, and reverse packet channel message parts.

As described above in "(1)" to "(5)", each reverse channel can be generated by a Walsh code of 16x16, which will be described with reference to FIG. Is as follows.

Compared to the first embodiment of FIG. 2, the second embodiment of FIG. 6 has a storage unit 20 having an ID converter 11, a Walsia ID generator 100, an offset counter 200, four logical multipliers ( 300), the first exclusive logic combiner (400).

The Walsia ID generator 100 outputs a 4-bit Walsh ID based on the corresponding Walsh ID information according to the idea of the orthogonal variable diffusion coefficient. At this time, the input information is output from the ID converter 11, the ID converter 11 outputs the corresponding Walsh ID according to the orthogonal variable diffusion coefficient output from the control unit.

The four logical multipliers 300 logically multiply the respective values output from the Walsia ID generator 100 and the 4-bit offset counter 200.

The first exclusive logical combiner 400 receives all the output values from four logical multipliers and outputs an exclusive logical sum to generate a code for spreading a preamble of a reverse random access channel and a message data part of a reverse random access channel. do.

The register 21 stores information of the 16th Walsh code among the 16x16 Walsh codes in order to generate a code for spreading the message control part of the reverse random access channel.

The second exclusive logic unit 30 performs an exclusive logic sum between the value output from the first exclusive logic unit 400 and the 16x16 Walsh code output from the register 21 to control the message control part of the reverse random access channel. Generate code for spreading.

The first generator 41 repeatedly generates 0011 to spread the reverse data channel and the reverse packet channel, and may be implemented by a 4-bit register.

The second generator 42 generates "0" for the spread of the reverse control channel.

The first mux 51 selects and outputs any one of the codes for channel spreading from the first exclusive logic combiner 400 and the first generator 41 according to the channel information of the controller.

The second mux 52 selects and outputs any one of codes for channel spreading from the second exclusive logic combiner 30 and the second generator 42.

The control unit (not shown) spreads the preamble of the reverse random access channel and the message data parts of the reverse random access channel by the logical product of the Walsh-ID generator 100 and the offset counter 200 and the first exclusive logical combiner 400. And generates a code for spreading the message control part of the reverse random access channel through the second exclusive logical combiner (30). In addition, the control unit generates a code for spreading the reverse data channel and the reverse packet channel message data part through the first generator 41, and generates the reverse control channel and the second control signal through the second generator 42.

Generates a code for spreading the reverse packet channel message control part. Then, the control unit provides the selection information according to the channel information to the mux 51, 52 to selectively output the code for each channel spread.

The above-described embodiments are intended to effectively explain the content of the present invention, but not to limit it. For example, it is obvious that the first generator 41 and the second generator 42 may be replaced by a register and a memory, and may also be generated using the storage unit 20 according to the selection of the storage unit 20. . Therefore, the protection scope of the present invention will be limited only by the appended claims, not the embodiment, and should be construed as including all the above-described modifications.

As described above, the present invention has the advantage that the conventional technology can be replaced by using a simple logic circuit or a small memory, without using a large number of logic circuits and without large change in hardware size.

Claims (13)

An apparatus for reverse channel spreading in an asynchronous wideband code division multiple access system, A storage unit storing 16x16 Walsh codes; And, The control unit repeats the Walsh code having a stored period of 16 in the storage unit to generate a code for spreading the preamble of the reverse random access channel and the message data part of the reverse random access channel. Orthogonal code generation apparatus for reverse data spreading in an asynchronous broadband code division multiple access system, characterized in that it comprises a. The method according to claim 1, And a second exclusive logic combiner for exclusively combining the signal output from the storage and the 16th Walsh code output from the storage to generate a code for spreading the message control part of the reverse random access channel. Orthogonal Code Generation Apparatus for Reverse Data Spread of Asynchronous Broadband Code Division Multiple Access Systems. The method according to claim 1 or 2, And a first generator for repeatedly generating 0011 for spreading the reverse data channel and the reverse packet channel. The method according to claim 3, And a second generator for generating " 0 " for spreading the reverse control channel. ≪ RTI ID = 0.0 > A < / RTI > apparatus for reverse data spreading in an asynchronous broadband code division multiple access system. The method according to claim 3, A first mux for selecting and outputting any one of codes for channel spreading output from the storage unit and the first generator according to a control signal of the controller; And A second mux for selecting and outputting any one of codes for channel spreading output from the second exclusive logic combiner and a second generator Orthogonal code generation apparatus for reverse data spreading in an asynchronous broadband code division multiple access system, characterized in that it comprises a. An apparatus for reverse channel spreading in an asynchronous wideband code division multiple access system, A storage unit storing 16x16 Walsh codes; An address controller for generating a specific address to generate a Walsh code stored in the storage; A second exclusive logic summation unit configured to perform an exclusive logical sum of the signal output from the storage unit and the 16th Walsh code output from the storage unit; A first generator for repeatedly generating 0011 for spreading the reverse data channel; A second generator generating “0” for spreading of the reverse control channel; A first mux for selecting and outputting any one of the storage unit and a code for channel spreading output from the first generator; A second mux for selecting and outputting any one of codes for channel spreading output from the second exclusive logic combiner and a second generator; And, Repeating Walsh codes having a period of 16 stored in the storage unit through the address generator to generate a code for spreading a preamble of a reverse random access channel and a message data part of a reverse random access channel, and reverse random through the exclusive logical sum Control unit for generating code for spreading message control part of access channel Orthogonal code generation apparatus for reverse data spreading in the asynchronous broadband code division multiple access system, characterized in that it comprises a. An apparatus for reverse channel spreading in an asynchronous wideband code division multiple access system, A Walsh ID generator for outputting a 4-bit Walsh ID by corresponding Walsh ID information according to an ID of an orthogonal variable diffusion coefficient; 4-bit offset counter; Four logical multipliers for logically multiplying the respective values output from the Walshidi generator and the offset counter; A first exclusive logic summ that receives all the values output from the logical multiplier and outputs an exclusive logic sum; A control unit configured to generate a code for spreading a preamble of the reverse random access channel and a message data part of the reverse random access channel by the walsid generator, the logical product of the offset counter, and the first exclusive logical summator Orthogonal code generation apparatus for reverse data spreading in an asynchronous broadband code division multiple access system, characterized in that it comprises a. The method according to claim 7, In order to generate a code for spreading the message control part of the backward random access channel, a second exclusive logic for performing an exclusive logic sum between the value output from the first exclusive logic and the 16th Walsh code among the 16x16 Walsh codes is performed. An orthogonal code generation device for reverse data spreading in an asynchronous broadband code division multiple access system, further comprising: a. The method according to claim 7 or 8, And a first generator for repeatedly generating 0011 for spreading the reverse data channel and the reverse packet channel. The orthogonal code generation apparatus of the reverse data spreading in the asynchronous wideband code division multiple access system. The method according to claim 9, And a second generator for generating " 0 " for spreading the reverse control channel. ≪ RTI ID = 0.0 > A < / RTI > apparatus for reverse data spreading in an asynchronous broadband code division multiple access system. The method according to claim 9, A first mux for selecting and outputting any one of the first exclusive logic combiner and a code for channel spreading output from the first generator according to a control signal of the controller; And A second mux for selecting and outputting any one of codes for channel spreading output from the second exclusive logic combiner and a second generator Orthogonal code generation apparatus for reverse data spreading in an asynchronous broadband code division multiple access system, characterized in that it comprises a. The method according to claim 9, A 16-bit register for generating a 16th Walsh code among the 16x16 Walsh codes; Generation of orthogonal code for reverse data spreading in the asynchronous broadband code division multiple access system, characterized in that the first generator for repeatedly generating 0011 for spreading the reverse data channel and the reverse packet channel has a 4-bit register. Device. An apparatus for reverse channel spreading in an asynchronous wideband code division multiple access system, A Walsh ID generator for outputting a 4-bit Walsh ID by corresponding Walsh ID information according to an ID of an orthogonal variable diffusion coefficient; 4-bit offset counter; Four logical multipliers for logically multiplying the respective values output from the Walshidi generator and the offset counter; A first exclusive logic summ that receives all the values output from the logical multiplier and outputs an exclusive logic sum; A second exclusive logic combiner performs an exclusive logic sum of a value output from the first exclusive logic combiner and a 16th Walsh code of a 16x16 Walsh code to generate a code for spreading a message control part of a reverse random access channel. ; A first generator for repeatedly generating 0011 to spread the reverse data channel and the reverse packet channel; A second generator generating “0” for spreading of the reverse control channel; A first mux for selecting and outputting any one of the first exclusive logic combiner and a code for channel spreading output from the first generator according to a control signal of the controller; A second mux for selecting and outputting any one of codes for channel spreading output from the second exclusive logic combiner and a second generator; A code for spreading the preamble of the reverse random access channel and the message data part of the reverse random access channel is generated by the logical product of the Walshidi generator, the offset counter, and the first exclusive logical summator, and the second exclusive logical summator is generated. Generate a code for spreading the message control part of the reverse random access channel through, generate a code for spreading the reverse data channel and reverse packet channel through the first generator, and spread the reverse control channel through the second generator Control to generate code for Orthogonal code generation apparatus for reverse data spreading in an asynchronous broadband code division multiple access system, characterized in that it comprises a.