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The device can be used for generating, in the framework of a CDMA communications terminal, both Walsh-Hadamard channeling codes and OVSF channeling codes. The device comprises a code generator preferably configured for generating Walsh-Hadamard codes. When the device is used for generating Walsh-Had

The device can be used for generating, in the framework of a CDMA communications terminal, both Walsh-Hadamard channeling codes and OVSF channeling codes. The device comprises a code generator preferably configured for generating Walsh-Hadamard codes. When the device is used for generating Walsh-Hadamard codes, the corresponding index values, applied to an input of the device, are sent to the input of the code generator. Generation of OVSF codes envisages, instead, that the corresponding indices, sent to an input of the device, undergo mapping, which enables generation, starting from the OVSF code, of the corresponding index identifying a string of symbols that is identical within the Walsh-Hadamard code. In this way each string of OVSF code symbols is generated, so producing, by means of the code generator, the generation of the identical string of symbols included in the Walsh-Hadamard code.

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1. A process for generating a first code having a set of strings of symbols, each string of symbols of said set having a given length and being identified by a given index, comprising the following operations:providing a generator capable of generating a second code comprising a corresponding set of

1. A process for generating a first code having a set of strings of symbols, each string of symbols of said set having a given length and being identified by a given index, comprising the following operations:providing a generator capable of generating a second code comprising a corresponding set of respective strings of symbols; the respective strings of symbols of said second code being each identical to a string of symbols of said first code and being identified by a respective corresponding index of said second code; determining, for the given index identifying each string of symbols of said first code, a respective corresponding index identifying the identical string of said second code; and generating each string of symbols of said first code starting from the respective given index, generating, by means of said generator, the identical string of said second code; said generator generating said identical string according to the respective corresponding index determined starting from said respective given index. 2. The process of claim 1, wherein said first code and said second code are codes with characteristics of orthogonality.3. The process of claim 2, wherein said first code and said second code are channeling codes for CDMA transmissions.4. The process of claim 1, wherein said first code and said second code are chosen in the group made up of the Walsh-Hadamard codes and the OVSF codes.5. The process of claim 4, wherein said first code is an OVSF code and said second code is a Walsh-Hadamard code.6. The process of claim 1 comprising the operation of creating a correspondence table between the given indices identifying the strings of symbols of said first code and the corresponding indices identifying the identical strings of symbols of said second code.7. The process of claim 4 wherein the given indices of said Walsh-Hadamard code are determined starting from the given indices of said OVSF code according to the relation where: 1 is a column vector of i elements equal to 1; L is the given length of the strings of the code symbols; M(i) is a vector that groups together the mapping values of the indices corresponding to a given length of the OVSF code; and the OVSF index represents the row position within the vector. 8. The process of claim 4 wherein the indices of said Walsh-Hadamard code are determined starting from said OVSF code through the following operations:expressing the OVSF index as a binary number; inverting the order of the bits of said binary number; subjecting the inverted binary number obtained from the inversion of the order of the bits to a right-hand shift with reset of n positions, where n is identified by the following relation: n=A?log2L where L denotes the length of the code strings, and A is the number of bits necessary for representing the maximum length of code to be generated, the further binary number obtained by means of said right-hand shift expressing the corresponding index of the Walsh-Hadamard code. 9. A device for generating a first code comprising a set of strings of symbols, each string of symbols of said set having a given length and being identified by a given index, the device comprising:a code generator for generating a second code comprising a corresponding set of respective strings of symbols; the respective strings of symbols of said second code being each identical to a string of symbols of said first code and being identified by a respective corresponding index of said second code; and a mapping circuit for determining, for the given index identifying each string of symbols of said first code, the respective corresponding index identifying the identical string of said second code; the device generating each string of symbols of said first code starting from the respective given index, generating, by means of said code generator, the identical string of said second code according to the corresponding index determined starting from said given index by means of said mapping circuit. 10. The device of claim 9 wherein said first code and said second code are codes with characteristics of orthogonality.11. The device according to claim 10 wherein said first code and said second code are channeling codes for CDMA transmissions.12. The device of claim 9 wherein said first code and said second code are chosen in the group made up of the Walsh-Hadamard codes and the OVSF codes.13. The device of claim 12 wherein said code generator is a Walsh-Hadamard code generator and said mapping circuit is configured to determine, starting from each given index that identifies a string of symbols of an OVSF code, the respective corresponding index that identifies the identical string of symbols in a Walsh-Hadamard code.14. The device of claim 9 wherein said mapping circuit comprises a memory element in which there is stored a table of correspondence between the given indices of said first code and the respective corresponding indices of said second code.15. The device of claim 12 wherein said mapping circuit comprises a computation module for determining the indices identifying the strings of symbols of said Walsh-Hadamard code starting from the given indices of said OVSF code according to the relation where: 1 is a column vector of i elements equal to 1; L is the given length of the strings of the code symbols; M(i) is a vector that groups together the mapping values of the indices corresponding to a given length of the OVSF code; and the OVSF index represents the row position within the vector. 16. The device of claim 12 wherein said mapping circuit comprises:a first module for storing the indices that identify the strings of symbols of said OVSF code as a binary number; an inversion and shift module for subjecting to inversion of the order of bits said binary number, then subjecting the inverted binary number thus obtained to a right-hand shift with reset of n positions, the further binary number obtained by means of said shift expressing in binary form the respective corresponding index identifying the identical bit string in said Walsh-Hadamard code; and a further computation module for determining the value n of the positions involved in said right-hand shift with reset starting from the relation n=A?log2L where L denotes the length of the code strings, and A is the number of bits necessary for representing the maximum length of the code to be generated. 17. The device of claim 9 comprising a selector capable of activating said code generator alternatively in a first operating condition and in a second operating condition, in which said code generator respectively generates:the strings of symbols of said second code starting from the respective corresponding indices that identify the strings of symbols of said another code; and the strings of symbols of said first code in the form of strings identical to said second code; said identical strings being generated using the corresponding indices determined by said mapping circuit starting from the given indices identifying the strings of said first code. 18. The device of claim 9 wherein said device is integrated in a single block for generating the codes with a scrambling code generator in a terminal for CDMA communications.19. The device of claim 9 comprising a terminal for CDMA communications, the device configured for co-operating both with receiving chain and with a transmission chain of said terminal.20. The device of claim 19, configured for co-operating both with correlators included in the receiving chain of the terminal and with spreading modules included in the transmission chain of the terminal.21. A process for generating codes used in CDMA communications, comprising:receiving a signal indicative of a length of code to be generated, an OVSF index signal, a Walsh-Hadamard index signal, and a selection signal; mapping the OVSF index signal into a corresponding Walsh-Hadamard index signal using a look-up table; selecting one of the Walsh-Hadamard index signal and the corresponding Walsh-Hadamard index signal in response to the selection signal; and generating the Walsh-Hadamard code corresponding to the selected index signal. 22. A process for generating codes used in CDMA communications, comprising:receiving a signal indicative of a length of code to be generated, an OVSF index signal, a Walsh-Hadamard index signal, and a selection signal; mapping the OVSF index signal into a corresponding Walsh-Hadamard index signal by applying the following relation: where: 1 is a column vector of i elements equal to 1; L is the given length of the strings of the code symbols; M(i) is a vector that groups together the mapping values of the indices corresponding to a given length of the OVSF code; and the OVSF index represents the row position within the vector; selecting one of the Walsh-Hadamard index signal and the corresponding Walsh-Hadamard index signal in response to the selection signal; and generating the Walsh-Hadamard code corresponding to the selected index signal. 23. A process for generating codes used in CDMA communications, comprising:receiving a signal indicative of a length of code to be generated, an OVSF index signal, a Walsh-Hadamard index signal, and a selection signal; mapping the OVSF through the following operations: expressing the OVSF index signal as a binary signal; inverting the order of bits in the binary signal; and subjecting the inverted binary signal obtained from the inversion of the order of the bits to a right-hand shift with reset of n positions, where n is identified by the following relation: n=A?log2L; where L denotes the length of the code strings, and A is the number of bits necessary for representing the maximum length of code to be generated, the further binary number obtained by means of said right-hand shift expressing the corresponding index of the Walsh-Hadamard code; selecting one of the Walsh-Hadamard index signal and the corresponding Walsh-Hadamard index signal corresponding to the selection signal; and generating the Walsh-Hadamard code corresponding to the selected index signal. 24. A device for generating codes used in CDMA communications, comprising:a first input for receiving a signal indicative of the length of code to generate, a second input to receive an OVSF index signal, a third input to receive a Walsh-Hadamard index signal, and a fourth input to receive a selection signal; a mapping circuit configured to receive the OVSF index signal and to map the OVSF index signal into a corresponding Walsh-Hadamard index signal by using a look-up table; a selection circuit configured to receive the Walsh-Hadamard index signal from the third input, and the corresponding Walsh-Hadamard index signal from the mapping circuit, and the selection signal from the fourth input, and further configured to output one of either the Walsh-Hadamard index signal and the corresponding Walsh-Hadamard index signal in response to the selection signal; and a generator configured to receive from the first input the signal indicative of the length of code to generate, to receive the selected one of the Walsh-Hadamard index signal and the corresponding Walsh-Hadamard index signal from the selection circuit, and to generate the Walsh-Hadamard code corresponding to the selected index signal. 25. A device for generating codes used in CDMA communications, comprising:a first input for receiving a signal indicative of the length of code to generate, a second input to receive an OVSF index signal, a third input to receive a Walsh-Hadamard index signal, and a fourth input to receive a selection signal; a mapping circuit configured to receive the OVSF index signal and to map the OVSF index signal into a corresponding Walsh-Hadamard index signal according to the relation: where: 1 is a column vector of i elements equal to 1; L is the given length of the strings of the code symbols; M(i) is a vector that groups together the mapping values of the indices corresponding to a given length of the OVSF code; and the OVSF index represents the row position within the vector; a selection circuit configured to receive the Walsh-Hadamard index signal from the third input, and the corresponding Walsh-Hadamard index signal from the mapping circuit, and the selection signal from the fourth input, and further configured to output one of either the Walsh-Hadamard index signal and the corresponding Walsh-Hadamard index signal in response to the selection signal; and a generator configured to receive from the first input the signal indicative of the length of code to generate, to receive the selected one of the Walsh-Hadamard index signal and the corresponding Walsh-Hadamard index signal from the selection circuit, and to generate the Walsh-Hadamard code in response thereto. 26. A device for generating codes used in CDMA communications, comprising:a first input for receiving a signal indicative of the length of code to generate, a second input to receive an OVSF index signal, a third input to receive a Walsh-Hadamard index signal, and a fourth input to receive a selection signal; a mapping circuit configured to receive the OVSF index signal and to map the OVSF index signal into a corresponding Walsh-Hadamard index signal in accordance with the following operations: expressing the OVSF index as a binary number; inverting the order of the bits of said binary number; subjecting the inverted binary number obtained from the inversion of the order of the bits to a right-hand shift with reset of n positions, where n is identified by the following relation: n=A?log2L where L denotes the length of the code strings, and A is the number of bits necessary for representing the maximum length of code to be generated, the further binary number obtained by means of said right-hand shift expressing the corresponding index of the Walsh-Hadamard code; a selection circuit configured to receive the Walsh-Hadamard index signal from the third input, and the corresponding Walsh-Hadamard index signal from the mapping circuit, and the selection signal from the fourth input, and further configured to output one of either the Walsh-Hadamard index signal and the corresponding Walsh-Hadamard index signal in response to the selection signal; and a generator configured to receive from the first input the signal indicative of the length of code to generate and the selected one of the Walsh-Hadamard index signal and the corresponding Walsh-Hadamard index signal from the selection circuit and to generate the Walsh-Hadamard code that corresponds to the selected index signal.