Nokia Networks Oy

Veli E Lipponen

Pentti Moilanen

The invention relates to method and code generator for updating linear feedback shift register (LFSR). The method comprises defining jumps corresponding to different powers of two for shifting from known state to new state. Then in each jump the LFSR obtained as a result of the jump in question is generated: the value of one element of the obtained LFSR is generated from the previous state and the pre-stored mask register corresponding to said obtained element, while the mask register determines the elements of the LFSR of the previous state, using which elements said element value is generated, and the generation of the value of one LFSR element is repeated for each remaining obtained feedback LFSR by shifting the mask register to the position of said remaining element and by generating the value of said remaining element of the obtained LFSR from the previous state and the shifted mask register.

Method for updating linear feedback shift register of code generator

The invention relates to a method and a generator for generating a short orthogonal spreading code in CDMA radio system. The method includes obtaining control data the length, the running number and the code class of the spreading code. A spreading code is formed such that the running number of the spreading code in the code class is first denoted by a binary code number of the same length as the code class. Thereafter, a modified code number is formed by reversing the code number. The following operations are repeated for each chip Of the spreading code: the running number of the chip is denoted by a binary chip number of the same length as the code class, and a binary sum is formed with an AND operation between the modified code number and the chip number, and one value is formed for the chip of the spreading code with an XOR operation between all the bits of the binary sum.

Growing community of inventors

Tampere, Finland

Veli E Lipponen