An apparatus for converting source data to a channel-modulated signal having a plurality of pairs of in-phase (I) and quadrature-phase (Q) data in a mobile station, wherein the mobile station uses (N−1) data channels (N is an integer larger than two) and a control channel, the apparatus comprising: channel coding means for encoding the source data to generate (N−1) data parts and a control part, wherein the data parts are allocated to the data channels and the control part is allocated to the control channel; code generating means for generating spreading codes to be allocated to the channels, wherein each of the spreading codes is selected on the basis of a data rate of the data part and the control part and spreading codes are selected so that two consecutive pairs of the I and Q data are correspondent to two points located on the same point or symmetrical with respect to a zero point on a phase domain; and spreading means for spreading the control channel and the data channels by using the spreading codes to thereby generate the channel-modulated signal, wherein: the spreading codes correspond to an orthogonal variable spreading factor (OVSF) code, said channel coding means includes spreading factor generation means for generating a spreading factor related to the data rate of the data part, the spreading code allocated to the control channel is represented by C_256,0, where 256 denotes the spreading factor and 0 the code number, the spreading codes allocated to first and second data channels are represented by C_{4, 1}={1, 1, −1, −1}, said code generating means includes control means responsive to the spreading factor for generating code numbers for the channels, and spreading code generation means responsive to the spreading factor and the code number for generating the spreading code to be allocated to the channels, said spreading code generation means including, counting means for consecutively producing a count value in synchronization with a clock signal, first spreading code generation means responsive to the count value and the spreading factor for generating the spreading code to be allocated to the data channel, and second spreading code generation means responsive to the count value and the spreading factor for generating the spreading code to be allocated to the control channel, and the second spreading code generation means includes: second logical operation means responsive to the count value for carrying out a logical operation with the spreading factor and the code number related to the control part, to thereby generate the spreading code related to the control part; and second selection means for outputting the spreading code related to the control part in response to a select signal as the spreading factor related to the control part. view more

The apparatus as recited in claim 14, wherein the first spreading code generation means includes: first logical operation means responsive to the count value for carrying out a logical operation with the spreading factor and the code number related to the data part, to thereby generate the spreading code related to the data part; and first selection means for outputting the spreading code related to the data part in response to a select signal as the spreading factor related to the data part, and wherein said first logical operation means receives a code number of I₇I₆I₅I₄I₃I₂I₁I₀, a count value of B₇B₆B₅B₄B₃B₂B₁B₀ and a predetermined spreading factor. view more

The apparatus as recited in claim 15, wherein the first logical operation means carries out a logical operation of</claim-text> <maths id="MATH-US-00007" num="00007"><math r>∏i=0N-2⁢⁢Ii⊕·BN-1-i view more

The apparatus as recited in claim 14, wherein said second logical operation means receives a code number of I<sub>7</sub>I<sub>6</sub>I<sub>5</sub>I<sub>4</sub>I<sub>3</sub>I<sub>2</sub>I<sub>1</sub>I<sub>0</sub>, a count value of b>0 and a predetermined spreading factor. view more

The apparatus as recited in claim 17, wherein the second logical operation means carries out a logical operation of</claim-text> <maths id="MATH-US-00008" num="00008"><math r>∏i=0N-2⁢⁢Ii⊕·BN-1-i if the predetermined spreading factor is 2^N where N is 2 to 8. view more