Random access apparatus and method

1. A random access apparatus comprising:

a radio frequency (RF) transmitting/receiving unit configured to receive a preamble introduction broadcasting signal from a base station and to transmit a random access preamble to the base station;

an introduction broadcasting signal processing unit configured to extract a random access usage relating to M-sequences and hadamard sequences from the received preamble introduction broadcasting signal;

a selecting unit configured to select a plurality of M-sequences and a hadamard sequence corresponding to a random access purpose based on the extracted random access usage; and

a preamble generating unit configured to produce the random access preamble multiplying the selected plurality of M-sequences and the selected hadamard sequence,

wherein the preamble generating unit includes:

a first M-sequence generating unit configured to generate a first M-sequence having an initial value determined by a first identifier of the base station;

a second M-sequence generating unit configured to generate a second M-sequence having an initial value determined by a random number;

a hadamard sequence generating unit configured to generate a hadamard sequence which represents a kind of a random access service; and

a multiplying unit configured to generate the random access preamble by multiplying the first M-sequence, the second M-sequence and the hadamard sequence.

2. The random access apparatus as recited in claim 1 , wherein the second M-sequence generating unit generates the second M-sequence having the initial value determined by the random number and a second identifier of the base station.

3. The random access apparatus as recited in claim 1 , wherein, the hadamard sequence represents the kind of the random access service and a priority of the random access service is presented by using a persistence value.

4. The random access apparatus as recited in claim 3 , wherein a priority of the random access service is presented by using a random access code number contained in the plurality of M-sequences.

5. A random access method comprising the steps of:

receiving a preamble introduction broadcasting signal related to a random access usage from a base station;

selecting a plurality of M-sequences and a hadamard sequence corresponding to a random access purpose based on the random access usage and generating a random access preamble multiplying the selected M-sequences and the selected hadamard sequence;

transmitting the generated random access preamble to the base station; and

receiving a preamble response signal showing whether a random access is successful or not from the base station,

wherein, in the step of selecting, the random access preamble is generated with two selected M-sequences and the selected hadamard sequence corresponding to the random access purpose based on the random access usage, and

wherein an initial value of a first M-sequence of the two selected M-sequences is determined by a first identifier of the base station and an initial value of a second M-sequence is decided by a random number.

6. The random access method as recited in claim 5 , wherein the initial value of the second M-sequence is determined by a second identifier of the base station and the random number.

7. The random access method as recited in claim 5 , wherein, the hadamard sequence represents a kind of a random access service and a priority of the random access service is presented by using a persistence value.

8. The random access method as recited in claim 5 , wherein a priority of the random access service is presented by using a random access code number contained in the plurality of M-sequences.

9. The random access method as recited in claim 5 , further comprising the step of:

when the number of chips (symbols) of the random access preamble is larger than the number of chips (symbols) of the hadamard sequence, repeatedly transmitting the hadamard sequence to the base station in such a manner that a diversity gain of the hadamard sequence is larger than a predetermined value.

10. The random access method as recited in claim 5 , further comprising the step of:

when the number of chips (symbols) of the random access preamble is larger than the chip number of any one of the plurality of M-sequences, repeatedly transmitting a multiplying result which is obtained by multiplying the M-sequence having smaller number of chips and the hadamard sequence to the base station in such a manner that a diversity gain of the multiplying result is larger than a predetermined value.

11. A random access apparatus comprising:

a radio frequency (RF) transmitting/receiving means for receiving a preamble introduction broadcasting signal from a base station and transmitting a random access preamble to the base station;

an introduction broadcasting signal processing means for extracting a random access usage relating to M-sequences and hadamard sequences from the received preamble introduction broadcasting signal;

a selecting means for selecting a plurality of M-sequences and a hadamard sequence corresponding to a random access purpose based on the extracted random access usage; and

a preamble generating means for producing the random access preamble multiplying the selected plurality of M-sequences and the selected hadamard sequence,

wherein the preamble generating means includes:

a first M-sequence generating means for generating a first M-seguence having an initial value determined by a first identifier of the base station;

a second M-sequence generating means for generating a second M-sequence having an initial value determined by a random number;

a hadamard sequence generating means for generating a hadamard sequence which represents a kind of a random access service; and

a multiplying means for generating the random access preamble by multiplying the first M-sequence, the second M-sequence and the hadamard sequence.

12. The random access apparatus as recited in claim 11 , wherein the second M-sequence generating means generates the second M-sequence having the initial value determined by the random number and a second identifier of the base station.