Interleaving apparatus and method for symbol mapping in an HSDPA mobile communication system

A method for interleaving coded bits encoded at a prescribed code rate in a transmitter of a mobile communication system having a buffer comprised of a plurality of rows and columns, for writing the coded bits, the method comprising the steps of:

• separating the buffer into a first write area and a second write area according to a ratio of coded bits with higher priority among the coded bits to coded bits with lower priority;
• sequentially writing a stream of the coded bits with higher priority in a row direction from a first column to a last column among the columns in the first write area, and sequentially writing a stream of the coded bits with lower priority in a row direction from a first column to a last column among the columns in the second write area;
• permuting the columns in the buffer according to a given rule;
• dividing the rows in the buffer into a first read area and a second read area having equal size;
• permuting, between the first read area and the second read area, a number of rows equal to a number determined by a prescribed modulation technique among the rows of each of the first read area and the second read area;
• and
• sequentially reading the rows in the entire buffer in a column direction from a first row to a last row.

A method for interleaving coded bits encoded at a prescribed code rate in a transmitter of a mobile communication system having a buffer comprised of a plurality of rows and columns, for writing the coded bits, the method comprising the steps of:

• separating the buffer into a first write area and a second write area according to a ratio of coded bits with higher priority among the coded bits to coded bits with lower priority;
• sequentially writing a stream of the coded bits with higher priority in a row direction from a first column to a last column among the columns in the first write area, and writing a stream of the coded bits with lower priority in a row direction from a last column to a first column among the columns in the second write area in such a manner that the stream of coded bits is written in a reverse direction from a last row to a first row in the second write area;
• permuting the columns in the buffer according to a given rule;
• dividing the rows in the buffer into a first read area and a second read area having equal size;
• and
• alternately reading a number of bits equal to a number determined by a prescribed modulation technique from the first read area and the second read area in such a manner that the bits are sequentially read in a column direction from a first row to a last row among the rows of each of the first read area and the second read area.

A method for interleaving coded bits encoded at a prescribed code rate in a transmitter of a mobile communication system having a buffer comprised of a plurality of rows and columns, for writing the coded bits, the method comprising the steps of:

• separating the buffer into a first write area and a second write area according to a ratio of coded bits with higher priority among the coded bits to coded bits with lower priority;
• sequentially writing a stream of the coded bits with higher priority in a row direction from a first column to a last column among the columns in the first write area, and writing a stream of the coded bits with lower priority in a row direction from a last column to a first column among the columns in the second write area in such a manner that the stream of coded bits is written in a reverse direction from a last row to a first row in the second write area;
• permuting the columns in the buffer according to a given rule;
• dividing the rows in the buffer into a first read area and a second read area having equal size;
• permuting, between the first read area and the second read area, a number of rows equal to a number determined by a prescribed modulation technique among the rows of each of the first read area and the second read area;
• and
• sequentially reading the rows in the entire buffer in a column-direction from a first row to a last row.

A method for interleaving coded bits encoded at a prescribed code rate in a transmitter of a mobile communication system having two buffers each comprised of a plurality of rows and columns, for writing the coded bits, the method comprising the steps of:

• writing coded bits with higher priority among the coded bits in a first buffer and writing coded bits with lower priority in a second buffer, in such a manner that a stream of the coded bits with higher priority is sequentially written in a row direction from a first column to a last column among the columns of the first buffer and a stream of the coded with lower priority is sequentially written in a row direction from a first column to a last column among the columns of the second buffer;
• permuting the columns of the first buffer and the second buffer according to a given rule;
• and
• alternately reading a number of bits equal to a number determined by a prescribed modulation technique from the first buffer and the second buffer in such a manner that the bits are sequentially read in a column direction from a first row to a last row among the rows of each of the first buffer and the second buffer.

An apparatus for interleaving coded bits encoded at a prescribed code rate in a transmitter of a mobile communication system having an encoder for encoding transmission data into coded bits at the prescribed code rate, the coded bits including coded bits with higher priority and coded bits with lower priority, and a buffer having a plurality of rows and columns, for writing the coded bits, the apparatus comprising:

• an interleaver for separating the area of the buffer included therein into a first write area and a second write area according to a ratio of the coded bits with higher priority to the coded bits with lower priority, sequentially writing a stream of the coded bits with higher priority in a row direction from a first column to a last column among the columns in the first write area, and sequentially writing a stream of the coded bits with lower priority in a row direction from a first column to a last column among the columns in the second write area, and permuting the columns in the buffer area according to a given rule;
• and
• a multiplexer for dividing the rows in the buffer area into a first read area and a second read area having equal size, and alternately reading a number of bits equal to a number determined by a prescribed modulation technique from the first read area and the second read area in such a manner that the bits are sequentially read in a column direction from a first row to a last row among the rows of each of the first read area and the second read area, and multiplexing the read coded bits.

An apparatus for interleaving coded bits encoded at a prescribed code rate in a transmitter of a mobile communication system having an encoder for encoding transmission data into coded bits at the prescribed code rate, the coded bits including coded bits with higher priority and coded bits with lower priority, and a buffer having a plurality of rows and columns, for writing the coded bits, the apparatus comprising:

• an interleaver for separating the area of the buffer into a first write area and a second write area according to a ratio of the coded bits with higher priority to the coded bits with lower priority, sequentially writing a stream of the coded bits with higher priority in a row direction from a first column to a last column among the columns in the first write area, and writing a stream of the coded bits with lower priority in a row direction from a last column to a first column among the columns in the second write area in such a manner that the stream of coded bits is written in a reverse direction from a last row to a first row in the second write area, and permuting the columns in the buffer area according to a given rule;
• and
• a multiplexer for dividing the rows in the buffer area into a first read area and a second read area having equal size, alternately reading a number of bits equal to a number determined by a prescribed modulation technique from the first write area and the second write area, and sequentially reading coded bits in a column direction from a first row to a last row among the rows in the first read area and the second read area, and multiplexing the read coded bits.

An apparatus for interleaving coded bits encoded at a prescribed code rate in a transmitter of a mobile communication system having an encoder for encoding transmission data into coded bits at the prescribed code rate, the coded bits including coded bits with higher priority and coded bits with lower priority, and a buffer having a plurality of rows and columns, for writing the coded bits, the apparatus comprising:

• an interleaver for separating the area of the buffer into a first write area and a second write area according to a ratio of coded bits with higher priority to coded bits with lower priority, sequentially writing a stream of the coded bits with higher priority in a row direction from a first column to a last column among the columns in the first write area, and writing a stream of the coded bits with lower priority in a row direction from a last column to a first column among the columns in the second write area in such a manner that the stream of coded bits is written in a reverse direction from a last row to a first row in the second write area, permuting the columns in the buffer area according to a given rule, dividing the rows in the buffer area into a first read area and a second read area having equal size, and permuting, between the first read area and the second read area, a number of rows equal to a number determined by a prescribed modulation technique among the rows of each of the first read area and the second read area.

A method for deinterleaving coded bits demodulated by a prescribed demodulation technique in a receiver of a mobile communication system having a buffer comprised of rows and columns, for writing the coded bits, the method comprising the steps of:

• demultiplexing the coded bits at prescribed periods;
• separating the buffer into a first write area and a second write area having equal size;
• sequentially writing one demultiplexed output into the first write area and sequentially writing another demultiplexed output into the second write area;
• dividing the buffer into a first read area and a second read area according to a ratio of coded bits with higher priority among the coded bits to coded bits with lower priority;
• and
• reading coded bits from the first read area and the second read area according to the ratio of the coded bits with higher priority to the coded bits with lower priority.