Abstract:
A mobile communication terminal including a Central Processing Unit (CPU) configured to set at least one or more predetermined parameters according to communication channel states, and a Hybrid Automatic Repeat reQuest (HARQ) transmission/reception processor configured to process input data based on the set at least one or more predetermined parameters.

Description:
RELATED APPLICATION 
   The present application claims priority to Korean Application No. 10-2005-0119049, filed on Dec. 7, 2005, which is hereby incorporated by reference in its entirety. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a mobile communication terminal and corresponding method that processes input data based at least one or parameters corresponding to changeful radio channel states. 
   2. Background of the Invention 
   A mobile communication terminal allows people to wirelessly communicate with each other via a communication network including a MSC (Mobile Switching Center) and a plurality of BSs (Base Stations). Mobile terminals also provide the user with the ability to transmit data including symbols, numerals and characters as well as multimedia data. 
   In addition, mobile terminals use a variety of different communication techniques such as the Code Division Multiple Access (CDMA) technique, Time Division Multiple Access (TDMA) technique, Frequency Division Multiple Access (FDMA) technique, and Global System for Mobile Communications (GSM) technique. Further, the International Telecommunication Union (ITU) has selected the International Mobile Telecommunication 2000 (IMT-2000) system as the third generation (3G) mobile communication system to provide improved multimedia services. 
   In more detailed, the 3G system increases the mobile terminal&#39;s capabilities to include services such as a wireless LAN, digital multimedia broadcast, portable Internet, etc. These additional services use a High Speed Downlink Packet Access (HSDPA) method that is based on the asynchronous IMT-2000. The HSDPA method increases the downlink transmission speed and thus decreases the transmission delay. 
   Turning now to  FIG. 1 , which illustrates a related art transmitting mobile communication terminal. As shown, the terminal includes a Central Processing Unit (CPU)  100  for controlling various units of the terminal, and a Cyclic Redundancy Checksum (CRC) unit  200  for adding CRC bits to input data and for packeting the data, a channel coder  300  for performing a channel coding process for the packeted data. Also included is a Hybrid Automatic Repeat request (HARQ) transmission and reception processors  410  and  420  for processing the coded data based on a preset Forward Error Correction (FEC) coding rate, channel interleavers  500  and  510  for channel-interleaving the processed data, a modulator  600  for modulating the interleaved data, and an antenna  700  for transmitting the modulated data. 
   In more detail,  FIG. 2  illustrates processes performed by the transmitting terminal shown in  FIG. 1 . As shown, the input data is packeted into a preset size (S 210 ). That is, the mobile terminal receives data to be transmitted and adds CRC bits used for error detection to thereby enable the packeting of the data to have the preset size. Then, a channel coding process is performed on the packeted data (S 220 ), and the channel-coded data is processed according to a preset FEC coding rate (S 230 ). That is, when transmitting the packeted data, the mobile terminal uses a preset FEC coding rate to thereby improve an error correction function. 
   Next, the processed data is subject to a channel interleaving process (S 240 ). The mobile terminal interleaves the processed data to reduce the probable loss of the data during the data transmission. The channel-interleaved data is then mapped to a physical channel (S 250 ), and the mapped data is modulated and then transmitted (S 260 ). Further, the mobile terminal modulates the mapped data using a preset method such as the BPSK, QPSK, 8PSK, 16QAM, 64QAM methods to thereby allow the transmission of the modulated data to a receiving side mobile terminal. 
   However, the related art mobile terminal transmits the data using a preset FEC coding rate, etc. regardless of a channel state, which disadvantageously affects a communication quality when the state of the channel changes. 
   SUMMARY OF THE INVENTION 
   Accordingly, one object of the present invention is to address the above-noted and other problems. 
   Another object of the present invention is to provide a mobile communication terminal supporting extended link adaptation techniques and corresponding method that efficiently uses channels according to changeful radio channel states by varying at least one or more predetermined parameters according to the channel states. 
   To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, the present invention provides in one aspect a mobile communication terminal including a Central Processing Unit (CPU) configured to set at least one or more predetermined parameters according to communication channel state, and a Hybrid Automatic Repeat request (HARQ) transmission/reception processor configured to process input data based on the set at least one or more predetermined parameters. 
   In another aspect, the present invention provides a mobile communication method, which includes setting at least one or more predetermined parameters according to communication channel state, and processing input data based on the set at least one or more predetermined parameters. 
   Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. 
     In the drawings: 
       FIG. 1  is a block diagram illustrating a related art transmitting side mobile terminal; 
       FIG. 2  is a flowchart illustrating a method for supporting link adaptation techniques according to the related art; 
       FIG. 3  is a block diagram illustrating a transmitting side mobile terminal for supporting extended link adaptation techniques in accordance with an embodiment of the present invention; 
       FIG. 4  is a flowchart illustrating a method for supporting extended link adaptation techniques in accordance with an embodiment of the present invention; 
       FIGS. 5A and 5B  are block diagrams illustrating various channel coders of  FIG. 3 ; 
       FIG. 6  is a overview illustrating a CQI (Channel Quality Indicator) transmitting method for supporting extended link adaptation techniques in accordance with an embodiment of the present invention; and 
       FIG. 7  is a block diagram illustrating a receiving side mobile terminal for supporting extended link adaptation techniques in accordance with an embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. In more detail,  FIG. 3  is a block diagram illustrating a transmitting side mobile terminal for supporting extended link adaptation techniques in accordance with an embodiment of the present invention. 
   As shown, the transmitting side mobile terminal includes a CPU  150  for setting at least one or more predetermined parameters according to channel states, a CRC unit  250  for adding CRC bits to input data to thereby packet the data having the CRC bits, a channel coding unit  350  including at least one or more channel coders for channel-coding the packeted data based upon the set parameters, a HARQ transmission processor  450  for processing the channel-coded data based on the set parameters, a channel interleaver unit  550  including at least one or more channel interleavers for channel-interleaving the processed data based on the set parameters, a modulator  650  for modulating the interleaved data, and an antenna  750  for transmitting the modulated data. 
   Turning next to  FIG. 4 , which is a flowchart illustrating a method for supporting extended link adaptation techniques in accordance with an embodiment of the present invention.  FIG. 3  will also be referred to in this description. 
   As shown, the method includes first setting at least one or more predetermined parameters according to channel states (S 410 ). That is, the CPU  150  sets at least one or more predetermined parameters according to a variety of channel states, and outputs the set parameters to the channel coding unit  350 , the HARQ transmission processor  450  and the channel interleaver unit  550 . In addition, the at least one or more set parameters include, for example, channel coders using different types of channels codes, a Forward Error Correction (FEC) coding rate, Rate Matching (RM) patterns, different types of channel interleavers, interleaving patterns, ARP types, etc. 
   Then, the method packets the input data into a preset size (S 420 ), and channel-codes the packeted data based on the set parameters (S 430 ). That is, the CRC unit  250  receives data to be transmitted and adds CRC bits for error detection to thus enable a packeting of the data having the CRC bits into the preset size. Further, the at least one or more channel coders included in the channel coding unit  350  perform the channel coding process for the packeted data based upon the set parameters (S 430 ). Here, the at least one or more channel coders use different channel codes such as the block Code (BC), Convolutional Code (CC), Turbo Code (TC), Serial Concatenated Convolutional Code (SCCC), Turbo-Like Code (TLC), etc. For example,  FIG. 5A  illustrates an SCCC coder in which a first coder is connected in series with a second coder, and  FIG. 5B  illustrates a TC coder in which the first coder is connected in parallel with the second coder. 
   Returning to  FIG. 4 , the channel-coded data is then processed based on the set parameters (S 440 ). That is, the HARQ transmission processor  450  processes the channel-coded data based upon the set parameters. The HARQ transmission processor  450  may select one ARQ method such as the Stop-And-Wait (SAW) ARQ method, the Selective Repeat (SR) ARQ method, etc. In addition, the HARQ transmission processor  450  improves an error correction function by adjusting the FEC coding rate and also maximizes a time diversity effect by adjusting a puncturing pattern used in the RM. Further, the HARQ transmission processor  450  reduces an error flow by adjusting the interleaver pattern to thus enable packet transmissions with a high reliability. 
   Next, the processed data is channel-interleaved based on the set parameters (S 450 ). The channel interleaver unit  550  uses a channel interleaver such as a random interleaver, block interleaver, etc. That is, the channel interleaver unit  550  interleaves the processed data to minimize a loss of data even if the data loss is generated during the data transmission. The interleaved data is then mapped to a physical channel to which the data is to be transmitted (S 460 ), and the mapped data is modulated and then transmitted to the desired receiving side mobile terminal (S 470 ). 
   In more detail, the modulator  650  modulates the mapped data using a mapping method such as a Binary Phase Shift Keying (BPSK) method, a Quadrature Phase Shift Keying (QPSK) method, an 8PSK method, a 16 Quadrature Amplitude Modulation (QAM) method, a 64QAM method, etc. The modulator  650  also transmits the modulated data to a receiving side mobile communications terminal via the antenna  750 . 
   Further, to set the at least one or more predetermined parameters according to various channel states, the mobile terminal provides a corresponding base station with the various channel states via a Channel Quality Indicator (CQI). A method for transmitting the CQI will be explained with reference to  FIG. 6 . 
   As illustrated in  FIG. 6 , the transmitting side mobile terminal transmits an extended CQI corresponding to a transmittal NACK, which indicates a packet loss. The terminal also periodically transmits the CQI to the base station. Thus, the transmitting mobile terminal informs the base station about the channel state using the extended CQI, and accordingly can change the at least one or more set parameters based upon the transmitted extended CQI. In addition, a High Speed-Downlink Shared Channel (HS-DSCH) denotes a downlink high data channel, and a High Speed-Dedicated Physical Control Channel (HS-DPCCH) denotes an uplink control channel which contains information required for the HS-DSCH processing. 
   Turning next to  FIG. 7 , which is a block diagram of a receiving mobile terminal for supporting the extended link adaptation techniques in accordance with an embodiment of the present invention. As shown, the receiving mobile terminal includes substantially the same components as the transmitting mobile terminal (i.e., the CPU  150 , the CRC unit  250 , the HARQ processor  450  and the antenna  750 ). The receiving terminal also includes a demodulator  660  for demodulating the received data, a channel interleaver unit  560  including at least one or more channel deinterleavers for channel-deinterleaving the demodulated data based upon the set parameters, and a channel decoding unit  360  including at least one or more channel decoders for decoding the processed data based upon the set parameters. The explanation of the receiving terminal for supporting extended link adaptation techniques according to the present invention is similar to that of the transmitting terminal. Accordingly, a detailed explanation of the receiving terminal is omitted. 
   As described above, the mobile terminal and corresponding method for supporting the extended link adaptation techniques according to the present invention advantageously performs an optimal transmission according to various channel states by changing at least one or more set parameters according to the channel states, so as to enable an efficient usage of the channels according to the changeable radio channel states. 
   As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalence of such metes and bounds are therefore intended to be embraced by the appended claims.