Data-rate detection in CDMA systems

A computer readable medium having computer-executable instructions for an improved data-rate detection in a cellular radio communication system including multiple transport channels supporting variable data-rate transmissions, comprising:

• receiving a signal including a succession of frames, wherein the signal in each of the succession of frames includes data and Transport Format Channel Information (TFCI) associated with each of the multiple transport channels, the Transport Format Channel Information comprising a Transport Format Combination Set (TFCS) table and Transport Format Combination Indicators (TFCIs), where the TFCIs index the elements of the TFCS, the TFCIs having a length of K bits, where K is the minimum number of bits required to represent every member of the TFCS uniquely, the TFCIs being padded with N-K zeros to get words of length N, and N-bit padded TFCI words being encoded into TFCI code words using a suitable TFCI encoding logic;
• obtaining a maximum number of valid transport format combinations that can be formed using the multiple transport channels from a given set of the TFCS table;
• obtaining the number K as the minimum number of bits required to represent every member of the TFCS distinctly;
• obtaining a maximum number of TFCIs that can be formed using the TFCS as the number of words where the K bits are potentially non-zero and the remaining N-K bits are set to zero;
• computing a subset of valid TFCI code words as the TFCI code words corresponding to the TFCI words;
• and
• decoding the TFCI over the space of only the computed subset of valid TFCI code words or with higher weight given to the space of the computed subset of valid TFCI code words as compared to other possible TFCI code words to reduce computation during decoding and to improve TFCI detection reliability.

A computer readable medium having computer-executable instructions for an improved data-rate detection in a communication system including multiple transport channels supporting variable data-rate transmissions, comprising:

• receiving TFCI and data associated with each of the multiple transport channels in the cellular radio communication system;
• separating the TFCI from data associated with each of the multiple transport channels to obtain the TFCI associated with each of the multiple transport channels, the Transport Format Channel Information comprising a Transport Format Combination Set (TFCS) table and Transport Format Combination Indicators (TFCIs), where the TFCIs index the elements of the TFCS, the TFCIs having a length of K bits, where K is the minimum number of bits required to represent every member of the TFCS uniquely, the TFCIs being padded with N-K zeros to get words of length N, and N-bit padded TFCI words being encoded into TFCI code words using a suitable TFCI encoding logic;
• decoding separated TFCI code words to obtain a Transmission Time Interval (TTI) associated with each of the TFCI code words;
• obtaining a minimum Transmission Time Interval (TTI_min) and a maximum Transmission Time Interval (TTI_max) from the obtained TTI associated with each of the TFCIs;
• decoding a subset of TFCI code words to obtain transport formats associated with each of the TFCI code words;
• repeating the decoding of the TFCIs after TTI_min;
• and
• repeating the above receiving, separating, decoding, obtaining, and decoding steps at the end of TTI_max.

A computer system for detecting data-rate detection signal received from a transmitter capable of transmitting data at a plurality of data rates, comprising:

• a storage device;
• an output device;
• and
• a processor programmed to repeatedly perform a method, comprising:
• receiving the signal including a succession of frames, wherein each of the succession of frames includes data and Transport Format Channel Information (TFCI) associated with each of the multiple transport channels, the Transport Format Channel Information comprising a Transport Format Combination Set (TFCS) table and Transport Format Combination Indicators (TFCIs), where the TFCIs index the elements of the TFCS, the TFCIs having a length of K bits, where K is the minimum number of bits required to represent every member of the TFCS uniquely, the TFCIs being padded with N-K zeros to get words of length N, and N-bit padded TFCI words being encoded into TFCI code words using a suitable TFCI encoding logic;
• obtaining a maximum number of valid transport format combinations that can be formed for the multiple transport channels from a given set of the TFCS table;
• obtaining the number K as the minimum number of bits required to represent every member of the of the TFCS distinctly;
• obtaining a maximum number of TFCIs that can be formed using the TFCS as the number of words where the K bits are potentially non-zero and the remaining N-K bits are set to zero;
• computing a subset of valid TFCI code words using the obtained maximum number of valid transport format combinations and the obtained maximum number of TFCIs;
• and
• decoding the TFCI over the space of only the computed subset of valid TFCI code words or with higher weight given to the space of the computed subset of valid TFCI code words as compared to other possible TFCI code words to reduce computation during decoding and to improve data-rate detection reliability.

A receiver for data-rate detection in a cellular radio communication system including multiple transport channels supporting variable data-rate transmissions, comprising:

• a demodulator to receive TFCI and data associated with each of the transport channels from a transmitter and to further separate the received TFCI from the data;
• a TFCI decoder to receive the separated TFCI, comprising:
• a TFCI Selection Logic Device to obtain a maximum number of valid TFCs that can be formed using the transport channels from a given set of TFCS within a frame, wherein the device further obtains a maximum number of TFCIs that can be formed using the TFCS within the frame, and the device further computes a subset of TFCI code words using the obtained maximum number of valid TFCIs and the maximum number of TFCI code words that can be formed using the TFCS;
• and
• a FHT decoder to decode the TFCI over the space of only the computed subset of TFCI code words within the frame or with higher weight given to the space of the computed subset of valid TFCI code words as compared to other possible TFCI code words to reduce computation during decoding and to further improve data-rate detection reliability;
• and
• a transport channel multiplexer to receive the separated data and output the data to respective transport channels using the decoded subset of TFCI code words.