Method and apparatus of turbo encoder

Briefly, an apparatus, a method and a wireless communication device are provided. The wireless communication device includes a turbo encoder to generate an encoded data block and a transmitter to transmit a data sub-block of the encoded data block in a time slot of a physical channel of the wireless communication system. The encoded data block includes real time data.

BACKGROUND OF THE INVENTION

Wireless communication systems such as, for example, cellular communication systems may include a plurality of modulation and coding schemes. The modulation and coding schemes may be determined by a cellular standard which is used by the wireless communication system. An example for cellular standard may be Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS), Enhanced Data for GSM Evolution (EDGE) and the like.

According to industry standard of third generation of cellular communication system, a logical channel set which termed as Enhanced Circuit Switched Data (E-CSD) may be envisioned as a suitable medium for the provision of video telephony. Video telephony has been targeted by the GSM cellular service providers as a method for providing increased revenue, as compared with regular voice telephony, and as a means of contending with a similar video telephony service provided through wideband Code Division Multiple Access (WCDMA) technology. However, E-CSD, as currently defined in the GSM standard, may not provide a level of quality required by the video telephony service over all the cell coverage area.

DETAILED DESCRIPTION OF THE INVENTION

Some portions of the detailed description, which follow, are presented in terms of algorithms and symbolic representations of operations on data bits or binary digital signals within a computer memory. These algorithmic descriptions and representations may be the techniques used by those skilled in the data processing arts to convey the substance of their work to others skilled in the art.

Unless specifically stated otherwise, as apparent from the following discussions, it is appreciated that throughout the specification discussions utilizing terms such as “processing,” “computing,” “calculating,” “determining,” or the like, refer to the action and/or processes of a computer or computing system, or similar electronic computing device, that manipulate and/or transform data represented as physical, such as electronic, quantities within the computing system's registers and/or memories into other data similarly represented as physical quantities within the computing system's memories, registers or other such information storage, transmission or display devices. In addition, the term “plurality” may be used throughout the specification to describe two or more components, devices, elements, parameters and the like. For example, “plurality of mobile stations” describes two or more mobile stations

It should be understood that the present invention may be used in a variety of applications. Although the present invention is not limited in this respect, the circuits and techniques disclosed herein may be used in many apparatuses such as receivers of a radio system. Receivers intended to be included within the scope of the present invention include, by way of example only, wireless local area network (WLAN) receivers, two-way radio receivers, digital system receivers, analog system receivers, cellular radiotelephone receivers and the like.

Types of cellular radiotelephone systems intended to be within the scope of the present invention include, although are not limited to, Code Division Multiple Access (CDMA) and wideband CDMA (WCDMA) cellular radiotelephone portable devices for transmitting and receiving spread spectrum signals, Global System for Mobile communication (GSM) cellular radiotelephone, Time Division Multiple Access (TDMA), General Packet Radio Service (GPRS), Extended GPRS, and the like.

Some embodiments of the invention may be implemented, for example, using a machine-readable medium or article which may store an instruction or a set of instructions that, if executed by a machine (for example, by stations of wireless communication system, and/or by other suitable machines), cause the machine to perform a method and/or operations in accordance with embodiments of the invention. Such machine may include, for example, any suitable processing platform, computing platform, computing device, processing device, computing system, processing system, computer, processor, or the like, and may be implemented using any suitable combination of hardware and/or software. The machine-readable medium or article may include, for example, any suitable type of memory unit, memory device, memory article, memory medium, storage device, storage article, storage medium and/or storage unit, for example, memory, removable or non-removable media, erasable or non-erasable media, writeable or re-writeable media, digital or analog media, hard disk, floppy disk, Compact Disk Read Only Memory (CD-ROM), Compact Disk Recordable (CD-R), Compact Disk Rewriteable (CD-RW), optical disk, magnetic media, various types of Digital Versatile Disks (DVDs), a tape, a cassette, or the like. The instructions may include any suitable type of code, for example, source code, compiled code, interpreted code, executable code, static code, dynamic code, or the like, and may be implemented using any suitable high-level, low-level, object-oriented, visual, compiled and/or interpreted programming language, e.g., C, C++, Java, BASIC, Pascal, Fortran, Cobol, assembly language, machine code, or the like.

Turning toFIG. 1, a wireless communication system such as, for example, a cellular communication system100in accordance with exemplary embodiment of the invention, is shown. Although the scope of the present invention is not limited in this respect, cellular system100may include a base station110, a mobile station120, an uplink130and a downlink140. Uplink130and downlink140may include one or more physical channels In some embodiments of the invention, a peer to peer wireless communication may be used. In those embodiments, uplink130and downlink140may not be used. In accordance with embodiments of the invention, a channel may be depicted as a physical transfer medium that may be used to transfer signals. Furthermore, a channel may be a combination of the physical transfer medium, components of the transmitter and/or receiver and may include channel taps (for example, symbols).

Although the scope of the present invention is not limited in this respect, base station110may include an at least a transmitter115and mobile station120may include an at least a transmitter125, if desired. According to at least one embodiment of the invention, base station110and mobile station120may be capable to transmit data and voice over the physical channels of the downlink140and uplink130, respectively. For example, the data may be a video telephony conversation, a voice over internet protocol conversation, interactive game between one mobile station to another mobile station and the like. With embodiments of the invention, transmitters115and/or transmitter120may transmit a data sub-block of an encoded data block in a time slot of one of the downlink140and/or uplink130physical channels, if desired. In some embodiments of the invention a turbo encoder may generate the encoded data block which includes real time data such as, for example, video, voice, game data or the like.

Turning toFIG. 2, a block diagram of a communication device200of a wireless communication system, according to an exemplary embodiment of the invention is shown. Although the scope of the present invention is not limited in this respect, communication device200may be a base station or a mobile station of a cellular system such as, for example GSM, and may include a data block generator210, a error detection code encoder220, a turbo encoder230, an interleaver240, a mapper250, a transmitter260and an antenna210.

Although the scope of the present invention is not limited in this respect, with embodiments of the invention, data block generator220may generate a data block which include a real time data. For example, the real time data may include voice data packets, video data packets, gaming data packets, music data packets, audio data packets or the like. In some embodiments of the invention, data block generator may be an application such as, for example, a video telephony application, a voice over internet protocol application, a game or the like.

Although the scope of the present invention is not limited in this respect, in some embodiments of the invention error correction/detection code encoder220may encode the data block with error correction codes such as for example, cyclical redundancy code (CRC),FIRE code, Reed Solomon code (RS) or the like. In some other embodiments, error correction/detection code encoder220may encode the data block with error detection codes such as, for example CRC. It should be understood that some embodiments of the invention may not include error correction/detection code encoder220.

Although the scope of the present invention is not limited in this respect, turbo encoder230may include turbo encoder for parallel code concatenation (PCC), or turbo encoder for serial code concatenation (SCC), or turbo encoder for hybrid code concatenation (HCC) or the like. In one exemplary embodiment of the invention, turbo encoder230may receive data block210and encode the data block with rate 1/3, if desired. For example, data block210may include 640 bits and turbo encoder230may output an encoded data block235which includes, for example 1368 bits.

Although the scope of the present invention is not limited in this respect, turbo encoder230may output encoded data block235. In this exemplary embodiment, interleaver240may partition the encoded data block into two or more interleaved data sub-blocks245, wherein two or more interleaved data sub-block245may be mapped to two or more physical channels, respectively. For example, the logical channels may be modulated with different modulation schemes according to the GSM modulation schemes e.g. receive Gaussian Minimum Shift Keying (GMSK) and/or 8 phase Slift Keying (8PSK) if desired.

c(n,k)—may depict the data block that may enter interleaver240, wherein n may be a block number and k may be a number of bits in block n;

i(B,j)—may depict the data block which output interleaver240, wherein B may be a number of the output interleaved data block and j may be an index of the bit in a transmitted burst. For example, the result of the interleaving is a distribution of the reordered 1368 bits of encode data block235, n=N, over 19 data sub-blocks, 18 bits equally distributed in each data sub-block, in a diagonal way over consecutive blocks, if desired.

According to an exemplary embodiment of the invention, the interleaved data sub-block may include 1368 bits. Interleaver240and mapper230may distribute the bits of the interleaved data sub-block into 22 bursts, if desired. For example, 18 bits may be equally distributed in the first and 22ndbursts, 36 bits may be distributed in the second and 21stbursts, 54 bits be distributed in the third and 20thbursts and 72 bits may be distributed in the other 16 bursts. In this exemplary embodiment of the invention, the encoded data block may be interleaved “diagonal”, where a new encoded data block may start with every fourth burst and may be distributed over 22 bursts, if desired.

Although the scope of the present invention is not limited in this respect, mapper250may map the bits of an interleaved data sub-block to mapped data sub-blocks also referred in the art as bursts, wherein a bit may be map to two or more mapped data sub-block. The mapped data sub-blocks (e.g. bursts) may be transmitted over two or more time slots252of the physical channel For example, mapped data sub-blocks255may be include in a frame252which may be transmitted within seven time slots252(e.g. time slot0, time slot1. . . time slot7). For example, the bit may be transmitted in time slot0and/or in time slot1by transmitter unit260and antenna270, if desired.

Although the scope of the present invention is not limited in this respect, in some embodiments of the invention, communication device200may be a dual mode mobile station which may operate in two mode of operations such as, for example GSM and WCDMA. In this exemplary embodiment of the invention, turbo encoder230may encode the data block according to GSM modulation schemes and according WCDMA modulation schemes, if desired.

Although the scope of the present invention is not limited in this respect, antenna210may be an omni-directional antenna, a monopole antenna, a dipole antenna, an end fed antenna, a circularly polarized antenna, a micro-strip antenna, a diversity antenna, an internal antenna, or the like.