CN101116276A

CN101116276A - System and method for space-time frequency coding in a multi-antenna transmission system

Info

Publication number: CN101116276A
Application number: CN200580040789.2A
Authority: CN
Inventors: 张建中; K·屈希; A·奥蒂南
Original assignee: Nokia Oyj
Current assignee: Nokia Technologies Oy
Priority date: 2004-11-03
Filing date: 2005-10-12
Publication date: 2008-01-30
Anticipated expiration: 2025-10-12
Also published as: ZA200704384B; CN101116276B

Abstract

A method for space-time-frequency coding pieces of data includes receiving a stream of a plurality of pieces of data in a multi-antenna transmission system, where the data may comprise a stream of orthogonal frequency division multiple access (OFDMA) symbols, orthogonal frequency division multiplexed (OFDM) symbols or the like. The pieces of data are then coded across space, time and frequency dimensions based upon a plurality of space-time-frequency (STF) codes. The pieces of data are coded such that one or more STF codes in the frequency dimension differ from one or more other STF codes in the frequency dimension. In this regard, the frequency dimension can include a plurality of frequency bins such that the pieces of data can be coded in a manner whereby the plurality of STF codes sequentially circulates through sets of at least one frequency bin in the frequency domain.

Description

System and method for space-time-frequency coding in a multi-antenna transmission system

Technical Field

The present invention relates generally to multiple antenna systems and methods for enabling wireless communications, and more particularly to multiple antenna systems and methods for space-time-frequency coding signals to provide diversity in enabling wireless communications.

Background

As wireless communication systems have evolved, wireless system design has become increasingly demanding in terms of equipment and performance requirements. Future wireless systems, referred to as third generation (3G) and fourth generation (4G) systems, will be needed to provide high quality data services at high transmission rates in addition to high quality voice services, as compared to first generation (1G) analog systems and second generation (2G) digital systems currently in use. There are device design constraints that strongly impact mobile terminal design while having system service performance requirements. It would be desirable for 3G and 4G wireless mobile terminals to be smaller, lighter, more power efficient units that are also capable of providing the complex voice and data services required for these future wireless systems.

Time-varying multipath fading is an effect in wireless systems in which a transmitted signal travels along multiple paths to a receiver, resulting in fading of the received signal due to the constructive and destructive summation of the signal at the receiver. Several methods are known for overcoming the effects of multipath fading, such as time interleaving using error correction coding, implementing frequency diversity by using spread spectrum techniques, or transmitter power control techniques. However, these techniques have drawbacks for use in both 3G and 4G systems. Time interleaving may introduce unnecessary delay, spread spectrum techniques may require allocation of a large bandwidth to overcome a large coherence bandwidth, and power control techniques may require higher transmitter power than is required by complex receiver-to-transmitter feedback techniques, which increases the complexity of the mobile terminal. All these drawbacks have a negative impact on the features required to implement third and fourth generation mobile terminals.

Antenna diversity is another technique used to overcome the effects of multipath fading in wireless systems. In transmit diversity, signals are multiplexed and processed to generate multiple separate signals, which are then transmitted via two or more physically separate antennas. Similarly, in receive diversity, two or more physically separated antennas are used to receive a signal, which is then processed through combining and switching to generate a received signal. Various systems known as multiple-input multiple-output (MIMO) systems utilize both transmit diversity and receive diversity, and provide multiplexing and diversity gains in wireless communications.

A transmit Diversity Technique is disclosed in U.S. patent No. 6,185,258 entitled Transmitter Diversity Technique for Wireless Communications, entitled 6/2/2001, to Alamouti et al, according to which two transmit antennas redundantly transmit information to a single receive antenna, the contents of which are incorporated herein by reference. According to the Alamouti transmit diversity technique, information is transmitted in the time domain during "time slots", the duration of which is small enough that the transmission quality on each of the two channels is effectively constant during the time slots. The time slot is divided into symbol periods, each symbol period representing the time at which a single symbol is transmitted from the antenna.

According to the Alamouti transmit diversity technique, in a time gap of duration two symbol periods, the first antenna transmits a symbol z during the first symbol period ₁ And transmitting symbol-z during a second symbol period ₂ ^* And the second antenna transmits a symbol z during the first symbol period ₂ And transmitting a symbol z during a second symbol period ₁ ^* . Here "a ^* "denotes the complex conjugate of" a "(i.e. if a = x + yj, then a ^* = x-yj). A time slot may be referred to as a "time-space slot" to indicate that multiple antennas are transmitting-emphasizing space diversity-or may simply be referred to as a "time slot". Alamouti matrix C _Ala Represented as follows, where each row corresponds to a transmit antenna and each column corresponds to a symbol period.

If one of the two antennas transmits more robustly than the other during a time slot, then two symbols can be derived from the stronger of the two transmissions alone. Forming new time slots during the third and fourth symbol periods, wherein z ₃ Acting as z ₁ Z, and z ₄ Acting as z ₂ And so on for subsequent time slots and corresponding symbol periods. Thus, the transmit antennas transmit according to a sequence of 2 x 2Alamouti codes. For representing symbol periodsThe type of matrix for transmit diversity, such as a 2 x 2Alamouti matrix, is referred to as a "space-time block code". Here, the space-time block code and the time slot happen to coincide, although this is not always the case. Diversity is here two or "double" in that each symbol is transmitted twice by the same replica of the delay or the complex conjugate of the delay (or the negative of the complex conjugate or the "negative complex conjugate"). The number of symbols transmitted per symbol period in a communication system is referred to as the "symbol rate" under the assumption that a single transmitter transmits one symbol per symbol period. The symbol rate is here unity, since a symbol is considered to be the same as its complex conjugate or negative complex conjugate for this purpose.

Unlike space-time coding techniques such as Alamouti transmit diversity techniques, space-frequency coding techniques rely on coding across space and frequency by: the symbol stream is divided into several parallel symbol streams and each of these streams is modulated onto a subcarrier or split carrier at a split frequency or within a split frequency bin. More coding techniques, referred to as space-time-frequency coding techniques, provide a combination of space-time coding and space-frequency coding by coding symbols among transmit antennas in time and frequency. While conventional space-time, space-frequency, and space-time-frequency coding techniques are sufficient to overcome at least some of the effects of multipath fading in wireless systems, it is generally desirable to improve such techniques.

Disclosure of Invention

In view of the foregoing background, exemplary embodiments of the present invention provide an improved multi-antenna transmitting communication entity, such as a base station, base station controller, etc., and an associated method and computer program product for space-time-frequency coding of data, such as for transmission across a wireless network. Similarly, exemplary embodiments of the present invention provide an improved receiving network entity, such as a mobile terminal, in a multi-antenna transmission system and an associated method and computer program product for space-time-frequency decoding of data, such as data received across a wireless network. Exemplary embodiments of the present invention can encode/decode data in a manner of increasing both diversity gain and coding gain in a communication system including a transmitting entity and a receiving entity. In this way, the exemplary embodiments of this invention enhance the performance of the communication system relative to conventional systems.

According to one aspect of the present invention, a method for space-time-frequency encoding a plurality of pieces of data is provided. The method includes receiving a plurality of streams of data in a multi-antenna transmission system, wherein the data may include streams of Orthogonal Frequency Division Multiple Access (OFDMA) symbols, orthogonal Frequency Division Multiplexing (OFDM) symbols, and/or the like. Regardless of the type of data, however, pieces of data are then encoded across a spatial dimension, a temporal dimension, and a frequency dimension based on a plurality of space-time-frequency (STF) codes. In this regard, the pieces of data are encoded such that one or more STF codes in the frequency dimension are different from one or more other STF codes in the frequency dimension. For example, pieces of data may be encoded based on a plurality of STF codes each comprising a matrix comprising a plurality of rows and columns, wherein the rows extend across the time dimension and the frequency dimension and the columns extend across the spatial dimension. In such instances, one or more STF codes may differ from one or more other STF codes due to the exchange of two or more lines in the one or more other STF codes.

The frequency dimension may include a plurality of frequency bins. In such instances, the pieces of data may be encoded such that the plurality of STF codes sequentially cycle through sets of at least one frequency bin in the frequency domain. Also in such instances, the pieces of data may be encoded to further cause the STF code for at least some of the respective sets of one or more frequency bins to be spread across the time domain within the respective sets of one or more frequency bins.

The method may be configured for a transmission system having four antennas. In such an embodiment, the pieces of data may be encoded based on at least three STF codes that sequentially cycle through sets of one or more frequency bins in the frequency domain. For example, in the case of a rate of one encoding, it may be based on the following three STF codes a ₁ 、A ₂ And A ₃ Encoding a plurality of pieces of data:

and wherein S ₁ 、S ₂ 、S ₃ And S ₄ Represents a plurality of pieces of data, and S ^* ₁ 、S ^* ₂ 、S ^* ₃ And S ^* ₄ Representing the complex conjugate of the corresponding pieces of data. Alternatively, for example in the case of a rate of two coding, it may be based on the following six STF codes B ₁ 、B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ Encoding a plurality of pieces of data:

and wherein S ₁ 、S ₂ 、S ₃ 、S ₄ 、S ₅ 、S ₆ 、S ₇ And S ₈ Represents a plurality of pieces of data, and S ^* ₁ 、S ^* ₂ 、 S ^* ₃ 、S ^* ₄ 、S ^* ₅ 、S ^* ₆ 、S ^* ₇ And S ^* ₈ Representing the complex conjugate of the respective pieces of data.

According to other exemplary aspects of the invention, a multi-antenna transmitting communication entity and a computer program product are provided for space-time-frequency encoding of data, as are a multi-antenna receiving communication entity, method and computer program product for space-time-frequency decoding of data, such as data received across a wireless network. As indicated above and as described below, the entities, methods and computer program products of exemplary embodiments of the present invention may encode/decode data in a manner that increases both diversity gain and coding gain in a communication system. These entities, methods and computer program products enhance the performance of a communication system as compared to conventional systems. Thus, the entities, methods and computer program products of exemplary embodiments of the present invention may solve the problems encountered by prior techniques and/or provide additional advantages.

Drawings

Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:

fig. 1 is a schematic block diagram illustrating a wireless communication system including a terminal according to an exemplary embodiment of the present invention;

fig. 2 is a schematic functional block diagram of a multi-antenna transmitting entity of the wireless communication system of fig. 1 according to an exemplary embodiment of the present invention;

fig. 3 is a schematic functional block diagram of a single-antenna receiving entity of the wireless communication system of fig. 1 according to an exemplary embodiment of the present invention;

fig. 4 illustrates space-time-frequency (STF) encoding of an input symbol stream using an STF code matrix a;

FIG. 5 illustrates a method of using a cyclic space-time-frequency (STF) code matrix A according to an exemplary embodiment of the present invention _k STF encoding of the input symbol stream;

FIG. 6 is a graph comparing a multiple-input-single-output (MISO) system with 4 antennas encoded with a matrix A to symbol stream ratio of one, and with a circulant matrix A, according to an exemplary embodiment of the invention _k Frame Error Rate (FER) for MISO systems with a rate of one encoding of the symbol stream; and

FIG. 7 is a graph comparing symbols with a matrix B according to an exemplary embodiment of the present inventionMISO system with 4 antennas with two-stream rate coding and method using circulant matrix B _k Frame Error Rate (FER) for MISO systems with rate two encoding of the symbol stream.

Detailed Description

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.

Referring to fig. 1, an illustration of one type of wireless communication system 10 that includes a terminal 12 that would benefit from the present invention is provided. The terminal may comprise a mobile telephone, as described below. It should be understood, however, that such a mobile telephone is merely illustrative of one type of terminal that would benefit from the present invention and, therefore, should not be taken to limit the scope of the present invention. While several embodiments of the terminal are illustrated and will be hereinafter described for purposes of example, other types of terminals, such as Portable Digital Assistants (PDAs), pagers, laptop computers and other types of voice and text communications systems, can readily employ the present invention. Furthermore, the system and method of the present invention will be primarily described in conjunction with mobile communications applications. It should be understood, however, that the system and method of embodiments of the present invention can be utilized in conjunction with a variety of other applications, both in the mobile communications industries and outside of the mobile communications industries.

Communication system 10 provides for radio communication between two communication stations, such as Base Station (BS) 14 and terminal 12, over a radio link formed between the two communication stations. The terminal is configured to receive and transmit signals to communicate with a plurality of base stations, including the illustrated base station. The communication system may be configured to operate in accordance with one or more of a plurality of different types of spread spectrum communications, or more particularly, one or more of a plurality of different types of spread spectrum communication protocols. More particularly, the communication system may be configured to operate in accordance with any of a number of 1G, 2G, 2.5G, and/or 3G communication protocols or the like. For example, the communication system may be configured to operate in accordance with 2G Wireless communication protocols IS-95 (CDMA) and/or CDMA 2000. As another example, the communication system may be configured to operate in accordance with a 3G wireless communication protocol such as Universal Mobile Telephone System (UMTS) utilizing Wideband Code Division Multiple Access (WCDMA) radio access technology. As another example, the communication system may be configured to operate in accordance with an enhanced 3G wireless communication protocol such as 1X-EVDO (TIA/EIA/IS-856) and/or 1X-EVDV. It should be understood that operation of embodiments of the present invention is similarly possible in other types of radio systems and other communication systems. Thus, while the following description will describe operation of embodiments of the present invention with respect to the aforementioned wireless communication protocols, operation of embodiments of the present invention may be similarly described with respect to any of various other types of wireless communication protocols without departing from the spirit and scope of the present invention.

The base station 14 is coupled to a Base Station Controller (BSC) 16. Which in turn is coupled to a Mobile Switching Center (MSC) 18. The MSC is coupled to a network backbone, here a PSTN (public switched telephone network) 20. A Correspondent Node (CN) 22 is in turn coupled to the PSTN. A communication path may be formed between the correspondent node and the terminal 12 by way of the PSTN, MSC, BSC, and base stations, as well as the radio links formed between the base stations and the terminal. Whereby communication of voice data and non-voice data can be achieved between the CN and the terminal. In the exemplary implementation shown, the base stations define cells, and a number of cell sites are located at spaced apart locations throughout a geographic area to define a plurality of cells within any of which terminals can communicate wirelessly with an associated base station in communication therewith.

The terminal 12 includes various means for performing one or more functions in accordance with exemplary embodiments of the present invention, including those more particularly shown and described herein. It should be understood, however, that the terminal may include alternative means for performing one or more like functions, without departing from the spirit and scope of the present invention. More particularly, as shown for example in fig. 1, a terminal of one embodiment of the invention may include, in addition to one or more antennas 24, a transmitter 26, a receiver 28, and a controller 30 or other processor that provides signals to and receives signals from the transmitter and receiver, respectively. These signals include signaling information in accordance with one or more communication protocols of the wireless communication system, and also user speech and/or user generated data. In this regard, the terminal may be capable of communicating in accordance with one or more of a number of different wireless communication protocols such as those described above. Although not shown, the terminals may also be capable of communicating in accordance with one or more wired and/or wireless networking techniques. More particularly, for example, the terminals may be capable of communicating in accordance with Local Area Network (LAN), metropolitan Area Network (MAN), and/or Wide Area Network (WAN) (e.g., the internet) wireline networking techniques. In addition, or in the alternative, the terminals may be capable of communicating in accordance with wireless networking techniques, including Wireless LAN (WLAN) techniques such as IEEE 802.11 and/or WiMax techniques such as IEEE 802.16, for example.

It is understood that the controller 30 includes the circuitry required for implementing the audio functions and logic functions of the terminal 12. For example, the controller may be comprised of a digital signal processor device, a microprocessor device, and/or various analog to digital converters, digital to analog converters, and other support circuits. The control and signal processing functions of the terminal are allocated between these devices according to their respective capabilities. The controller may also include an internal Voice Coder (VC) 30a and may include an internal Data Modem (DM) 30b. In addition, the controller may include functionality to operate one or more software applications, which may be stored in memory (as described below).

The terminal 12 may also comprise a user interface including a conventional earphone or speaker 32, a ringer 34, a microphone 36, a display 38, and a user input interface, all of which are coupled to the controller 18. The user input interface, which allows the terminal to receive data, can comprise any of a number of devices allowing the terminal to receive data, such as a keypad 40, a touch display (not shown) or other input device. In the embodiment comprising a keypad, the keypad comprises the conventional number keys (0-9) and the associated keys (#, #) as well as other keys for operating the terminal. Although not shown, the terminal may include one or more means for sharing and/or obtaining data (not shown).

Further, the terminal 12 can include memory that typically stores information elements related to a mobile subscriber, such as a Subscriber Identity Module (SIM) 42, a removable user identity module (R-UIM), or the like. In addition to the SIM, the terminal may include other removable and/or fixed memory. In this regard, the terminal can include volatile memory 44, such as volatile Random Access Memory (RAM) including a cache area for the temporary storage of data. The terminal can also include other non-volatile memory 46, which can be embedded and/or may be removable. In addition to or in lieu of this, non-volatile memory includes EEPROM, flash memory, and the like. The memories can store any of a number of software applications, instructions, pieces of information, and data, used by the terminal to implement the functions of the terminal.

From the description of the network of systems including the terminal 12, BS 14, BSC 16, MSC 18 and CN 22, it should be understood that the elements of the respective entities may be implemented by many various means, such as hardware and/or firmware, alone or under control of a computer program product. In general, the network entities may then comprise one or more logical units for implementing various functions of one of the respective entities. As will be appreciated, the logic unit may be implemented in any of a number of different ways. In this regard, the logic units to perform the functions of the respective entities may be implemented in an integrated circuit assembly that includes one or more integrated circuits, where the integrated circuit assembly is integral with or otherwise in communication with the respective entities. The design of integrated circuits is mainly achieved by highly automated processes. In this regard, complex and powerful software tools are available for converting a logic level design into a semiconductor circuit design ready to be etched and formed on a semiconductor substrate. Such as Avant! Software tools provided by corporation and Cadence Design of san jose, california automatically route conductor layouts and locate components on a semiconductor chip using well established rules of Design as well as a vast library of pre-stored Design modules. Once the design for a semiconductor circuit has been completed, the resulting design, in a standardized electronic format (e.g., opus, GDSII, or the like) may be transmitted to a semiconductor fabrication facility or "fab" for fabrication.

Reference is now made to fig. 2 and 3, which illustrate functional block diagrams of the system 10 of fig. 1, according to an exemplary embodiment of the present invention. More particularly, fig. 2 illustrates a functional block diagram of a multi-antenna transmission system including a transmission entity 50 (e.g., base station 14). As shown in fig. 3, the illustrated system operates as a multiple-input single-output (MISO) communication system that also includes a single-antenna receiving entity 66, such as terminal 12. It should be understood, however, that the system of the exemplary embodiment of the present invention is equally operable in other configurations without departing from the spirit and scope of the present invention. It should also be understood that the sending and receiving entities may be implemented into any of a number of different types of transmission systems that transmit encoded or unencoded digital transmissions over a radio interface.

In the illustrated MISO communication system 10, the transmitting entity 50 comprises a MISO transmitter having a space-time-frequency (STF) encoder 52, a spreading, filtering and modulation (SFM) block 54, and n transmit antennas 56 (four transmit antennas denoted antennas 56a-56 d). In the transmitting entity, a transmitter receives an input symbol stream x (t), such as an input Orthogonal Frequency Division Multiple Access (OFDMA) symbol stream, an input Orthogonal Frequency Division Multiplexing (OFDM) symbol stream, or the like. For an n-antenna transmitting entity, the STF encoder can receive a symbol stream x (t). In this regard, the symbol stream may include any of a number of different pieces of data, including, for example, symbols obtained from interleaved data encoded by a channel encoder, such as a convolutional encoder, a Turbo encoder, a LPDC (low density parity check) encoder, and so forth. Regardless of the exact nature of the received symbol stream, the STF encoder is able to encode every n symbols x (1), x (2),. X (n) according to an STF technique based on multiple STF codes, as explained below. The coded symbols of the symbol stream are then filtered and modulated by an SFM block and transmitted over n antennas.

At a receiving entity 60, the receiving entity comprises a receiver having a receive antenna 62, a filtering, despreading and demodulation (FDD) block 64 and an STF decoder 66. The receive antennas receive the data transmitted from the transmitting entity 50 and pass the data to an FDD block, which filters and demodulates a representation of the coded symbol stream from the transmitting entity. The STF decoder may then decode every n symbols x (1), x (2),. X (n) from the coded symbol representation according to the STF technique based on multiple STF codes, such as in the same manner as the STF encoder encodes the symbols of the input symbol stream, in a manner that minimizes the hamming distance, euclidean distance, etc. between the transmitted and received signals.

As described in the background section, according to the Alamouti transmit diversity technique, in a time slot with a duration of two symbol periods, a transmitter with two antennas encodes a symbol stream according to a 2 x 2Alamouti code or matrix. A matrix such as a 2 x 2Alamouti matrix used to represent transmit diversity in a symbol period is called a "space-time block code". According to another transmit diversity technique, the space-frequency technique relies on coding across space and frequency by: the symbol stream is divided into several parallel symbol streams and each of these streams is modulated onto subcarriers or split carriers at split frequencies or within split frequency bins. More coding techniques, known as space-time-frequency coding techniques, provide a combination of space-time coding and space-frequency coding by coding symbols in time and frequency between transmit antennas.

As will be appreciated, encoding a symbol stream according to a space-time-frequency encoding technique may differ by the encoding ratio of the symbol stream. Exemplary embodiments of the present invention will then be described with respect to coding rates of one, two and four. It should be understood, however, that the exemplary embodiments of this invention may be adapted for other code rates without departing from the spirit and scope of the present invention.

A. Rate one coding

As shown in fig. 4, in accordance with space-time-frequency coding techniques, it has previously been proposed that an STF encoder 52 encodes the symbol stream of a transmitting entity 50 having four antennas 56a-56d in accordance with an STF code having a ratio of one of:

as indicated above, two sets of consecutive columns of the code span two frequency subcarriers (or frequency bins) over two symbols of the input symbol stream, with the columns in each set spanning two time slots. Also as indicated above, the rows in the code span the antennas 56a-56d of the transmitting entity 50. The STF code matrix a is then repeated for pairs of time slots and frequency subcarriers in the time and frequency dimensions. Code a has second order diversity if coding is not considered. With sufficient coding, however, code a is able to achieve fourth order diversity, as described below in connection with the exemplary embodiments of the invention.

The signal model over the time slot and frequency pair of two symbols can be represented in matrix form as follows:

y＝A ^T h+n

wherein h = [ h = ₁ ，h ₂ ，h ₄ ]Representing the frequency-flat channel coefficient, A ^T Represents the code matrix transposition and N represents the variance per dimension (space, time, frequency) as N ₀ Additional White Gaussian Noise (AWGN) noise samples. Assuming Maximum Likelihood (ML) decoding by the STF decoder 66, the pair-wise error probability of the 4-antenna code in the AWGN channel may have an upper bound as follows:

in which the desired operation E is performed by channel statistics ₀ The diagonal matrix D comprises e.g. hamming distances, euclidean distances, etc. as seen by the channel coefficients along the error event path. Due to the presence of orthogonal STF codes, D = diag [ D [ ] ₁ ，d ₂ ，d ₃ ，d ₄ ]Diagonal entries of (a) occur in pairs. In other words, among the four STF symbols, the paired symbols experience the same channel due to space-time block coding.

The diversity order for the 4-antenna code depends on the rank of D. The presence of space-time block coding ensures the minimization of second-order diversity. Full fourth order diversity requires powerful channel codes. A binary convolutional code with a ratio of 1/2 can achieve such fourth order diversity.

As will be appreciated, by maximizing the trace of D (i.e., by maximizing the trace of D)

(representing hamming distance)) and ensures that D approximates the diagonal entries of the equation, the diversity gain and coding gain of the code shown can be maximized. In this regard, by setting d ₁ And d ₂ Are equal to each other (i.e. d) ₁ ＝d ₂ ) Diversity and coding gain can be maximized for a transmitting entity 50 having 4 antennas. In practice, it is often difficult to design codes with equal distances (e.g., hamming distance, euclidean distance, etc.) for all error events. Condition d ₁ ≠d ₂ Meaning a reduction, i.e. coding gain, and in particular at d ₁ And d ₂ There is a largeImbalance can result in severe losses in the system.

According to an exemplary embodiment of the present invention, STF encoder 52 is then able to encode the symbol stream in a manner that reduces the imbalance between the diagonal entries of D, thereby maximizing the coding gain. More particularly, the STF encoder of the exemplary embodiments of the present invention is capable of encoding pieces of data such as in a symbol stream based on a plurality of STF codes such that at least one STF code in the frequency dimension is different from at least one other STF code in the frequency dimension, as shown in fig. 5. In this regard, for a transmitting entity 50 having 4 antennas, the STF encoder may be capable of encoding the symbol stream according to an STF code having a ratio of one:

wherein S ₁ 、S ₂ 、S ₃ And S ₄ Represents a plurality of pieces of data (e.g., symbols), and S ^* ₁ 、S ^* ₂ 、S ^* ₃ And S ^* ₄ Representing the complex conjugate of the respective pieces of data (e.g., symbols).

Matrix A ₁ May (but need not) correspond to the matrix a previously proposed. Second and third matrices A ₂ 、A ₃ This can then be formed by: switching or otherwise switching matrices A ₁ Or matrix A ₂ And A ₃ So that all matrices differ by a switching of at least two rows. That is, matrix A may be exchanged ₁ The second and third rows of (a) to form a matrix a ₂ (or vice versa) and may pass through switch matrix a ₂ The third and fourth rows of (a) to form a matrix a ₃ . However, should beIt is to be understood that any of the three matrices may be formed by swapping at least two rows of any other matrix.

As shown in fig. 5, according to an exemplary embodiment of the present invention, the STF encoder 52 can be based on the STF code a described above ₁ 、A ₂ And A ₃ The symbol stream of the transmitting entity 50 having four antennas 56a-56d is encoded. As shown, as in the case of encoding the symbol stream in matrix a, two sets of consecutive columns of the code span two frequency subcarriers (or frequency bins) over two symbols, with the columns in each set spanning two time slots. Further, the rows in the code span the antennas of the transmitting entity. The STF code matrix may then be repeated for a plurality of pairs of time slots in the time dimension. However, in the frequency dimension including the frequency subcarrier number f =1, 2,. The FFT, the matrix may cycle sequentially through groups of at least one frequency subcarrier and more typically through groups of at least one pair of frequency subcarriers in the frequency dimension. Thus, the matrix may be repeated on frequency subcarrier pairs within a group of subcarriers, then cycle to the next matrix for the next group of subcarriers, and so on.

Number N of frequency subcarriers in a group over which the matrix is cycled _c Can be set in any of a number of different manners, such as, for example, by setting the number of subcarriers to two (i.e., N) _c = 2). In such an example, for the first N _c N subcarriers (i.e., f = 1.. N) _c ) To repeat the first matrix A ₁ After which the matrix loops to for the next N _c Sub-carriers(i.e., f = N) _c +1、...2N _c ) Matrix A of ₂ Then loop to for subsequent N _c Sub-carriers (i.e. f = 2N) _c +1、...3N _c ) Matrix A of ₃ . The matrix is then cycled back to the first matrix A ₁ And is repeated. In general, the matrix a of the FFT is numbered f =1, 2,. For a given subcarrier frequency _k Can be expressed as follows:

as indicated above, for cyclic code A ₁ 、A ₂ And A ₃ The pair-wise error probability of (c) takes the following form:

where a represents a diagonal matrix with entries,

unlike the acyclic case with diagonal matrix D, Λ now contains distinct diagonal entries and better approximates the equidistant criteria (i.e., the equidistant criteria

) Thereby providing an increase in coding gain. To better illustrate the enhanced performance achieved by the exemplary embodiments of the present invention, consider the graph of FIG. 6. In this regard, FIG. 6 compares a MISO system with 4 antennas, including an STF encoder 52 encoding the symbol stream with a matrix A, with another identical circulating matrix A, all in terms of a pedestrian B channel, a convolutional code with a ratio of 1/2, a Quadrature Phase Shift Keying (QPSK) modulated symbol stream _k Frame Error Rate (FER) of an STF encoder that encodes a symbol stream. As shown in the figure, with a circulant matrix A _k Encoding the symbol stream may result in a coding gain of, for example, up to 0.7dB or more above encoding the symbol stream with matrix a. Similar gains may be exhibited for other modulation modes and coding modes.

As can be appreciated, the exemplary embodiments of this invention are equally applicable to transmitting entities 50 having different numbers of antennas 56, to different coding ratios, and/or to matrices a of different sizes _k . For example, the exemplary embodiments of this invention may be equally applicable to a transmitting entity having three antennas 56a-56c, such as in a similar manner as described above.

As another example, exemplary embodiments of the present invention may be equally applicable to a transmitting entity 50 having six or eight antennas 56. In this regard, for a transmitting entity having 6 antennas, STF encoder 52 may be capable of encoding a stream of symbols according to an STF code having a ratio of one as follows:

as indicated above, this may be through switch matrix a ₁ The second and third rows of (a) to form a matrix a ₂ (or vice versa) can pass through switch matrix A ₂ To form a matrix a ₃ Can pass through a switching matrix A ₃ To form a matrix a ₄ And may pass through switch matrix a ₄ To form a matrix a ₅ . In general, one can start with or the first matrix A ₁ Initially by switching the previous matrix a _1-1 The k-th and (k + 1) -th rows in (b) form a matrix a _k . It should be noted, however, that rows in a matrix may be swapped with any of a number of other patterns to form subsequent matrices. Therefore, the STF encoder of the transmitting entity having 8 antennas can be based on the STF code a of the following ratio 1 ₁ The symbol stream is encoded, from which other STF codes A can be derived ₂ -A ₇ ：

It should be understood that the STF encoder 52 of a transmitting entity 50 having 5 or 7 antennas 56 may derive STF codes from these STF codes for transmitting entities having 6 or 8 antennas, respectively. More particularly, the STF code may be derived by coupling together rows in a matrix of transmitting entities with increasing antennas (e.g., 6 or 8 antennas) and allocating the coupled rows to the same antennas of transmitting entities with decreasing antennas (5 or 7 antennas). The coupled rows may then be considered as a single row for row swapping in order to derive a matrix for the antennas.

B. Coding with a ratio of two

Similar to the rate one coding case, it has previously been proposed that the STF encoder 52 encodes the symbol stream of the transmitting entity 50 having four antennas 56a-56d according to the following rate two STF code:

as indicated above, two sets of consecutive columns of the code span two frequency subcarriers (or frequency bins) over two symbols, with the columns in each set spanning two time slots. Also as indicated above, the rows in the code span the antennas 56a-56d of the transmitting entity 50. Similar to the foregoing and in contrast to conventional encoding techniques, the STF encoder of exemplary embodiments of the present invention is capable of encoding pieces of data, such as in a symbol stream, based on a plurality of STF codes, such that at least one STF code in the frequency dimension is different from at least one other STF code in the frequency dimension. In this regard, for a transmitting entity 50 having 4 antennas, the STF encoder may be capable of encoding the symbol stream according to an STF code having a ratio of two: .

Matrix B ₁ May (but need not) correspond to the matrix B previously proposed. Second to sixthMatrix B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ This can then be formed by: switching or otherwise switching matrix B ₁ Or matrix B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ At least two rows in one of the other matrices, such that all matrices differ by the exchange of at least two rows. However, with cycle A _k As in the case of matrices, it is to be understood that six matrices B _k Any one matrix may be formed by swapping at least two rows of any other matrix.

Also with cycle A _k Similarly in the case of matrices, the STF encoder 52 can be based on the STF code B described above ₁ 、B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ The symbol stream of the transmitting entity 50 having four antennas 56a-56d is encoded. As before, two sets of consecutive columns of the code span two frequency subcarriers (or frequency bins) over two symbols, with the columns in each set spanning two time slots. Further, the rows in the code span the antennas of the transmitting entity. The STF code matrix may then be repeated for a plurality of pairs of time slots in the time dimension. However, in the frequency dimension including the frequency subcarrier number f =1, 2,. The FFT, the matrix may cycle sequentially through a plurality of groups of at least one frequency subcarrier and more typically through a plurality of groups of at least one pair of frequency subcarriers in the frequency dimension. Thus, the matrix may be a frequency subcarrier within a group of subcarriersRepeat the upper one and then cycle to the next matrix for the next set of subcarriers, and so on.

Number N of frequency subcarriers in a group on which a matrix is cycled _c Can be set in any of a number of different manners, such as, for example, by setting the number of subcarriers to two (i.e., N) _c = 2). In such an example, for the first N _c N subcarriers (i.e., f = 1.. N) _c ) To repeat the first matrix B ₁ After which the matrix loops to the next N _c Sub-carriers (i.e. f = N) _c +1、...2N _c ) Matrix B of ₂ Then loop to for subsequent N _c Sub-carriers (i.e. f = 2N) _c +1、...3N _c ) Matrix B of ₃ . The matrix continues to loop until matrix B ₆ And then loops back to the first matrix B ₁ And is repeated. In general, the matrix B of the FFT is numbered f =1, 2,. For a given subcarrier frequency _k Can be expressed as follows:

to better illustrate the enhanced performance achieved by the exemplary embodiment of the present invention for the case where the ratio is two, consider the graph of FIG. 7. Similar to fig. 6, fig. 7 compares 4-antenna with respect to a walk-a channel, a rate 1/2 convolutional code, a Quadrature Phase Shift Keying (QPSK) modulated symbol stream, each including an STF encoder 52 encoding the symbol stream with a matrix B, using a Linear Minimum Mean Square Error (LMMSE) receiving entity 60MISO system and with circulant matrix B _k The Frame Error Rate (FER) of the STF encoder 52 that encodes the symbol stream. As shown, with a circulant matrix B _k Encoding the symbol stream may result in a coding gain of, for example, up to 1.0dB or more above encoding the symbol stream with matrix B. Similar gains may be exhibited for other modulation modes and coding modes.

And one in the case of a ratio of oneAlso, the exemplary embodiments of this invention are equally applicable to transmitting entities 50 having different numbers of antennas 56, to different coding ratios, and/or to different sizes of matrices B _k . For example, exemplary embodiments of the present invention are equally applicable to a 4 × 6 circulant matrix B _k In which B is _k Can be expressed as follows:

and from which other matrices B can be derived ₂ -B ₆ . In such an example, three pairs of consecutive columns of the code span three frequency subcarriers (or frequency bins) over two symbols, with the columns in each set spanning two time slots. Further, the rows in the code span the antennas 56a-56d of the transmitting entity 50. Alternatively, six columns may span six frequency subcarriers over one symbol, or may span one subcarrier over six symbols.

C. Coding with ratio of four (and three)

For example, for the coding case with a ratio of four, with 8 antennas 56, the circulant matrix B may be derived from the following first STF code matrix B1 ₂ 、B ₃ 、B ₄ 、B ₅ 、B ₆ And B ₇ ：

According to the matrix B, a number of different ways are possible, such as in the manner described above ₁ A matrix B can be derived ₂ 、B ₃ 、B ₄ 、B ₅ 、B ₆ And B ₇ . The matrix B is derived anyway _k The STF encoder 52 of the transmitting entity 50 with 8 antennas can then encode the input symbol stream in a cyclic manner in the frequency domain using those matrices as described above. In such an embodimentIn an example, rows in the matrix may be mapped to antennas of the transmitting entity, and columns may beTo map to different input symbols or different subcarriers.

It should also be noted that the matrix B is based on the STF code for the case where the ratio is four _k The STF code matrix B for the case of a ratio of three can be derived _k . In such an example, by considering only matrix B with a ratio of four _k Six out of eight rows in (B) may derive a matrix B _k 。

The functions performed by one or more of the entities of the system, such as the terminal 12, BS 14, BSC 16, MSC 18, and/or CN 22, may be performed by various means, such as hardware and/or firmware, alone and/or under the control of one or more computer program products, according to an example embodiment of the present invention. The one or more computer program products for performing one or more functions of embodiments of the invention include at least one computer-readable storage medium, such as the non-volatile storage medium, and software including computer-readable program code portions, such as a series of computer instructions, embodied in the computer-readable storage medium.

In this regard, FIG. 5 is a control flow diagram of a method, system, and program product according to exemplary embodiments of the invention. It will be understood that each block or step of the control flow block diagrams, and combinations of blocks in the control flow block diagrams, can be implemented by various means, such as hardware, firmware, and/or software including one or more computer program instructions. As will be appreciated, any such computer program instructions may be loaded onto a computer or other programmable apparatus (i.e., hardware) to produce a machine, such that the instructions which execute on the computer or other programmable apparatus create means for implementing the functions specified in the control flow block diagram block(s) or step(s). These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the control flow block diagram block(s) or step(s). The computer program instructions may also be loaded onto a computer or other programmable apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the control block flow diagram block(s) or step(s).

Accordingly, blocks or steps of the control flow block diagrams support combinations of means for performing the specified functions, combinations of steps for performing the specified functions and program instruction means for performing the specified functions. It will also be understood that each block or step of the control flow block diagrams, and combinations of blocks or steps in the control flow block diagrams, can be implemented by special purpose hardware-based computer systems which perform the specified functions or steps, or combinations of special purpose hardware and computer instructions.

Many modifications and other embodiments of the invention will come to mind to one skilled in the art to which this invention pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. A multi-antenna communication entity, comprising:

a space-time-frequency (STF) unit capable of processing a plurality of streams of data,

wherein the space-time unit is capable of encoding the pieces of data across a space dimension, a time dimension, and a frequency dimension based on a plurality of STF codes, the pieces of data being encoded such that at least one STF code in the frequency dimension is different from at least one other STF code in the frequency dimension.

2. The multi-antenna communication entity of claim 1, wherein the STF unit is capable of encoding the pieces of data based on a plurality of STF codes each comprising a matrix comprising a plurality of rows and a plurality of columns, the rows extending across the time dimension and frequency dimension and the columns extending across the space dimension, and

wherein at least one STF code differs from at least one other STF code by the exchange of at least two rows of the other STF codes.

3. A multi-antenna communication entity according to claim 1, wherein the frequency dimension includes a plurality of frequency bins, and wherein the STF element is capable of encoding the pieces of data such that the plurality of STF codes sequentially circulate through sets of at least one frequency bin in the frequency domain.

4. A multi-antenna communication entity according to claim 3, wherein the STF element is capable of encoding the pieces of data further such that the STF code for at least some of the respective sets of at least one frequency bin is spread across the time domain at the respective sets of at least one frequency bin.

5. A multi-antenna communication entity according to claim 3, applicable for four antennas, wherein said STF unit is capable of encoding said pieces of data based on at least three STF codes sequentially cycling through sets of at least one frequency bin in the frequency domain.

6. The multi-antenna communication entity of claim 5,wherein the STF unit can be based on the following three STF codes A ₁ 、A ₂ And A ₃ Encoding the plurality of pieces of data:

and wherein S ₁ 、S ₂ 、S ₃ And S ₄ Represents a plurality of pieces of data, and S ^* ₁ 、S ^* ₂ 、S ^* ₃ And S ^* ₄ Representing the complex conjugate of the respective pieces of data.

7. The multi-antenna communication entity of claim 5, wherein the STF element is capable of being based on the following six STF codes B ₁ 、B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ Encoding the plurality of pieces of data:

and wherein S ₁ 、S ₂ 、S ₃ 、S ₄ 、S ₅ 、S ₆ 、S ₇ And S ₈ Represents a plurality of pieces of data, and S ^* ₁ 、S ^* ₂ 、 S ^* ₃ 、S ^* ₄ 、S ^* ₅ 、S ^* ₆ 、S ^* ₇ And S ^* ₈ Represents the complex conjugate of the respective pieces of data.

8. A network entity in a multi-antenna transmission system, the entity comprising:

wherein the space-time unit is capable of decoding the pieces of data across a space dimension, a time dimension, and a frequency dimension based on a plurality of STF codes, the pieces of data decoded such that at least one STF code in the frequency dimension is different from at least one other STF code in the frequency dimension.

9. A network entity according to claim 8, wherein the STF unit is capable of decoding the pieces of data based on a plurality of STF codes each comprising a matrix including a plurality of columns and a plurality of rows, the rows extending across the time and frequency dimensions and the columns extending across the space dimension, and

wherein at least one STF code differs from at least one other STF code by an exchange of at least two rows of the other STF codes.

10. A network entity according to claim 8, wherein the frequency dimension includes a plurality of frequency bins, and wherein the STF element is capable of decoding the pieces of data such that the plurality of STF codes sequentially cycle through sets of at least one frequency bin in the frequency domain.

11. The network entity of claim 10, wherein the STF unit is capable of decoding the pieces of data further such that the STF code for at least some of the respective sets of at least one frequency bin extends across the time domain at the respective sets of at least one frequency bin.

12. A network entity according to claim 10, adapted for a transmission system having four antennas, wherein the STF unit is capable of decoding the pieces of data based on at least three STF codes sequentially cycling through sets of at least one frequency bin in the frequency domain.

13. The network entity of claim 12, wherein the STF element is capable of being based on the following three STF codes a ₁ 、A ₂ And A ₃ Decoding the pieces of data:

14. A network entity according to claim 12, wherein the STF element is capable of being based on the following six STF codes B ₁ 、B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ Decoding the plurality of pieces of data:

15. A method of space-time-frequency encoding a plurality of pieces of data, the method comprising:

receiving a plurality of streams of data in a multi-antenna transmission system; and the number of the first and second groups,

encoding the pieces of data across a spatial dimension, a time dimension, and a frequency dimension based on a plurality of space-time-frequency (STF) codes, the pieces of data being encoded such that at least one STF code in the frequency dimension is different from at least one other STF code in the frequency dimension.

16. A method according to claim 15, wherein the pieces of data are encoded based on a plurality of STF codes each comprising a matrix including a plurality of rows and a plurality of columns, the rows extending across the time and frequency dimensions and the columns extending across the space dimension, and

17. A method according to claim 15, wherein the frequency dimension comprises a plurality of frequency bins, and wherein the encoding step comprises encoding the pieces of data such that the plurality of STF codes sequentially circulate through sets of at least one frequency bin in the frequency domain.

18. A method according to claim 17, wherein said encoding step comprises encoding the pieces of data further such that the STF code for at least some of the respective sets of at least one frequency bin extends across the time domain at the respective sets of at least one frequency bin.

19. The method of claim 17, wherein the receiving step comprises receiving a plurality of streams of data in a transmission system having four antennas, and

wherein the encoding step comprises encoding the pieces of data based on at least three STF codes sequentially cycling through sets of at least one frequency bin in the frequency domain.

20. The method of claim 19, wherein the encoding step comprises encoding based on the following three STF codes a ₁ 、A ₂ And A ₃ Encoding the plurality of pieces of data:

and wherein S ₁ 、S ₂ 、S ₃ And S ₄ Representing a plurality of pieces of dataAnd S is ^* ₁ 、S ^* ₂ 、S ^* ₃ And S ^* ₄ Representative instituteThe complex conjugate of the corresponding pieces of data.

21. The method of claim 19, wherein the encoding step comprises encoding based on six STF codes B ₁ 、B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ Encoding the plurality of pieces of data:

and wherein S ₁ 、S ₂ 、S ₃ 、S ₄ 、S ₅ 、S ₆ 、S ₇ And S ₈ Represents a plurality of pieces of data, and S ^* ₁ 、S ^* ₂ 、 S ^* ₃ 、S ^* ₄ 、S ^* ₅ 、S ^* ₆ 、S ^* ₇ And S ^* ₈ Represents a complex conjugate of the respective pieces of data.

22. A method of space-time-frequency decoding a plurality of pieces of data, the method comprising:

receiving a plurality of streams of data in a multi-antenna transmission system; and

decoding the pieces of data across a spatial dimension, a time dimension, and a frequency dimension based on a plurality of space-time-frequency (STF) codes, the pieces of data decoded such that at least one STF code in the frequency dimension is different from at least one other STF code in the frequency dimension.

23. The method of claim 22, wherein the pieces of data are decoded based on a plurality of STF codes each comprising a matrix comprising a plurality of rows and a plurality of columns, the rows extending across the time dimension and the frequency dimension and the columns extending across the space dimension, and

24. A method according to claim 22, wherein the frequency dimension comprises a plurality of frequency bins, and wherein the decoding step comprises decoding the pieces of data such that the plurality of STF codes sequentially circulate through sets of at least one frequency bin in the frequency domain.

25. A method according to claim 24, wherein the decoding step comprises decoding the pieces of data further such that the STF code for at least some of the respective sets of at least one frequency bin extends across the time domain at the respective sets of at least one frequency bin.

26. The method of claim 24, wherein the receiving step comprises receiving multiple data streams in a transmission system having four antennas, and

wherein the decoding step comprises decoding the pieces of data based on at least three STF codes sequentially cycling through sets of at least one frequency bin in the frequency domain.

27. The method of claim 26, wherein the decoding step comprises decoding based on the following three STF codes a ₁ 、A ₂ And A ₃ Decoding the plurality of pieces of data:

28. The method of claim 26, wherein the decoding step comprises decoding based on the following six STF codes B ₁ 、B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ Decoding the plurality of pieces of data:

29. A computer program product for space-time-frequency encoding a plurality of pieces of data, the computer program product comprising at least one computer-readable storage medium of at least one anchor network entity, the at least one computer-readable storage medium having computer-readable program code portions stored therein, the computer-readable program code portions comprising:

a first executable portion for receiving a plurality of streams of data in a multi-antenna transmission system; and the number of the first and second groups,

a second executable portion for encoding the pieces of data across a spatial dimension, a temporal dimension, and a frequency dimension based on a plurality of space-time-frequency (STF) codes, the pieces of data being encoded such that at least one STF code in the frequency dimension is different from at least one other STF code in the frequency dimension.

30. The computer program product of claim 29, wherein the second executable portion is adapted to encode the pieces of data based on a plurality of STF codes that each include a matrix including a plurality of rows and a plurality of columns, the rows extending across the time dimension and the frequency dimension and the columns extending across the space dimension, and

31. A computer program product according to claim 29, wherein the frequency dimension includes a plurality of frequency bins, and wherein the second executable portion is adapted to encode the pieces of data such that the plurality of STF codes sequentially cycles through sets of at least one frequency bin in the frequency domain.

32. A computer program product according to claim 31, wherein the second executable portion is adapted to encode the pieces of data further such that the STF code for at least some of the respective sets of at least one frequency bin extends across the time domain at the respective sets of at least one frequency bin.

33. The computer program product of claim 31, wherein the first executable portion is adapted to receive a plurality of streams of data in a transmission system having four antennas, and

wherein the second executable portion is adapted for encoding the pieces of data based on at least three STF codes sequentially cycling through sets of at least one frequency bin in the frequency domain.

34. The computer program product of claim 33, wherein the second executable portion is adapted to be based on the following three STF codes a ₁ 、A ₂ And A ₃ Encoding the plurality of pieces of data:

35. The computer program product of claim 33, wherein the second executable portion is adapted to be based on the following six STF codes B ₁ 、B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ Encoding the plurality of pieces of data:

36. A computer program product for space-time-frequency decoding a plurality of pieces of data, the computer program product comprising at least one computer-readable storage medium of at least one anchor network entity, the at least one computer-readable storage medium having a computer-readable program decoding portion stored therein, the computer-readable program decoding portion comprising:

a first executable portion for receiving a plurality of streams of data in a multi-antenna transmission system; and

a second executable portion for decoding the pieces of data across a spatial dimension, a temporal dimension, and a frequency dimension based on a plurality of space-time-frequency (STF) codes, the pieces of data decoded such that at least one STF code in the frequency dimension is different from at least one other STF code in the frequency dimension.

37. The computer program product of claim 36, wherein the second executable portion is adapted to decode the pieces of data based on a plurality of STF codes that each include a matrix comprising a plurality of rows and a plurality of columns, the rows extending across the time dimension and the frequency dimension and the columns extending across the space dimension, and

38. A computer program product according to claim 36, wherein the frequency dimension includes a plurality of frequency bins, and wherein the second executable portion is adapted to decode the pieces of data such that the plurality of STF codes sequentially cycle through sets of at least one frequency bin in the frequency domain.

39. A computer program product according to claim 38, wherein the second executable portion is adapted to decode the pieces of data further such that the STF code for at least some of the respective sets of at least one frequency bin is spread across the time domain at the respective sets of at least one frequency bin.

40. The computer program product of claim 38, wherein the first executable portion is adapted to receive a plurality of streams of data in a transmission system having four antennas, and

wherein the second executable portion is adapted for decoding the pieces of data based on at least three STF codes sequentially cycling through sets of at least one frequency bin in the frequency domain.

41. The computer program product of claim 40, wherein the second executable portion is adapted to be based on the following three STF codes A ₁ 、A ₂ And A ₃ Decoding the pieces of data:

and wherein S ₁ 、S ₂ 、S ₃ And S ₄ Represents a plurality of pieces of data, and S ^* ₁ 、S ^* ₂ 、S ^* ₃ And S ^* ₄ Represents the complex conjugate of the respective pieces of data.

42. The computer program product of claim 40, wherein the second executable portion is adapted to be based on the following six STF codes B ₁ 、B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ Decoding the pieces of data:

43. A terminal for space-time-frequency coding pieces of data, comprising:

first means for receiving a plurality of streams of data in a multi-antenna transmission system; and the number of the first and second groups,

second means for encoding a plurality of pieces of data across a spatial dimension, a time dimension, and a frequency dimension based on a plurality of space-time-frequency (STF) codes, the pieces of data being encoded such that at least one STF code in the frequency dimension is different from at least one other STF code in the frequency dimension.

44. A terminal according to claim 43, wherein the second means is adapted to encode the pieces of data based on a plurality of STF codes each comprising a matrix comprising a plurality of rows and a plurality of columns, the rows extending across the time and frequency dimensions and the columns extending across the space dimension, and

45. A terminal according to claim 43, wherein the frequency dimension includes a plurality of frequency bins, and wherein the second means is adapted to encode the pieces of data such that the plurality of STF codes sequentially circulates through sets of at least one frequency bin in the frequency domain.

46. A terminal according to claim 45, wherein the second means is adapted to encode the pieces of data further such that the STF code for at least some of the respective sets of at least one frequency bin is spread across the time domain at the respective sets of at least one frequency bin.

47. The terminal according to claim 45, wherein said first means is adapted to receive a plurality of streams of data in a transmission system having four antennas, and

wherein the second means is adapted to encode the pieces of data based on at least three STF codes sequentially cycling through sets of at least one frequency bin in the frequency domain.

48. A terminal according to claim 47, wherein the second means is adapted to be based on the following three STF codes A ₁ 、A ₂ And A ₃ Encoding the plurality of pieces of data:

49. A terminal according to claim 47, wherein the second means is adapted to be based on the following six STF codes B ₁ 、B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ Encoding the plurality of pieces of data:

50. A terminal for space-time-frequency decoding a plurality of pieces of data, comprising:

first means for receiving a plurality of streams of data in a multi-antenna transmission system; and

second means for decoding the pieces of data across a spatial dimension, a time dimension, and a frequency dimension based on a plurality of space-time-frequency (STF) codes, the pieces of data decoded such that at least one STF code in the frequency dimension is different from at least one other STF code in the frequency dimension.

51. A terminal according to claim 50, wherein the second means is adapted to decode the pieces of data based on a plurality of STF codes each comprising a matrix comprising a plurality of rows and a plurality of columns, the rows extending across the time and frequency dimensions and the columns extending across the spatial dimension, and

52. A terminal according to claim 50, wherein the frequency dimension comprises a plurality of frequency bins, and wherein the second means is adapted to decode the pieces of data such that the plurality of STF codes sequentially circulate through sets of at least one frequency bin in the frequency domain.

53. A terminal according to claim 52, wherein the second means is adapted to decode the pieces of data further such that the STF code for at least some of the respective sets of at least one frequency bin is spread across the time domain at the respective sets of at least one frequency bin.

54. The terminal according to claim 52, wherein said first means is adapted to receive a plurality of streams of data in a transmission system having four antennas, and

wherein the second means is adapted to decode the pieces of data based on at least three STF codes sequentially cycling through sets of at least one frequency bin in the frequency domain.

55. A terminal according to claim 54, wherein the second means is adapted to be based on the following three STF codes A ₁ 、A ₂ And A ₃ Decoding the plurality of pieces of data:

and wherein S ₁ 、S ₂ 、S ₃ And S ₄ Represents a plurality of pieces of data, and S ^* ₁ 、S ^* ₂ 、A ^* ₃ And S ^* ₄ Representing the complex conjugate of the respective pieces of data.

56. The terminal according to claim 54, wherein the second means is adapted to be based on the following six STF codes B ₁ 、B ₂ 、B ₃ 、B ₄ 、B ₅ And B ₆ Decoding the pieces of data:

and wherein S ₁ 、S ₂ 、S ₃ 、S ₄ 、S ₅ 、S ₆ 、S ₇ And S ₈ Represents a plurality of pieces of data, and S ^* ₁ 、 S ^* ₂ 、S ^* ₃ 、S ^* ₄ 、S ^* ₅ 、S ^* ₆ 、S ^* ₇ And S ^* ₈ Represents a complex conjugate of the respective pieces of data.