DE29825109U1 - Transmitter diversity technique - Google Patents

Abstract

Technique employs a coder responding to input symbols to form a set of channel symbols incorporating redundancy. The coder uses replications plus negations for some symbols. An output stage applies the symbols to transmitter antennae to form at least two distinct channels. The coder forms a negative of the input symbols, and forms a complex conjugate or negative complex conjugate of the input symbol.

Description

The The present invention relates to wireless communication and especially on techniques for effective wireless communication in the presence of fading and other deteriorations.

The most effective countermeasure there is a wireless radio channel in the event of multipath shrinkage in compensating for the effect of the fading on the transmitter by the Power of the transmitter is controlled. That is, if the channel conditions are known on the transmitter (on one side of the connection), then can the transmitter pre-distorts the signal to the effects of the channel at the recipient (on the other side) to overcome. However, there are two basic problems with this approach. The first problem is the dynamic range of the transmitter, so the Transmitters overcome a loss of x dB can, it must increase its power by x dB, which is due in most cases limitations on radiation power, size and cost the amplifier is not practical. The second problem is that the transmitter has none Know about has the channel as seen by the broadcaster (except for Systems with time division duplex, at which the transmitter power from a known other transmitter over the same channel). So if you have a transmitter based on channel properties channel information must be transmitted from the receiver to the transmitter causing a deterioration in throughput and an additional complexity is caused both at the transmitter and at the receiver.

Other effective techniques are time diversity and frequency diversity. The usage a time interleaving together with an encoding can be a Improve diversity entail. The same applies to frequency hopping and the spread spectrum technique. However, the time interleaving leads too unnecessary huge delays when the channel changes slowly. Accordingly, frequency diversity techniques are ineffective if the coherence bandwidth of the channel is big (slight spread of delay).

It is well known in most scattered environments an antenna diversity the most appropriate and Most effective technique represents the effects of reusable shrinkage to reduce. The classic approach to antenna diversity exists in it, at the receiver use multiple antennas and a combination (or selection) perform, about the quality to improve the received signal.

The Main problem when using the principle of recipient diversity in usual wireless communication systems like IS-136 and GSM are the restrictions in terms of cost, size and power consumption the recipient. For obvious reasons are small size, weight and cost priority. The addition of multiple antennas and radio chains (or selection and switching circuits) in receivers is present impossible. Therefore, diversity techniques were often only used the transmission quality in the upward direction (Receiver base) with a variety of antennas (and receivers) to improve the base station. Because a base station is often thousands of recipients served, it is more economical To upgrade base stations than the recipients.

Recently some interesting approaches for one transmitter diversity stimulated. A delay diversity system was proposed by A. Wittneben in “Base Station Modulation Diversity for Digital SIMULCAST ", Proceeding of the 1991 IEEE Vehicular Technology Conference (VTC 41 st), pp. 848-853, May 1991, and in “A New Bandwidth Efficient Transmit Antenna Modulation Diversity Scheme For Linear Digital Modulation ", in Proceeding of the 1993 IEEE International Conference on Communications (IICC 1993), pp. 1630-1634, May 1993. The proposal is to that a base station transmits a sequence of symbols through an antenna and the same Sequence of symbols - but delayed - by another antenna.

U.S. Patent 5,479,448, Nambirajan Seshadri, December 26, 1995, discloses a similar arrangement in which a sequence of codes is interrogated by two antennas. The code sequence is forwarded by a cyclical switch that successively directs each code to the different antennas. Because copies of the same symbol are transmitted by different antennas at different times, you can achieve both a space and a time diversity. An MLSE (maximum likelihood sequence estimator) or an MMSE (minimum mean squared error) equalization is then used to dissolve the multiplicity distortion and to achieve a diversity gain. See also N. Seshadri, JH Winters, "Two Signaling Schemes for Improving the Error Performance of FDD Transmission Systems Using Transmitter Antenna Diversity," Proceeding of the 1993 IEEE Vehicular Technology Conference (VTC 43 ^rd ), pp. 508-511, May 1993 ; and JH Winters, "The Di versity Gain of Transmit Diversity in Wireless Systems with Rayleigh Fading, "Proceeding of the 1994 ICC / SUPERCOMM, New Orleans, Vol. 2, pp. 1121-1125, May 1994.

On another interesting approach is revealed by Tarokh, Seshadri, Calderbank and Naguib in U.S. Application No. 08/847635, dated 25 April 1997 (based on preliminary registration from November 7th 1996), when the symbols correspond to the antennas by which they broadcast simultaneously be encoded and decoded using a maximum likelihood (Maximum probability) decoder is used. In particular the process at the transmitter processes the information in blocks of M1 bits, where M1 is a multiple of M2, i.e., M1 = k * M2. He converts each successive group of M2 bits into information symbols um (generating k information symbols) encodes each sequence of k information symbols in n channel codes (develops one Group of n channel codes for each sequence of k information symbols) and turns each code one Group of codes for a different antenna.

The Problems of the prior art systems are overcome and progress in technology is achieved with a simple one Block coding arrangement in which symbols transmit over a plurality of transmission channels and coding just simple arithmetic operations includes such as negation and conjugation. The diversity that of the transmitter is generated uses space diversity and either time diversity or frequency diversity. Spatial diversity is achieved by redundantly over transmit a variety of antennas becomes; time diversity is achieved by transmitting redundantly at different times becomes; and frequency diversity is achieved by transmitting redundantly at different frequencies becomes. For example, if you use two transmit antennas and a single one Receiving antenna, one of the embodiments shown provides the same diversity gain like the MRRC (maximal-ratio receiver combining) system with one Transmitting antenna and two receiving antennas. The new approach does not require an increase in bandwidth or feedback from the recipient to the transmitter and has the same decoding complexity as the MRRC. The diversity improvement is the same as when using MRRC (maximal-ratio receiver combining) at the recipient with the same number of antennas. The basics of this invention can on Arrangements with more than two antennas are used and one exemplary embodiment shown the same room lock code with two transmitter and receiver antennas used. This system ensures the same diversity gain like an MRRC with four branches.

1 Figure 3 is a block diagram of a first embodiment in accordance with the principles of this invention;

2 Figure 3 shows a block diagram of a second embodiment in which no channel estimates are used;

3 Figure 3 shows a block diagram of a third embodiment in which channel estimates are derived from the recovered signals; and

4 explains an embodiment in which two transmitter antennas and two receiver antennas are used.

According to the basics This invention provides effective communication through coding of symbols that only have negations and conjugations of Symbols (which is in fact a mere negation of the imaginary part) in combination with a transmitter-generated diversity. Space diversity and either frequency diversity or time diversity are used.

1 Figure 3 shows a block diagram of an arrangement in which two controllable aspects of the transmitter that are used are space and time. That is, the arrangement out 1 comprises several transmitter antennas (which ensure spatial diversity) and uses several time intervals. In particular, the transmitter includes 10 for example the antennas 11 and 12 and it processes incoming data in blocks of n symbols, where n is the number of transmit antennas, and in the exemplary embodiment of FIG 1 is 2, and each block takes n symbol intervals to be transmitted. The arrangement of FIG 1 a recipient 20 which is a single antenna 21 having.

Rauschen von Störungen und anderen Quellen wird zu den beiden empfangenen Signalen addiert und daher ist das resultierende Basisbandsignal, das zu jeder Zeit empfangen wird und von der Empfangs- und Verstärkungseinheit 25 ausgegeben wird,

wobei s_i und s_j die Signale sind, die jeweils von den Sendeantennen 11 und 12 gesendet werden.At a given time, a signal transmitted by a transmit antenna experiences interference effects from the channel being traversed, which consists of the transmit chain, the air link, and the receive chain. The channel can be modeled by a complex multiplicative distortion factor, which is composed of a size response and a phase response. The following illustration will therefore the channel transmission function from the transmitting antenna 11 to the receiving antenna 21 denoted by h ₀ and from the transmitting antenna 12 to the receiving antenna 21 with h ₁ , where

Noise from interferences and other sources is added to the two received signals and therefore is the resulting baseband signal that is received at all times and from the receiving and amplifying unit 25 is spent

where s _i and s _{j are} the signals, respectively, from the transmitting antennas 11 and 12 be sent.

As mentioned above, in the two-antenna embodiment, the 1 each block has two symbols and two symbol intervals are required to transmit these two symbols. In particular if the symbols s _i and s _j are to be transmitted, the transmitter applies the signal s _i to the antenna during a first time interval 11 and the signal s _j to the antenna 12 on and in the next time interval the transmitter sends the signal –s ₁ * to the antenna 11 and the signal s ₀ * to the antenna 12 on. This is obviously a very simple coding process, using only negations and conjugations. As shown below, it is as effective as it is simple. According to the transmissions described above, the received signal is in the first time interval r (t) = h 0 s i + h 1 s j + n (t), (3) and in the next time interval is the received signal

Table 1 explains the transmission pattern from the two antennas of the arrangement 1 for a sequence of signals {s ₀ , s ₁ , s ₂ , s ₃ , s ₄ , s ₅ , ...}.

Table 1

The received signal is sent to the channel estimator 22 which provides signals representing the channel characteristics or rather the best estimates thereof. These signals are sent to the combiner 23 and to the maximum likelihood detector 24 created. The estimates made by the channel estimator 22 can be obtained by sending a known training signal that the channel estimator 22 and the channel estimates are calculated based on the recovered signal. This is a well known practice.

The combiner 23 receives the signal in the first time interval, latches, receives the signal in the next time interval, and combines the two received signals to develop the following signals.

wobei

wodurch gezeigt ist, dass die Signale der Gleichung (6) tatsächlich Abschätzungen der übertragenen Signale (innerhalb eines multiplikativen Faktors) sind. Entsprechend werden die Signale der Gleichung (6) an den Maximum-Likelihood-Detektor 24 gesendet.Substituting equation (1) into equation (5), we get:

in which

which shows that the signals of equation (6) are actually estimates of the transmitted signals (within a multiplicative factor). The signals of equation (6) are sent to the maximum likelihood detector accordingly 24 Posted.

wobei d²(x, y) der quadrierte euklidische Abstand zwischen den Signalen x und y ist, d.h.Attempting to recover s _i considers two types of signals: the signals that are actually received at time t and t + T, and the signals that should have been received if s _{i were} the signal that was sent. As shown below, no assumption is made as to the value of s _j . That is, a decision is made that s _i = s _x for the value of x, for the

where d ² (x, y) is the squared Euclidean distance between the signals x and y, ie

d. h. unabhängig von dem übertragenen Symbol ist, und dass

d. h. unabhängig von dem übertragenen Symbol ist, kann Gleichung (7) umgeschrieben werden und es ergibt sich

wobei

oder gleichbedeutend,By realizing that

ie independent of the symbol transmitted, and that

ie independent of the symbol transmitted, equation (7) can be rewritten and the result is

in which

or equivalent,

, und daher kann die Entscheidungsregel von Gleichung (9) vereinfacht werden zu wähle Signal ŝ_i = s_x genau dann, wenn With phase shift keying modulation, all symbols carry the same energy, which means

, and therefore the decision rule of equation (9) can be simplified to choose signal ŝ _i = s _x if and only if

und

von dem Abschätzer 22, entwickelt die Abstände

, identifiziert x, für das die Gleichung (10) gilt und schließt, dass ŝ_i = s_x. Ein ähnlicher Prozess wird angewendet, um ŝ_j wiederzugewinnen.Therefore, the maximum likelihood detector develops 24 the signals s _k for all values of k using

and

from the appraiser 22 , develops the distances

, identifies x to which equation (10) applies and concludes that ŝ _i = s _x . A similar process is used to recover ŝ _j .

und

wiedergewonnen. Es können jedoch auch andere Vorgehensweisen zur Rückgewinnung der übertragenen Signale verwendet werden. Tatsächlich existiert eine Ausführungsform für die Rückgewinnung von übertragenen Symbolen, bei der die Kanalübertragungsfunktionen überhaupt nicht bestimmt werden müssen, vorausgesetzt, dass ein Anfangspaar von übertragenen Signalen dem Empfänger bekannt ist (z.B., wenn das Anfangspaar von übertragenen Signalen vorgegeben wird). Solch eine Ausführungsform ist in 2 gezeigt, wo der Maximum-Likelihood-Detektor 27 einzig dem Kombinierer 26 antwortet. (Elemente in 3, die mit Bezugszeichen versehen sind, welche mit den Bezugszeichen aus 1 übereinstimmen, sind entsprechende Elemente.) Der Kombinator 26 des Empfängers 30 entwickelt die Signale

entwickelt dann die Zwischensignale A und BIn the embodiment described above, each block of symbols is represented as a block using the channel estimates

and

recovered. However, other approaches for recovering the transmitted signals can also be used. In fact, there is an embodiment for transmitted symbol recovery in which the channel transmission functions need not be determined at all, provided that an initial pair of transmitted signals is known to the receiver (e.g., if the initial pair of transmitted signals is predetermined). Such an embodiment is shown in 2 shown where the maximum likelihood detector 27 only the combiner 26 responds. (Elements in 3 which are provided with reference numerals, which with the reference numerals 1 match, are corresponding elements.) The combiner 26 Recipient 30 develops the signals

then develops intermediate signals A and B

wobei N₃ und N₄ Rauschtherme sind. Es kann angemerkt werden, dass das Signal r₂ tatsächlich r₂ = h₀ŝ₂ + h₁ŝ₃ = h₀s₂ + h₁s₃ + n₂ ist und in ähnlicher Weise für Signal r₃. Da die Verarbeitung der Signale A und B sie auch gleichsetzt

wobei N₁ und N₂ Rauschtherme sind, folgt, dass die Signale s₂ und s₃ gleich sind

Wenn die Leistung aller Signale konstant (und auf 1 normalisiert) ist, reduziert sich die Gleichung (15) zuand finally develops the signals

where N ₃ and N _{4 are} noise sources. It can be noted that signal r _{2 is} actually r ₂ = h ₀ ŝ ₂ + h ₁ ŝ ₃ = h ₀ s ₂ + h ₁ s ₃ + n ₂ and similarly for signal r ₃ . Since the processing of signals A and B also equates them

where N ₁ and N _{2 are} noise sources, it follows that the signals s ₂ and s _{3 are the} same

If the power of all signals is constant (and normalized to 1), equation (15) reduces

und

tatsächlich Abschätzungen der Signale s₂ und s₃ innerhalb eines multiplikativen Faktors). Die Linien 28 und 29 zeigen den rekursiven Aspekt der Gleichung (13), bei der Signalabschätzungen

und

mit Hilfe der rückgewonnenen Signale s₀ und s₁, die von dem Ausgang des Maximum-Likelihood-Detektors rückgekoppelt werden, ausgewertet werden.Hence the signals

and

actually estimates of the signals s ₂ and s ₃ within a multiplicative factor). The lines 28 and 29 show the recursive aspect of equation (13), in which signal estimates

and

evaluated using the recovered signals s ₀ and s ₁ , which are fed back from the output of the maximum likelihood detector.

und

werden an den Maximum-Likelihood-Detektor 24 angelegt, wo die Wiedergewinnung mit dem Maßstab, der durch obige Gleichung (10) ausgedrückt ist, erreicht wird. Wie in 2 gezeigt, werden, wenn die Signale s₂ und s₃ rückgewonnen sind, diese zusammen mit den empfangenen Signalen r₂,r₃,r₄ und r₅ dazu verwendet, die Signale s₄ und s₅ rückzugewinnen und der Prozess wiederholt sich.The signals

and

are connected to the maximum likelihood detector 24 where recovery is achieved with the scale expressed by equation (10) above. As in 2 shown, when the signals s ₂ and s _{3 are} recovered, these are used together with the received signals r ₂ , r ₃ , r ₄ and r ₅ to recover the signals s ₄ and s ₅ and the process repeats itself.

und legt diese Abschätzungen an den Kombinator 23 und an den Detektor 42 an. Der Detektor 24 gewinnt die Signale s₂ und s₃ wieder, in dem er die Vorgehensweise verwendet, die von dem Detektor 24 der 1 benützt wird, ausgenommen, dass er nicht die Vereinfachung der Gleichung (9) verwendet. Die rückgewonnenen Signale des Detektors 42 werden an den Kanalabschätzer 43 rückgekoppelt, der die Kanalabschätzungen als Vorbereitung für den nächsten Zyklus aktualisiert. 3 illustrates an embodiment that does not require the constellation of the transmitted signals to include symbols of equal power (elements in 3 which are provided with the same reference numerals as in 1 , are similar elements.) In 3 the channel estimator replies 43 Recipient 40 on the output signals of the maximum likelihood detector 42 , If the channel estimator 43 Having access to the recovered signals s ₀ and s ₁ , it forms the estimates

and submit these estimates to the combiner 23 and to the detector 42 on. The detector 24 wins the signals s ₂ and s ₃ again using the procedure used by the detector 24 the 1 is used, except that it does not use the simplification of equation (9). The recovered signals from the detector 42 are to the channel estimator 43 fed back, which updates the channel estimates in preparation for the next cycle.

The embodiments of the 1 to 3 explain the principles of this invention for arrangements that have two transmit antennas and one receive antenna. However, these principles are broad enough to include a variety of transmit antennas and a variety of receive antennas. To illustrate this, shows 4 an embodiment in which two transmitting antennas and two receiving antennas are used; the transmit antennas are included 31 and 32 , and the receiving antennas with 51 and 52 designated. The signal from antenna 51 is received is sent to the channel estimator 53 and the combiner 55 laid out, and the signal from antenna 52 is received is sent to the channel estimator 54 and the combiner 55 created. Estimates of the channel transfer functions h ₀ and h ₁ are made by the channel estimator 53 to the combiner 55 and to the maximum likelihood detector 56 created. Similarly, channel transfer functions h ₂ and h ₃ are estimated by the channel estimator 54 to the combiner 55 and to the maximum likelihood detector 56 created. Table 2 defines the channels between the transmitting antennas and the receiving antennas, and Table 3 defines the impression of the signals received at the two receiving antennas.

Table 2

Table 3

wobei n₀, n₁, n₂ und n₃ komplexe Zufallsvariable sind, die thermisches Rauschen, Störungen und dergleichen am Empfänger repräsentieren.Based on the above, it can be shown that the received signals are

where n ₀ , n ₁ , n ₂ and n _{3 are} complex random variables that represent thermal noise, interference and the like at the receiver.

Setzt man die jeweiligen Gleichungen ein, erhält man

wodurch gezeigt wird, dass die Signale

und

tatsächlich Abschätzungen der Signale s₀ und s₁ sind. Entsprechend werden die Signale

und

an den Maximum-Likelihood- Decodierer 56 gesendet, der die Entscheidungsregel der Gleichung (10) dazu verwendet, die Signale ŝ₀ und ŝ₁ rückzugewinnen.In the order of 4 developed the combiner 55 the following two signals sent to the maximum likelihood detector:

If you use the respective equations, you get

which shows that the signals

and

are actually estimates of the signals s ₀ and s ₁ . The signals are corresponding

and

to the maximum likelihood decoder 56 sent, which uses the decision rule of equation (10) to recover the signals und ₀ and ŝ ₁ .

How As shown above, the principles of this invention are based on the fact that the broadcaster a diversity in the signals from the receiver are received, enforced, and that diversity is different Way can be achieved. The exemplary embodiments are based on spatial diversity - evoked through a variety of transmit antennas, and a time diversity by using two time intervals for the transmission of the encoded symbols. One should be aware that two are different Transmission frequencies are used instead of the two time intervals could. Such one embodiment would the transmission speed double but she would also increase the hardware expenditure in the receiver because two different ones Frequencies must be received and processed at the same time.

The explained above embodiments are obviously only exemplary implementations of the principles of the invention and various modifications and extensions can introduced to a specialist without departing from the spirit and scope of this invention to deviate, which is defined by the following claims are. For example, all of the embodiments shown were for choice a space-time diversity explains but as explained above could one can also choose the room-frequency pair. Such a choice would be have a direct impact on the design of the receiver.

Claims (33)

A wireless signal transmitter, the transmitter receiving incoming signals and the incoming signals being blocks of symbols, the transmitter comprising: an encoder that encodes incoming signals, the encoding including negation and complex conjugation of selected symbols; and a plurality of antennas for transmitting the encoded signals, the plurality of antennas providing spatial diversity in the transmitted signals, and the transmitter providing another type of diversity in the transmitted signal selected from a group comprising time diversity and frequency diversity; wherein the encoder encodes incoming signals in blocks of n symbols and wherein, if n = 2, the encoder converts an incoming block of symbols s ₀ and s ₁ into a first symbol sequence s ₀ and s ₁ and into a second symbol sequence -s ₁ * and encodes s ₀ *, where s _j * is the complex conjugate of s _j . The transmitter of claim 1, wherein the symbols transmitted have the same energy. The transmitter of claim 1, wherein the transmitter is the first Sequence of symbols above transmits one of the plurality of antennas and the second symbol sequence via one transmits others from the variety of antennas. A receiver for receiving signals, comprising: a combiner for combining at least two non-noise signals received from an antenna to develop sets of information symbol estimates, the combiner being responsive to channel estimates developed for at least two contiguous spatial paths, via which the at least two non-noise signals arrive at the antenna and the combiner develops the sets of information symbol estimates by combining the non-noise signals received from the antenna with the channel estimates of operations involving multiplications, negations and conjugations; and a detector connected to the combiner for developing maximum likelihood decisions conditions regarding the information symbols encoded in channel symbols and embedded in the non-noise signals received by the antenna, the detector being responsive to the sets of information estimates. receiver according to claim 4, further comprising a channel estimator, the responsive to the signals received by the antenna for development the channel estimates, being the channel estimator the channel estimates developed when the signals received by the antenna are known Include sequence. receiver according to claim 4, further comprising a channel estimator, the responsive to the signals received by the antenna for development the channel estimates. receiver according to claim 4, further comprising a channel estimator, the Essays of information symbols to estimate channel estimates. receiver according to claim 4, further comprising a channel estimator, the responsive to detector output signals, for estimating and Develop channel estimates. Transmitter for wireless communication, including: an encoder, the incoming Data in blocks receives from n symbols, wherein the encoder generates encoded symbol strings and wherein the generating the selective complex conjugation of symbols and the selective negative includes complex conjugation of symbols; and at least two Transmitting antennas for transmitting the coded symbol sequences with spatial diversity, where each of the at least two transmit antennas is coded differently Sequence sends, and wherein the transmitter another based on time diversity or frequency diversity diversity in the transmitted coded sequences. The transmitter of claim 9, wherein n = 2 and wherein the at least two transmit antennas comprise a first transmit antenna and a second transmit antenna and, in response to a sequence {s ₀ , s ₁ , ...} of the symbols arriving, a sequence {s ₀ , s ₁ , ...}, which is applied to the first transmission antenna, and a sequence {–s ₁ *, s ₀ *, ...} is developed, which is applied to the second transmission antenna, where s ₁ * is the complex conjugate of s, is. The transmitter of claim 9, wherein the symbols are symbols with the same energy. The transmitter of claim 9, wherein the transmit antennas Comprise K transmission antennas for realizing K different channels, where n · m Symbols on the K antennas above L time intervals are distributed, where K = m and L = n or K = n and L = m. The transmitter of claim 9, wherein the at least two Transmitting antennas K transmitting antennas for realizing K different channels include, where n · m Symbols on the K antennas above L frequencies are distributed, where K = m and L = n or K = n and L = m. Transmitter for wireless communication, including: an encoder, the incoming Data in blocks received from n data bits and encoded symbol sequences and wherein the encoder is unchanged and changed symbol streams generated from the incoming data, the changed symbol stream some symbols in complex-conjugated form and some symbols in contains negated and complex-conjugated form; and an output unit to output the unchanged Symbol stream to at least a first transmission antenna and for output of the changed Symbol stream to at least one second transmission antenna to provide space diversity, wherein each of the at least first and second transmit antennas has one differently coded sequence and where the transmitter sends a further diversity in the transmitted coded sequences based on time diversity or frequency diversity. The transmitter of claim 14, wherein the symbols are symbols same energy. The transmitter of claim 14, wherein the at least first and second transmit antennas K transmit antennas for realizing K different channels include, where n · m Symbols on the K antennas above L. Time intervals are distributed and where K = m and L = n or K = n and L = m. The transmitter of claim 14, wherein the at least first and second transmit antennas K transmit antennas for realizing K different channels include, where n · m Symbols on the K antennas above L. Frequencies are distributed and where K = m and L = n or K = n and L = m. Transmitter for wireless communication, including: an encoder on incoming symbols addresses, the encoder from the incoming Symbols a first block of output symbols and a second Block of output symbols, based on the first block of output symbols is generated, and wherein the first block of output symbols at least contains a first pair of symbols and wherein the second block of output symbols is at least a second Contains pair of symbols and wherein each symbol in the second block of parent symbols a complex conjugate or a negative complex conjugate one related symbol from the first block of source symbols is; a first transmit antenna connected to the encoder is, the first block of output symbols via the first transmission antenna is sent; and a second transmit antenna, using the encoder is connected, the second block of output symbols over the second transmission antenna is transmitted; and where the sender first block of output symbols via the first transmission antenna sends and the second block of output symbols over the second transmitter antenna to provide space diversity. The transmitter of claim 18, wherein a first symbol is sent in each of the symbol pairs at a time t and a second Symbol in each of the symbol pairs is sent at a time t + T, where T is about the same a symbol period. The transmitter of claim 18, wherein a second symbol in the second pair of symbols a complex conjugate of a first Is in the first pair of symbols. The transmitter of claim 18, wherein a first symbol in the second pair of symbols a negatively complex conjugate one second symbol in the first pair of symbols. The transmitter of claim 18, wherein the first and the second pair of symbols are symbol pairs of the same energy. receiver for wireless Communication, comprehensive: an antenna for receiving communication signals, wherein a first block of symbols over a first transmission path is received and with a second block of symbols over a second transmission path is received and the first transmission path is spatially different to the second transmission path is; and a decoder connected to the antenna the received signals respond, the decoder the first Block of symbols and the second block of symbols edited, to determine a received pair of symbols being the first Block of symbols contains at least a first pair of symbols and wherein the second block of symbols at least one second pair of symbols contains and wherein each symbol in the second block of symbols is a complex Conjugated or negatively complex conjugate of one assigned to it Symbol from the first block of symbols. receiver 24. The claim 23, wherein a first symbol in each of the symbol pairs is received at a time t and a second symbol each the pair of symbols is received at a time t + T. receiver 24. The claim 23, wherein a second symbol in the second pair of symbols a complex conjugate of a first symbol in the first pair of symbols is. receiver 24. The claim 23, wherein a first symbol in the second pair of symbols a negatively complex conjugate of a second symbol in the first Symbol pair is. receiver 24. The claim 23, wherein the first and second blocks of output symbols blocks same energy. receiver The claim of 23, wherein the decoder receives a maximum likelihood detector of the received signals. receiver 24. The decoder of claim 23, wherein the decoder comprises the first block of output symbols and processed the second block of output symbols to receive a received one Pair of symbols, by evaluating each symbol from the first Block of symbols with the associated symbol from the second Block of symbols to estimate. Transmitter for wireless communication, including: an encoder on incoming symbols addresses, the coding of the incoming Symbols creates a first block of output symbols and one generated second block of output symbols related to the first block of exit symbols, being each one of the output symbols in the first block of output symbols one of the output symbols in the second block of output symbols is related in the form of a symbol set and with one symbol in each Symbol set a complex conjugate or a negative complex conjugate to the other symbol in the symbol set; a first transmission antenna, which is connected to the encoder, the first block of output symbols via the first transmission antenna is transmitted; and a second transmitting antenna, which is connected to the encoder, the second block of output symbols via the second transmission antenna is transmitted; the second transmitting antenna spatial is different from the first antenna. The transmitter of claim 30, wherein one of the output symbols in each symbol set either with time diversity or with frequency diversity to its is sent in the output symbol assigned to the symbol set. The transmitter of claim 30, wherein a first symbol in each block of symbols at a time t and a second Symbol sent in each block of symbols at a time t + T where T is greater than Is zero. The transmitter of claim 30, wherein the first and the second block of output symbols are blocks of the same energy.