TW200935792A - Robust cyclic delay diversity scheme - Google Patents

Abstract

The invention relates to a transmitter, a transmission system, a transmission method and a computer program product enabling a robust Cyclic Delay Diversity (CDD) scheme for transmissions such as-but not restricted to-wireless transmissions. The robust CDD scheme can be achieved by inserting an artificial multipath channel in a transmitter chain before an actual transmission.

Description

200935792 IX. DESCRIPTION OF THE INVENTION: TECHNICAL FIELD OF THE INVENTION The present invention generally relates to a transmitter, a type of a strong cyclic delay diversity (CDD) architecture that can be enabled for transmission such as, but not limited to, wireless transmission. Transmission system, a transmission method, and a computer program product. [Prior Art] The wireless transmission system is almost ubiquitous today. For example, wireless local area networks (WLANs), cellular networks, and broadcast systems, which are defined, for example, in the IEEE 802.11-based standard, are widely used today. For such wireless transmission systems, the increase in the throughput of available channels is a major problem. A higher transmission amount can be obtained by using orthogonal frequency division multiplexing (〇FDM). In OFDM, a given system bandwidth is divided into a number of orthogonal subchannels, which are also referred to as subcarriers. Instead of transmitting data symbols continuously over a (very wide) channel, multiple data symbols are transmitted side by side. This results in a longer symbol length, so that the impact of inter-symbol interference (ISI) can be significantly reduced, so no additional means, such as expensive equalization, is required. One potential for further improving the performance of wireless transmission systems in terms of throughput and reliability lies in multi-antenna transmission techniques. Such techniques are used in, for example, multiple input multiple output (ΜΙΜΟ) antenna systems. These systems utilize multiple antennas at each transmitter and receiver. A plurality of channels can be established simultaneously between the transmitter and the receiver. As a result, the throughput can be increased and the bit error rate (BER) can be lowered. The ΜΙΜ〇 technology will be included, for example, in the future wlan standard IEEE 802.11 η, the future IEEE 8 〇 216 based microwave access 134798.doc 200935792 interworking (WiMAX) standard and future cellular network standards. The CDD is proposed for use in a multi-antenna transmission system to improve the transmission robustness, i.e., to improve the reliability of the transmission. CDD provides a concise method that provides transmit diversity while being backward compatible. The idea of cdd is to increase frequency selectivity and thus improve frequency diversity by simultaneously transmitting a cyclically delayed version of the time domain signal from different antennas. Fundamentally, it converts the spatial selectivity (diversity) of the antennas to frequency selectivity (diversity). The delays are done in a round-robin fashion so as not to extend the channel and more than one to ensure that the unique transmission does not interfere with another transmission. Protection Interval (GI). CDD can improve frequency selectivity by using channel coding. It has been included in the current draft of Qiuqiu 802.1 In and has been included, for example, in the next generation WLAN standard, WiMAX standard, hive. In the multi-antenna wireless system of the network standard and the broadcasting standard. In August 2006, IEEE Wireless Communication Journal, Vol. 5, No. 2, pp. 92_21, G. Bauch, J_S. Malik, Cyclic Delay Diversity with Bit Interleaved Code Modulation in Cross-Wave Multiple Access, discloses a CDD in a FDM system including an OFDM transmitter and an OFDM receiver. Such an OFDM transmitter and receiver will be Figure 5 is a block diagram of an OFDM transmitter using CDD in coded OFDM. The transmitter includes a forward error correction (FEC) encoder 50, an interleaver 5 1 (square "II") ,One Positive-parent amplitude modulation (qam)/phase shift keying (PSK) mapper 52 (square "QAM/PSK"), an inverse fast Fourier transform (IFFT) converter 53 (square "IFFT"), Ητ transfer branches 541 to 54ητ, ητ-1 cyclic shifters 552 to 55ητ (squares "δ2" to "Δητ"), leaves (1) plus 134798.doc 200935792 561 to 56ητ (square "GI" And ητ transmit antennas 571 to 57ητ. One receiver one receiving antenna 58 is shown in Fig. 5. Further, X, , ^, Α and X3 represent OFDM symbol samples, and ht(1) represents a ith transmit antenna 57i to the channel of the receiving antenna 58, Δ! represents a cyclic shift applied to the ith. transmitting antenna 57i. • The FEC encoder 50, the interleaver 51, the QAM/PSK mapper 52, and the IFFT The converters 53 are connected in series. Each of the ητ transmission branches 541 to 54nτ is connected to the IFFT converter 53 and includes a GI adder. The second to nthth transmission branches 542 to 54nτ respectively include a placement a loop shifter before the GI adder. The first transition branch 541 does not contain a cyclic shifter, since the cyclic shift applied to the first transmitting antenna 517 can be set to zero without loss of generality. Each of the transmitting antennas 571 to 57nτ is connected to the ητ One of the transfer branches 541 to 54nτ transmits the branch accordingly. An input data stream is encoded in the FEC encoder 5, interleaved by the interleaver 51 Φ, mapped by the QAM/PSK mapper 52, and converted from the frequency domain to the time domain by the IFFT converter 53. One of the obtained OFDM signals is carried on each of the ητ transmission branches 541 to 54nτ. In each of the second to nthth transfer branches 542 to 541^, the respective cyclic shifters cyclically move the number of the respective 〇fdm signals carried on the transfer as a branch. The first transfer branch 541 is shipped. Each of the GI adders 561 through 5611 adds a called cyclic prefix (cp) to the signal carried on the transport branch of the respective GI adder of the packet 3u. More specifically, the GI adders (6) insert a GI between the 134798.doc 200935792 of the 〇FDM symbol. The OFDM signals generated by the respective GIs are transmitted to the receiving antenna 58 via a channel between the respective transmitting antennas and the receiving antenna 58. With the above transmitter, as shown in Fig. 5, each transmitting antenna transmits a cyclically shifted version of the same OFDM symbol. In this way, a previously proposed CDD architecture included in the current draft of IEEE 802.1 1 η is implemented. Figure 6 is a block diagram of an OFDM receiver for receiving signals from a transmitter as shown in Figure 5. The receiver includes a receiving antenna 60, a GI remover 61 (crossed square "GI"), a fast Fourier transform (FFT) converter 62 (square "FFT"), a QAM/PSK solution A mapper 63, a deinterleaver 64 (block "ΙΓ1"), and an FEC decoder 65. These components are connected in series. An OFDM signal transmitted by a transmitter as shown in Fig. 5 via a channel from the transmitting antenna to the receiving antenna 60 is received by the receiver. The GI remover 61 removes the GI from the received OFDM signals. The resulting signal is converted by the FFT converter 62 from the time domain to the frequency domain, demapped by the QAM/PSK demapper 63, deinterleaved by the deinterleaver 64, and decoded by the FEC decoder 65. The previously proposed CDD architecture, such as the CDD architecture implemented, for example, with the transmitter shown in Figure 5 and included in the current draft of IEEE 802.11n, is based on spatial diversity (selectivity) to increase the frequency selectivity. For OFDM multi-antenna transmission systems, CDD can be an effective way to increase the frequency selectivity of the channel and increase the robustness of the system. 134798.doc 200935792 The channel becomes more frequency selective due to the artificially increased channel length. Therefore, the error correction code can select a more reliable symbol and such a strong increase. ❹ ❹ However, if the environment of a multi-antenna transmission system is not strongly scattered and/or there is a line of sight (L〇s) between a transmitter and a receiver, ie, the stronger L〇s component, from different The channels that transmit antennas to the (etc.) receive antennas will be highly correlated. In other words, the channels that each antenna will experience will be highly correlated, and the spatial diversity (selectivity) will be greatly limited. In this case, applying the previously proposed (:1) architecture makes a subset of subcarriers ineffective and performance will be worse than a single antenna transmission system. In the extreme case where a single LOS component of each antenna and the same channel are identical, the previously proposed (10) architecture will result in invalidation of odd subcarriers while doubling the channel gain of even subcarriers. In this case, half of the transmitted data symbols are lost. 'The channel code may not recover these missing data symbols. The graph of Figure 7 shows a combined channel frequency response of a 传送Cong transmitter as shown in Figure 5, an OFDM receiver as shown and a coffee channel with two transmitting antennas. The horizontal axis represents the 0th to the (Ns, subcarriers) in a subcarrier 1 transmitted by a buffer. The vertical axis represents the value of a channel transmission function. The value is _丨. The false (four) is highly correlated from each transmitting antenna. To the channel of the receiving antenna, an example of a LOS condition with a relatively radio environment, a Shigger column, a transmission antenna Nt=2, and a Δs_=Ns/2 displacement are displayed. The combined channel frequency (4) of the two antennas in the previously proposed cDD architecture should be shown to be an odd number of subcarriers from the table. This means that the subcarriers are 134798.doc 200935792 The subset is completely ineffective. This results in a performance degradation due to this invalid effect of the CDD architecture. Ideally to prevent such performance degradation due to the high correlation between the antennas in LOS or highly correlated antenna situations. While maintaining the advantages of CDD in a strong scattering environment, it is desirable to provide a frequency that avoids this degradation in LOS and/or poor scattering while maintaining the increased frequency in a strong scattering environment. Selective strong CDD shelf .

SUMMARY OF THE INVENTION One object of the present invention is to provide a robust CDD architecture that mitigates at least some of the above disadvantages of the previously proposed CDD architecture. This object is achieved by a transmitter as in the first aspect and a transmission method as in the technical scheme 19. In a first aspect of the present invention, a transmitter includes a plurality of transmission branches each configured with a transport-signal, and at least one processor configured to be processed by a separate multi-channel, at least In a second aspect of the invention, a signal on a transmission branch of a plurality of transmission branches and a complex number = knife configuration to output a signal provided by the corresponding transmission branch, according to the first a transmitter and at least one receiver in the present invention _

The method of transporting the Hi-transmission on the branch is comprised of a plurality of 'one less; processing the signal and output of the I 134798.doc 200935792 on at least one of the plurality of transmission branches by means of a separate multipath channel - The signal provided by the corresponding transmission branch. In the fourth aspect of the present invention, the computer program port for the computer includes a software code portion. When the product is run on a computer, the software code portion is used to execute a software according to the present invention. The third aspect of the method - these steps. The first to fourth aspects, such as βH, can increase the spatial diversity (spatial selectivity). The result is that the CDD architecture to be applied will result in a frequency selective channel even in L〇s and poor ❹t-shooting environments. Therefore, the transmission is robust to any environment and does not suffer from problems in L〇s and poorly scattered environments due to CDD. Therefore a strong (:1)] architecture can be provided. Other advantageous modifications will be defined in the request items. These and other aspects of the invention will be apparent from the embodiments described hereinafter and illustrated by the embodiments. [Embodiment] A first embodiment of the present invention will be described below. 1 is a block diagram of an exemplary transmitter having a multipath channel using a CDD architecture in accordance with the first embodiment of the present invention. The transmitter can be an ofdm transmitter using the code &fe>M. It may include an encoder such as an FEC encoder 1 , an interleaver 11 (block "Π"), a mapper 12 such as a QAM/PSK mapper (square "QAM/PSK"), a converter For example, an IFFT converter ι3 (square "IFFT"), ητ transfer branches (4) to 14ητ, ητ] cyclic shifters ι52 to 15ητ (squares Δ2" to ''ΔηΤ,), nHgiGi adders 161 to 16 Ητ (squares "GI"), ητ (manual) multipath channels (tap-type delay line filters or tapped delay lines) acting as processors (processing mechanisms) 171 to 17ητ (square "w! ( t) to 134798.doc •11- 200935792, ηΤ(1)") and shame transmitting antennas 181 to 18ητ serving as outputs. One of the receivers, an exemplary receive antenna, is shown in Figure 〖. Further, %, 孓, 毛, and & represent data symbol samples, ht(1) represents a channel from the second transmitting antenna 18i to the receiving antenna 19, and Δι represents a signal applied to the second transmitting antenna 18i. Cyclic displacement. • The FEC encoder 10 can encode an input data stream and output a result. The interleaver 11 can interleave the input provided by the FEC encoder 1 and output a result. The QAM/pSK mapper 12 maps an input provided by the interleaver u and outputs a result. The IFFT converter 13 converts an input provided by the QAM/PSK mapper 12 from the frequency domain to the time domain and outputs a result. A signal provided by converter 13 can be carried on each of said ητ transfer branches 141 to 14nτ. In each of the second to shame transfer branches 142 to 14nτ, the individual cyclic shifter can cyclically move a data symbol of the individual signal carried on the transfer branch, the first transfer branch 141 not A cyclic shifter is included because a cyclic shift applied to the first output 丨 81 can be set to zero without loss of generality. Therefore, the original signal can be carried on the first transfer branch 141 without performing a cyclic shift. The ith GI adder 16i may add a GI (CP) to a one of the first transfer branches 14i that is carried by the i-th cyclic shifter 15 or provided by the IFFT converter 13. In the signal, a cyclic shift does not occur as in the case of the first transfer branch 141. More specifically, each of the (1) adders 161 to 16nτ can insert a GI between the data symbols of the individual signals. A result can be output. Each of these processors! 7丨 to 丨7ητ can be used 134798.doc •12- 200935792 The time domain signal provided by the corresponding GI adder. More specifically, this time domain signal can be used with individual artificial multipath " linear convolution. Therefore, each of these ", delay lines" ox 71 to Ρητ can be considered as a linear convolution of the two (four) (Ai) multiple (four) tracks (tap-type delay lines). For 5, - is carried - The signal on the heart transfer branch (4)

删 The deletion number can be cyclically moved in a first step, such as with the previously proposed CDD architecture. In a second step prior to transmission, the signal generated by the cyclic shift can be linearly convolved with a heart-to-heart (short) artificial multipath channel (tap-type delay line with random or pseudo-random weights, ie %(1)). a sister fruit can be provided to the output (8) of the transmitter. In the case where the heart (four) W is a transmitting antenna, the signal supplied can be received via the ith transmitting antenna 18i and the receiving A channel between the antennas 19 is transmitted to the receiving antenna 19. Fig. 2 is an exemplary artificial multipath channel (tap-type delay line) for a second transmission branch of a transmitter according to the first embodiment. Block diagram of the structure. As shown in Figure 2, a block like "*" Wi(t)" (where 1 = 1, 2, ..., ητ) can be equal to one including L-1 delays 2〇2 to 2〇L, L multipliers 211 to 21L and a tap delay line of an adder 22. An input signal can be transmitted via all of the delays 202 to 20L. After each delay, a delay is used And all previous delay delay signals can be tapped and provided to a different multiplier. After the first delay 2 〇 2, a signal delayed by the first delay 202 can be tapped and supplied to the second multiplier 212, after the second delay 203, by the first delay The signal delayed by 202 and the second delay 203 can be tapped and supplied to the 134798.doc -13 - 200935792 three multiplier 213, and so on. After the (L-1)th delay 20L, A signal delayed by all of the L-1 delays can be supplied to the Lth multiplier 21L. Further, before the first delay 202, a signal can be tapped and provided to the first Multiplier 211, where this signal is not delayed 'because there is no delay in front of this case. Each multiplier. 21] (where j = 1, 2, ..., L) can be supplied to the multiplier The signal is multiplied by a random or pseudo-random weight Wij and a result is output. The results from all of the multipliers 211 to 21L can be provided to the adder 22. The adder 22 can input the inputs provided by the multipliers 211 to 21L. Add and output a result number. This signal is the number of input signals with multiple gains. According to this first embodiment, an artificial multipath channel (tap-type delay line) can be inserted into each of the transmission branches together with the CDD in the transmitter link before an actual transmission. The tapped delay lines applied to the respective outputs can be different from each other. Therefore, the individual outputs of the transmitter can be provided with a different artificial φ channel. Therefore, each output can withstand a different short channel, resulting in a lower correlation. Channel frequency response. Since the channel frequency response is less correlated, the CDD architecture applied to the transmitter will not invalidate the subcarriers as frequently as the previously proposed CDD architecture, while a higher frequency selection Sex can still be maintained. With this architecture, the CDD applied to these outputs will have no invalid effect in the LOS case, and the advantages of cDD in a strong scattering environment can be maintained. With this first embodiment, the artificial multipath channel (tap-type delay line) can be applied after the GI (CP) insertion. Therefore, it will extend the channel. Therefore, 134798.doc •14· 200935792 The length of the tapped delay line can be chosen to be shorter so as not to exceed the length. A second embodiment of the present invention will be described below. 3 is a block diagram of an exemplary transmitter having a multipath channel using a CDD architecture in accordance with a second embodiment. The transmitter can be an OFDM transmitter using coded OFDM. It may include an FEC encoder 30, an interleaver 31 (square "II"), a mapper 32 such as a QAM/PSK mapper (square "QAM/PSK"), an IFFT converter 33 (square &quot ;IFFT"), ητ transfer branches 341 to 34ητ, 〇ητ-1 cyclic shifters 352 to 35ητ (square "Δ/to"ΔηΤ"), ητ have (manual) multipath channels (tap delay A loop (circular) convolver 371 to 37ητ (block Wi(t) to "wnT(t)"), ητ GI force acting as a processor (processing mechanism) of a line filter or a tapped delay line) The π-methods 361 to 36ητ (squares "GI") and ητ transmit antennas 3 8 1 to 3 8ητ serving as outputs. One of the receivers, an exemplary receiving antenna 39, is shown in Fig. 3. In addition, &; texts 2 and 3 represent data symbol samples, and ht(1) represents a channel from the i-th transmitting antenna 38i to the receiving antenna 39, representing a cyclic shift applied to the i-th transmitting antenna 38i. The encoder 3 can encode an input data stream and output a result. The interleaver 31 can be interleaved by the FEC. The encoder provides an input and outputs a result. The QAM/PSK mapper 32 maps an input provided by the interleaver 31 and outputs a result. The IFFT converter 33 can map a QAM/PSK. The input provided by the unit 32 is converted from the frequency domain to the time domain and outputs a result. A signal provided by the 11?1 converter 33 can be carried on each of the ητ transmission branches 341 to 34ητ. The second to the first 134798.doc -15- 200935792 movement is transported ί=34ηΓ, the respective cyclic shifter can send the data symbols of the respective signals on the branch. The: ί: contains a cyclic displacement Since - is applied to the cyclic displacement Δ of the two c, the original signal can be carried on the first transfer branch 341 without performing a cyclic shift without loss of generality. ❹ ❹ A processor 37i can process a message that is carried on the first transmission component % and is provided by the ith cycle shifter (5) or is provided by the request converter 33 in the case of the first transmission bit 341^ __cyclic displacement: time domain apostrophe. More specifically, the respective The domain signals can be cyclically (circular) convolved with the respective artificial multipath channels (tap-type delay lines). A result can be output. In other words, a data symbol that is carried on a second transmission branch (10) Can be cyclically moved in the -step, as in the previously proposed CDD architecture. In the second step prior to the GI insertion and the transmission, the signal generated by the cyclic shift can be used by a third person. The path channel (tap-type delay line) is convolved with a random or pseudo-random weight, ie wi=[WilWi2Wi3".WiL]) loop (ring). A circular (circular) convolution with the artificial multipath channel (tap extension) %=[^ Wi,2 Wi,3 .. '(10) block symbol vector> name, ",...,'] The output of cc) will be nj - Z^^W, · („_m)mod ^, 0 < « < iV - 1 m=0 A VII, ~ .. The ith CH adder 36i can be - Gl(cp) is added to a signal provided by the & processor 37i. More specifically, each m adder is added to 36nτ to insert a 〇1 between the data symbols of the respective signals. 134798.doc -16· 200935792 is provided to the ith output 38i of the transmitter. Where the output yang is a transmit antenna, the signal is provided via a ith transmit antenna A channel between the 38i and the receiving antenna 39 is transmitted to the receiving antenna 39. According to the second embodiment, an artificial multipath channel (tap-type delay line) can be used with the transmitter before an actual transmission. The CDD in the link is inserted into each of the transfer branches. The tapped delay lines applied to the respective outputs can be different from each other. Therefore, the respective outputs of the transmitter A different artificial channel is provided. Therefore, each output can withstand a different short channel, resulting in a lower correlation channel frequency response "The CDD architecture applied to the transmitter due to the lower correlation of the channel frequency response. The subcarriers will not be inactive as frequently as the previously proposed CDD architecture, while a higher frequency selectivity can still be maintained. With this architecture, the cdd applied to these outputs will not be invalid in the LOS case. The effect, at the same time (: the advantage of 〇〇 in a strong scattering environment can be maintained. Φ With this second embodiment, the artificial multipath channel (tap-type delay line) can be applied before the GI (CP) insertion. Therefore, the loop (circular) convolution. Non-linear convolution can be implemented. This architecture will have a similar effect to CDD. In addition, it does not affect the ISI problem at all, so the tap delay The length can be selected without regard to the length of the GI. This means that the length of the tapped delay line can be longer compared to the first embodiment, while still avoiding the ISI effect. It is described above and is shown in The configurations in Figures 1 and 3 are merely examples of the transmitters according to the first and second embodiments. The configurations are only 134798.doc • 17-200935792 and are exemplary and not limiting. In this case, even though Figure 3 and Figure 3 show that each transfer branch contains one processor, fewer processors or even just one processor is sufficient to provide a robust advantage. In addition, several are configured to handle multiple Processors that transmit multiple signals on the branch can be used. Additionally, fewer guard interval adders and/or cyclic shifters are possible than shown in Figures i and 3. Further, even if only one receiving antenna is shown in Fig. 3, a plurality of receiving antennas are possible. meaning

❹ That is, the transmission system of the transmitter according to the first or second embodiment may be, for example, a Home Input Single Output (MISO) system or a MIMO system. In addition, other mappers other than the non-QAM/PSK mapper can be deprecated. For example, an ASK mapper can be used. Other modifications such as those assigned by the error (square "II") are also conceivable. The above CDD architectures according to the first and second embodiments can be used in OFDM or a single carrier system with CP. They can also be used in other types of transmission systems that enable multi-input transmission, such as system execution MIM or smart technology. The transmitter according to the first and second embodiments may be part of a transmission system comprising at least one transmitter and at least one receiver. A receiver can be configured, for example, as shown by circle 6, wherein the receiver can include a single input or receive antenna or multiple input or receive antennas as in Fig. 6. Each of the transport H and receiver can be, for example, a 岐 or a portable terminal device. For example, each of the transmitters and the receivers may be a WLAN or user equipment such as a data machine, a data card, etc. for enabling access to a 134798.doc • 18· 200935792 WLAN and having such a data machine, An access point for a fixed computer or laptop that has the ability to access a WLAN, such as a data card. Other examples include a base station or broadcast station of a cellular network and user equipment such as a mobile phone or a fixed or portable television. The transmission system can be, for example, a WLAN, a cellular network or a broadcast system. The above functions of the first and second embodiments can be implemented by a transmission method. When the computer program product runs on the computer, the steps of the method can be performed by a software code portion of a computer program product for a computer. Figure 4 is a flow chart showing the basic steps of an exemplary transfer method in accordance with the first and second embodiments. In step 31 the signal is carried on a plurality of transport branches. At least one of the signals carried on at least one of the plurality of transport branches in step S2 is processed by a respective multipath channel. A signal supplied by a corresponding transfer branch is output in step S3. With the coffee architecture according to the first and second embodiments, the spatial diversity (spatial selectivity) can be improved. Therefore, the CDD architecture used will result in - even frequency selective 胄 in L0S and poor scattering environments, so 'transmission is solid for any environment, and because CDD^ will not suffer L〇s and any problems in the poor scattering environment. The robust CDD architectures proposed in accordance with the first and second embodiments are particularly useful for channels with reduced frequency/less frequency selectivity. They can: take advantage of the rising frequency selectivity that can be achieved with the previously proposed CDD architecture, avoiding the ineffective effects of such architectures in highly correlated channels and significantly increasing the length of the channel. 134798.doc -19· 200935792 With the CDD architectures according to the first and second embodiments, there is no need for information about the channel. Furthermore, the signal does not need to be processed in this spatial domain. There is also no need for beamforming. In addition, there is no maximum limit to the length of the CDD that can be applied. There may be only a maximum limit on the number of taps on the tap delay line to avoid the 1SI effect. Even such a tap limit does not exist in this first embodiment because a cc instead of a linear convolution is applied to this embodiment.

The first and second embodiments described above provide alternative constructions for the (:£>1) architecture. Compared to the previously proposed CDD architecture for multi-antenna transmission systems, such as the CDD architecture included in the current draft of IEEE 8〇2 Un, they are able to avoid performance degradation in LQS and/or poor scattering environments, while improving The frequency selectivity of the strong scattering environment t. The invention can be used to transmit a pure transmission system such as a wlan, a ΜΜΑΧ system, a cellular network and a broadcasting system such as a digital television (DTV) based on the future IEEE 8G2.Un standard, in particular, the implementation of the system is 10 or The technical τ-generation wireless system and standards are particularly interesting. The invention is described and illustrated in detail in the drawings and the foregoing description. The invention is not limited to the specifically disclosed embodiments. Based on the description of the drawings, the description and the trainee understandable and ώ%1# 咕, the technical familiarity includes the modification of the embodiment. In the request item, the words include other components that are not excluded. , a number of components or steps... a single reopening of his saponins can achieve multiple columns I34798.doc •20· 200935792 The functions of the request items in these claims are listed in different Attached

The fact that the method of Μ does not mean that one of these methods cannot be used to brake, the β-computer program can be stored/distributed on a suitable body, for example, the optical storage medium body of the spot or As part of other hardware, you can... Media or - Solid media, can also be distributed in other forms, in the Internet or other wired or wireless communications. These request items: the material involved in the b-sew is understood as (4) the limit of money. In summary, the present invention relates to a -= transmitter delivery system, a transmission method, and a computer program that can enable a strong cyclic delay diversity (CDD) architecture for transmission such as, but not limited to, wireless transmission. The CDD architecture can be implemented by inserting a manual multipath channel into a transmitter link prior to actual transmission. BRIEF DESCRIPTION OF THE DRAWINGS The present invention is described with respect to embodiments with reference to the accompanying drawings in which: FIG. 1 is a block diagram of an exemplary transmitter having a multi-path channel using a CDD architecture in accordance with a first embodiment; 2 is a block diagram of a configuration of an exemplary multipath channel for a second transmission branch of a transmitter according to the first embodiment; FIG. 3 is a block diagram of a cDD architecture according to a second embodiment. A block diagram of an exemplary transmitter of a multipath channel; FIG. 4 is a flow chart of the basic steps of an exemplary transmission method according to one of the first and second embodiments; FIG. 5 is a diagram of using CDD in coded OFDM A block diagram of an OFDM transmitter; 134798.doc -21 - 200935792 Figure 6 is a block diagram of an OFDM receiver; and Figure 7 is a graph of a combined channel frequency response for a LOS with two antennas. [Main component symbol description]

10 F Ε C code 11 interleaver 12 mapper 13 IFFT converter 14 η, 传送 transfer branch 1 5ητ cyclic shifter 16ητ GI adder 1 7ητ processor 1 8 传送 transmit antenna 19 receive antenna 20L delay 21L multiplier 22 addition 30 FEC encoder 31 interleaver 32 mapper 33 IFFT converter 34ηχ transmission branch 3 5ητ cyclic shifter 3 6ητ GI adder 134798.doc -22· 200935792

37ητ processor 3 8ητ transmitting antenna 39 receiving antenna 50 FEC encoder 51 interleaver 52 mapper 53 IFFT converter 54ητ transmitting branch 55ητ cyclic shifter 56ητ GI adder 58 receiving antenna 60 receiving antenna 61 GI remover 62 FFT converter 63 Demapper 64 Deinterleaver 65 FEC Decoder 141 Transfer Branch 142 Transfer Branch 152 Loop Displacer 161 GI Adder 162 GI Adder 171 Processor 172 Processor 134798.doc -23- 200935792 ❹ 134 134798.doc 181 Transfer Antenna 182 Transmit Antenna 202 Delay 203 Delay 211 Multiplier 212 Multiplier 341 Transfer Branch 342 Transfer Branch 352 Cycle Displacer 361 GI Adder 362 GI Adder 371 Processor 372 Processor 381 Transfer Antenna 382 Transmit Antenna 541 Transfer Branch 542 Transfer branch 552 Cycle shifter 561 GI adder 562 GI adder 571 Transfer antenna 572 Transfer antenna 573 Transfer antenna S1 Transport ioc -24- 200935792 S2 Process S3 output❹

134798.doc -25-

Claims (1)

200935792, the scope of patent application: 1. 传送 A transmitter comprising: a plurality of transmission branches (141, 142, ..., 14nτ; 341, 342, ..., 34n) respectively configured to carry a signal At least one processor configured to process at least one signal carried on at least one of the plurality of transfer branches by means of a respective multipath channel (171, m, ..., 17nτ; 371, 372, . . . 37nτ); and a plurality of outputs (181, 182, ..., 18nτ; 381, 382, ..., 3 8Πχ; 3812.) respectively configured to output a signal provided by a corresponding transfer branch. The transmitter of item 1, wherein the respective multipath channels are an artificial multipath channel. 3. The transmitter of claim 1, wherein the respective multipath channel is a tapped delay line. 4. The transmitter of claim 3, wherein the tapped delay line comprises: a plurality of delays (202, 203, ..., 20L) respectively configured to delay a signal within the delay line; Configuring to use a weight (wn) after one of the plurality of delays or after one of the first to (L-1)th delays of the plurality of delays , wi2, ..., WiL) multipliers (211, 212, ..., 21L) multiplied by a signal tapped from the delay line; and a plurality of signals configured to be provided by the plurality of multipliers Add 134798.doc 200935792 Adder (22). Wherein the weight is a random or pseudo-random weight 5. The transmitter of request item 4 is 7. 7. If the request item is transmitted, the benefit is generated, wherein the at least one processor is placed in the less-transfer branch . A transfer of claim 1 11 'where the transfer H includes a separate branch with each transfer branch is placed in a corresponding transfer branch. 8. The transmitter of claim 1 further comprising: a number of data configured to cyclically move the at least one signal: a #ring shifter (152, ..., 15nτ; 352, ..., 35nτ) And wherein the at least one processor is configured to process the data symbols moved by the at least one cyclic shifter. 9. The transmitter of claim 8, wherein the transmitter includes a circular shifter in each of the plurality of transfer branches except the first transfer branch, and each of the cyclic shifters is placed In a corresponding transfer branch. 10. The transmitter of claim 1, further comprising: a guard interval (161, 162) from at least one placed before the at least one processor and configured to add a number of guard intervals to the at least one signal ,...,16ητ). 11. A linear convolver as claimed in claim 10, wherein the at least one processor is configured to linearly convolve a signal provided by the at least one guard interval adder with the respective multipath channel. 134798.doc -2 · 200935792 • A request item alpha transmitter, wherein the at least one processor is a circular convolver configured to cyclically convolve the at least one signal with the respective multipath channel. 13. The transmitter of claim 12, further comprising: - 1 less - placed after the at least one processor and configured to add a number of guard intervals to one; 25, 1, _. To a guard interval adder (361, 362, ..., 36nτ) β ❹ 14_ in the signal provided by a processor, such as the transmitter of claim 1 () or 13, wherein the transmitter includes and each transport knife A plurality of guard interval adders, each guard interval adder is placed in a corresponding transfer branch. 15. The transmitter of claim 1, further comprising: an encoder (10; 30) configured to encode an input data stream; - an interleaver configured to interleave a signal provided by the encoder ( 11 ; 31); - a mapper φ (12; 32) configured to map a signal provided by the interleaver; and - configured to convert - the signal provided by the mapper from a frequency domain to a time domain And providing a converter (13; 33) for the resulting signal to the respective transmit branches of the plurality of transmit branches. A transmission system comprising: at least one transmitter such as a request item; and at least one receiver. 17. The system of claim 16, wherein the continuation of the device is at least a portion of the wireless network. 134798.doc 200935792 18. The system of claim 16, wherein the system is configured to perform a number of multiple input multiple output transfers. 19. A method of transmitting, comprising: 14ητ; 341 carrying a (S1) signal over a plurality of transmission branches 41, 142, ... 342, ..., 34ητ); by means of - separate multipath channels The mode processing (s 2 ) is carried at least one of the plurality of transport branch symbols; and the signal output (S3) on at least one of the transport branches is a signal provided by a corresponding transmit branch. 2〇_ A computer program product for a computer that is included in the production. Execute the right-hand software code section of the production °" when running on this computer. ❹ 134798.doc