Embodiment
Describe the present invention referring to accompanying drawing:
In the MIMO of space multiplexing system transmitter, suppress because between the multiway transmission signal that spatial coherence causes sending via many transmit antennas between antenna during the phase mutual interference, signal to be transmitted is carried out phase rotating process, so that the phase place of the described multiway transmission signal that sends via many transmit antennas is rotated respectively different angles.Particularly, for single codeword space multiplexing system and many code word space multiplex system, signal to be transmitted is carried out the phase rotating processing can occur between the different transmitting terminal signal treatment steps.
Fig. 2 shows according to a specific embodiment of the present invention, utilizes phase rotating to process to suppress because the flow chart of the method for phase mutual interference between the multiway transmission signal that spatial coherence causes sending via many transmit antennas between antenna in the MIMO of single codeword space multiplexing system transmitter.
In this embodiment, execution in step S11 at first, a plurality of modulation signal subsequences of corresponding described multiway transmission signal are rotated respectively different phase angles in will the modulated signal sequences after modulation, also be, the phase place of each modulation signal in each modulation signal subsequence is all rotated a corresponding phase angle, thereby obtain the modulated signal sequences behind phase rotating;
Secondly execution in step S12 goes here and there the modulated signal sequences behind phase rotating and changes, to generate the multidiameter delay signal to be transmitted corresponding with described multiway transmission signal.
It will be appreciated by those skilled in the art that, in this embodiment, although the modulation after, the string and the conversion before signal be the one-channel signal sequence, as long as but know each signal in the one-channel signal sequence after the modulation and corresponding situation through the multichannel signal to be transmitted after string and the conversion, multichannel corresponding with multichannel signal to be transmitted in the one-channel signal sequence before just can determining after modulation, go here and there and changing is modulated the subsignal sequence, thereby can realize the operation to the different phase angle of a plurality of modulation signal subsequences rotations.Particularly, if the modulated signal sequences after the modulation is gone here and there with putting in order of odd even and is converted to the parallel signal to be transmitted of two-way, so, as long as first phase angle of the modulation signal subsequence that the symbol of corresponding odd bits consists of in the modulated signal sequences after will modulating rotation, and second phase angle of modulation signal subsequence rotation that the symbol of corresponding even bit consists of is got final product, and wherein the first phase angle is different from the second phase angle.As mentioned above, modulated signal sequences after the modulation can go here and there and change by any way, but this does not affect flesh and blood of the present invention, as long as know after the modulation the one-channel signal sequence with through the corresponding situation of multichannel signal to be transmitted after string and the conversion, just can be to after the modulation, the different angle of a plurality of subsequence rotations in the one-channel signal sequence before string and the conversion.
Particularly, the above-mentioned out of phase angle that two paths of signals is rotated can calculate according to different modulation systems, for adopting the BPSK modulation system, phase rotating 0 degree of the signal transmission that sends via a transmit antennas wherein, the phase rotating pi/2 of the signal transmission that sends via another transmit antennas wherein; For adopting the QPSK modulation system, phase rotating 0 degree of the signal transmission that sends via a transmit antennas wherein, the phase rotating π of the signal transmission that sends via another transmit antennas wherein/4; For adopting the 16QAM modulation system, phase rotating 0 degree of the signal transmission that sends via a transmit antennas wherein, the phase rotating π of the signal transmission that sends via another transmit antennas wherein/8.
Further, for the space multiplexing system transmitter that many transmit antennas are arranged, the different angles of the phase rotating of the multiway transmission signal that sends via many transmit antennas consist of an arithmetic progression, for adopting the BPSK modulation system, the tolerance of the arithmetic progression that the different angles of the phase rotating of the multiway transmission signal that sends via many transmit antennas consist of is
, wherein, N is the number of transmitting antenna, the phase rotation angle of the N road signal transmission that then sends via the N transmit antennas is respectively 0,
Particularly, if number of transmit antennas N=4, the phase rotation angle of 4 road signal transmissions that then send via 4 transmit antennas is respectively 0, π/6, π/3, pi/2.For adopting the QPSK modulation system, the tolerance of the arithmetic progression that the different angles of the phase rotating of the multiway transmission signal that sends via many transmit antennas consist of is
, wherein, N is the number of transmitting antenna, the phase rotation angle of the N road signal transmission that then sends via the N transmit antennas is respectively 0,
Particularly, if number of transmit antennas N=4, the phase rotation angle of 4 road signal transmissions that then send via 4 transmit antennas is respectively 0, π/12, π/6, π/4.For adopting the 16QAM modulation system, the tolerance of the arithmetic progression that the different angles of the phase rotating of the multiway transmission signal that sends via many transmit antennas consist of is
, wherein, N is the number of transmitting antenna, the phase rotation angle of the N road signal transmission that then sends via the N transmit antennas is respectively 0,
Particularly, if number of transmit antennas N=4, the phase rotation angle of 4 road signal transmissions that then send via 4 transmit antennas is respectively 0, pi/2 4, π/12, π/8.
Certainly, those skilled in the art will be understood that, one group of a plurality of different angles that also can adopt other modes to obtain to multichannel signal to be transmitted in according to the transmitter of space multiplexing system of the present invention are carried out phase rotating and are processed, the corresponding rotatable phase angle of signal to be transmitted of only need not going the same way is mutually different, and is getting final product of knowing in advance of receiver.
Mimo system realizes that jumbo prerequisite is that the signal from each transmitting antenna that the docking of reception function is received carries out good decorrelation processing, and the necessary condition of carrying out this processing is receiving terminal channel is compared accurate estimation, obtain more accurately channel information, thereby can correctly recover disturbed and signal noise pollution.
At receiving terminal, for the ease of channel being compared accurate estimation, usually, at transmitting terminal, signal needs to insert pilot signal before sending via many transmit antennas.At the transmitting terminal pilot signal transmitted dual mode is arranged, first kind of way is to use common pilot signal, and the second way is to use dedicated pilot signal.
When transmitting terminal used public guide frequency, multichannel signal to be transmitted inserted a plurality of common pilot signals before sending via many transmit antennas, generating with the multichannel of pilot frequency information signal to be transmitted, and sent via many transmit antennas respectively; When transmitting terminal uses dedicated pilot signal, before multichannel signal to be transmitted sends via many transmit antennas, at first, carry out respectively the identical phase rotating of phase rotation angle of its corresponding each road signal transmission, to obtain a plurality of pilot signals through phase rotating; Then, described a plurality of pilot signals through phase rotating are inserted in its corresponding multichannel through the phase rotating signal to be transmitted, to obtain to have the signal to be transmitted of the multichannel through phase rotating through the pilot signal of phase rotating.
In this embodiment, before the modulation treatment process, also tackle input signal sequence and carry out various processing, for example, FEC coding and interweave etc.; Equally, transmitter also needs the multi-path parallel signal that obtains after string and the transfer process is carried out the processing such as up-conversion, and this should be known in those skilled in the art, and therefore not to repeat here.
In the single codeword space multiplexing system, above-mentioned phase rotating to multiway transmission signal can also other modes be realized.Fig. 3 shows according to another embodiment of the present invention, utilizes phase rotating to process to suppress because the flow chart of the method for phase mutual interference between the multiway transmission signal that spatial coherence causes sending via many transmit antennas between antenna in the MIMO of single codeword space multiplexing system transmitter.
Particularly, in step S11 ', the burst after the modulation is directly gone here and there and changed, to obtain multidiameter delay signal to be transmitted; Then, the phase place of described multidiameter delay signal to be transmitted is rotated respectively the out of phase angle, to generate the multichannel corresponding with described multiway transmission signal through the signal parallel to be transmitted of phase rotating.
When transmitting terminal used public guide frequency, multichannel signal to be transmitted inserted a plurality of common pilot signals before sending via many transmit antennas, generating with the multichannel of pilot frequency information signal to be transmitted, and sent via many transmit antennas respectively; When transmitting terminal uses dedicated pilot signal, before multichannel signal to be transmitted sends via many transmit antennas, at first, carry out respectively the identical phase rotating of phase rotation angle of its corresponding each road signal transmission, to obtain a plurality of pilot signals through phase rotating; Then, described a plurality of pilot signals through phase rotating are inserted in its corresponding multichannel through the phase rotating signal to be transmitted, to obtain to have the signal to be transmitted of the multichannel through phase rotating through the pilot signal of phase rotating.
Similarly, in this embodiment, before string and translation process, also tackle input signal sequence and carry out various processing, for example, FEC coding, interweave and modulation etc.; Equally, after obtaining multi-path parallel signal after to string and transfer process and carrying out phase rotating, transmitter also needs carry out the processing such as up-conversion to the multichannel signal to be transmitted through phase rotating, and this should be known in those skilled in the art, and therefore not to repeat here.
It will be understood by those skilled in the art that wherein the different angles of the phase rotating of the parallel signal to be transmitted in every road can be calculated gained according to different modulation systems.Concrete account form to Fig. 2 according to a specific embodiment of the present invention, in the MIMO of single codeword space multiplexing system transmitter, utilize phase rotating to process to suppress not repeat them here owing to relate in the detailed description of the flow chart of the method for phase mutual interference between the multiway transmission signal that spatial coherence causes sending via many transmit antennas between antenna.
Fig. 4 shows according to another embodiment of the present invention, utilizes phase rotating to process to suppress because the flow chart of the method for phase mutual interference between the multiway transmission signal that spatial coherence causes sending via many transmit antennas between antenna in the MIMO of many code word space multiplex system transmitter.
Concrete, in step S21, with the phase rotating different angles of the multichannel waiting for transmission modulation signal corresponding with described multiway transmission signal after modulation, to generate the multichannel corresponding with described multiway transmission signal through the signal to be transmitted of phase rotating.
When transmitting terminal used public guide frequency, multichannel signal to be transmitted inserted a plurality of common pilot signals before sending via many transmit antennas, generating with the multichannel of pilot frequency information signal to be transmitted, and sent via many transmit antennas respectively; When transmitting terminal uses dedicated pilot signal, before multichannel signal to be transmitted sends via many transmit antennas, at first, carry out respectively the identical phase rotating of phase rotation angle of its corresponding each road signal transmission, to obtain a plurality of pilot signals through phase rotating; Then, described a plurality of pilot signals through phase rotating are inserted in its corresponding multichannel through the phase rotating signal to be transmitted, to obtain to have the signal to be transmitted of the multichannel through phase rotating through the pilot signal of phase rotating.
In this embodiment, before string and translation process, at first tackle input signal sequence and go here and there and change, to obtain the multi-path parallel signal sequence, also will carry out various processing to each road parallel signal sequences subsequently, for example, FEC coding, interweave and modulation etc.; Equally, after the multichannel modulation signal was carried out phase rotating, transmitter also needed the multichannel signal to be transmitted through phase rotating is carried out the processing such as up-conversion, and this should be known in those skilled in the art, and therefore not to repeat here.
It will be understood by those skilled in the art that wherein, after modulation can calculate gained according to different modulation systems from the different angles of phase rotating multichannel modulation signal waiting for transmission corresponding to described multiway transmission signal.Concrete account form to Fig. 2 according to a specific embodiment of the present invention, in the MIMO of single codeword space multiplexing system transmitter, utilize phase rotating to process to suppress not repeat them here owing to relate in the detailed description of the flow chart of the method for phase mutual interference between the multiway transmission signal that spatial coherence causes sending via many transmit antennas between antenna.
Fig. 5 shows according to a specific embodiment of the present invention, utilizes phase rotating to process to suppress because the structural representation of the transmitter of phase mutual interference between the multiway transmission signal that spatial coherence causes sending via many transmit antennas between antenna in 2 * 2 (two reception antennas of two transmit antennas) single codeword space multiplexing system.Although it will be understood by those skilled in the art that only to show two transmit antennas 16a and 16b among Fig. 5, in concrete the application, can there be many transmit antennas.
Fig. 5 and Fig. 1 distinguish part and are, except FEC encoder 11, interleaver 12, modulator 13, deserializer 15, outside transmitting antenna 16a and the 16b, also comprise phase rotating device 14, it will be understood by those skilled in the art that for string and be converted to the situation of N road parallel signal, also can comprise N phase rotating device, N〉2.
Particularly, 11 pairs of input signals of FEC encoder are encoded, with the burst behind the acquisition coding; Burst behind 12 pairs of codings of interleaver interweaves, the burst after interweaving with acquisition; Burst after 13 pairs of modulators interweave is modulated, with the burst after the acquisition modulation; Burst after 15 pairs of modulation of deserializer carries out serial/parallel conversion, with the two-way parallel signal sequences after acquisition string and the conversion; 14 pairs of phase places via the multiway transmission signal of transmitting antenna 16a and 16b transmission of phase rotating device are rotated respectively, to generate the signal to be transmitted behind phase rotating.
When transmitting terminal uses public guide frequency, multichannel signal to be transmitted need comprise the pilots insertion device before sending via many transmit antennas, is used for inserting a plurality of common pilot signals, generating with the multichannel of pilot frequency information signal to be transmitted, and send via many transmit antennas respectively; When transmitting terminal uses dedicated pilot signal, before multichannel signal to be transmitted sends via many transmit antennas, need comprise the pilot phase whirligig, be used for a plurality of pilot signals are carried out respectively the identical phase rotating of phase rotation angle of its corresponding each road signal transmission, to obtain a plurality of pilot signals through phase rotating; Also need comprise the pilots insertion device, be used for described a plurality of pilot signals through phase rotating are inserted its corresponding multichannel through phase rotating signal to be transmitted, to obtain to have the signal to be transmitted of the multichannel through phase rotating through the pilot signal of phase rotating.
It will be understood by those skilled in the art that transmitter also need be treated signal transmission and carry out the processing such as up-conversion after string and processing procedure, this should be known in those skilled in the art, and is not shown among Fig. 5 for simplicity's sake, does not also give unnecessary details at this.
It will be appreciated by those skilled in the art that, in this embodiment, although the modulation after, the string and the conversion before signal be the one-channel signal sequence, as long as but know each signal in the one-channel signal sequence after the modulation and corresponding situation through the multichannel signal to be transmitted after string and the conversion, multichannel corresponding with multichannel signal to be transmitted in the one-channel signal sequence before just can determining after modulation, go here and there and changing is modulated the subsignal sequence, thereby can realize the operation to the different phase angle of a plurality of modulation signal subsequences rotations.Particularly, if the modulated signal sequences after the modulation is gone here and there with putting in order of odd even and is converted to the parallel signal to be transmitted of two-way, so, as long as first phase angle of the modulation signal subsequence that the symbol of corresponding odd bits consists of in the modulated signal sequences after will modulating rotation, and second phase angle of modulation signal subsequence rotation that the symbol of corresponding even bit consists of is got final product, and wherein the first phase angle is different from the second phase angle.As mentioned above, modulated signal sequences after the modulation can go here and there and change by any way, but this does not affect flesh and blood of the present invention, as long as know after the modulation the one-channel signal sequence with through the corresponding situation of multichannel signal to be transmitted after string and the conversion, just can be to after the modulation, the different angle of a plurality of subsequence rotations in the one-channel signal sequence before string and the conversion.
Particularly, the above-mentioned out of phase angle that two paths of signals is rotated can calculate according to different modulation systems, for adopting the BPSK modulation system, phase rotating 0 degree of the signal transmission that sends via the first transmitting antenna 16a, the phase rotating pi/2 of the signal transmission that sends via the second transmitting antenna 16b; For adopting the QPSK modulation system, phase rotating 0 degree of the signal transmission that sends via the first transmitting antenna 16a, the phase rotating π of the signal transmission that sends via the second transmitting antenna 16b/4; For adopting the 16QAM modulation system, phase rotating 0 degree of the signal transmission that sends via the first transmitting antenna 16a, the phase rotating π of the signal transmission that sends via the second transmitting antenna 16b/8.
Further, for the space multiplexing system MIMO transmitter that many transmit antennas are arranged, the different angles of the phase rotating of the multiway transmission signal that sends via many transmit antennas consist of an arithmetic progression, for adopting the BPSK modulation system, the tolerance of the arithmetic progression that the different angles of the phase rotating of the multiway transmission signal that sends via many transmit antennas consist of is
, wherein, N is the number of transmitting antenna, the phase rotation angle of the N road signal transmission that then sends via the N transmit antennas is respectively 0,
。Particularly, if number of transmit antennas N=4, the phase rotation angle of 4 road signal transmissions that then send via 4 transmit antennas is respectively 0, π/6, π/3, pi/2.For adopting the QPSK modulation system, the tolerance of the arithmetic progression that the different angles of the phase rotating of the multiway transmission signal that sends via many transmit antennas consist of is
, wherein, N is the number of transmitting antenna, the phase rotation angle of the N road signal transmission that then sends via the N transmit antennas is respectively 0,
Particularly, if number of transmit antennas N=4, the phase rotation angle of 4 road signal transmissions that then send via 4 transmit antennas is respectively 0, π/12, π/6, π/4.For adopting the 16QAM modulation system, the tolerance of the arithmetic progression that the different angles of the phase rotating of the multiway transmission signal that sends via many transmit antennas consist of is
, wherein, N is the number of transmitting antenna, the phase rotation angle of the N road signal transmission that then sends via the N transmit antennas is respectively 0,
Particularly, if number of transmit antennas N=4, the phase rotation angle of 4 road signal transmissions that then send via 4 transmit antennas is respectively 0, pi/2 4, π/12, π/8.
Certainly, those skilled in the art will be understood that, one group of a plurality of different angles that also can adopt other modes to obtain to multichannel signal to be transmitted in according to the transmitter of space multiplexing system of the present invention are carried out phase rotating and are processed, the corresponding rotatable phase angle of signal to be transmitted of only need not going the same way is mutually different, and is getting final product of knowing in advance of receiver.
Further, for the single codeword space multiplexing system, with signal to be transmitted carry out phase rotating process can modulate after, before the serial to parallel conversion, also can occur after the serial to parallel conversion.
Fig. 6 shows according to another embodiment of the present invention, utilizes phase rotating to process to suppress because the structural representation of the transmitter of phase mutual interference between the multiway transmission signal that spatial coherence causes sending via many transmit antennas between antenna in 2 * 2 (two reception antennas of two transmit antennas) single codeword space multiplexing system.Although it will be understood by those skilled in the art that only to show two transmit antennas 16a ' and 16b ' among Fig. 6, in concrete the application, can there be many transmit antennas.
The difference of Fig. 6 and Fig. 5 is, treats the processing that signal transmission carries out phase rotating among Fig. 6 and occurs in after the serial to parallel conversion.Particularly, in Fig. 6, FEC encoder 11 ' is encoded to input signal, to obtain the burst behind the coding; Interleaver 12 ' interweaves to the burst after encoding, the burst after interweaving with acquisition; Modulator 13 ' is modulated the burst after interweaving, with the burst after the acquisition modulation; Deserializer 15 ' carries out serial/parallel conversion to the burst after modulating, with the two-way parallel signal sequences after acquisition string and the conversion; The first phase place whirligig 14a ' is rotated the phase place of the signal transmission that sends via the first transmitting antenna 16a ', to generate the signal to be transmitted behind phase rotating, the second phase place whirligig 14b ' is rotated the phase place of the signal transmission that sends via the second transmitting antenna 16b ', to generate the signal to be transmitted behind phase rotating, it will be understood by those skilled in the art that, for string and be converted to the situation of N road parallel signal, also can comprise N phase rotating device, N〉2.
When transmitting terminal uses public guide frequency, multichannel signal to be transmitted need comprise the pilots insertion device before sending via many transmit antennas, is used for inserting a plurality of common pilot signals, generating with the multichannel of pilot frequency information signal to be transmitted, and send via many transmit antennas respectively; When transmitting terminal uses dedicated pilot signal, before multichannel signal to be transmitted sends via many transmit antennas, need comprise the pilot phase whirligig, be used for a plurality of pilot signals are carried out respectively the identical phase rotating of phase rotation angle of its corresponding each road signal transmission, to obtain a plurality of pilot signals through phase rotating; Also need comprise the pilots insertion device, be used for described a plurality of pilot signals through phase rotating are inserted its corresponding multichannel through phase rotating signal to be transmitted, to obtain to have the signal to be transmitted of the multichannel through phase rotating through the pilot signal of phase rotating.
It will be understood by those skilled in the art that also to comprise other devices that carry out the processing such as up-conversion be used to treating signal transmission in the transmitter, this should be known in those skilled in the art, and therefore not to repeat here.
Particularly, the above-mentioned out of phase angle that two paths of signals is rotated can calculate according to different modulation systems, for adopting the BPSK modulation system, phase rotating 0 degree of the signal transmission that sends via the first transmitting antenna 16a ', the phase rotating pi/2 of the signal transmission that sends via the second transmitting antenna 16b '; For adopting the QPSK modulation system, phase rotating 0 degree of the signal transmission that sends via the first transmitting antenna 16a ', the phase rotating π of the signal transmission that sends via the second transmitting antenna 16b '/4; For adopting the 16QAM modulation system, phase rotating 0 degree of the signal transmission that sends via the first transmitting antenna 16a ', the phase rotating π of the signal transmission that sends via the second transmitting antenna 16b '/8.
Fig. 7 shows according to another embodiment of the present invention, utilizes phase rotating to process to suppress because the structural representation of the transmitter of phase mutual interference between the multiway transmission signal that spatial coherence causes sending via many transmit antennas between antenna in 2 * 2 (two reception antennas of two transmit antennas) many code word space multiplex system.Although it will be understood by those skilled in the art that only to show two transmit antennas 26a and 26b among Fig. 7, in concrete the application, can there be many transmit antennas.
It will be appreciated by those skilled in the art that, in the transmitter of single codeword space multiplexing system, only need carry out modulating-coding to one road signal, finish that all encodes, interweave, will go here and there and change through the burst of above-mentioned processing procedure acquisition again behind the modulated process; And in the transmitter of many code word space multiplex system, at first input signal sequence is gone here and there and changes, generate the multi-path parallel signal sequence, then, need to the multi-path parallel signal sequence carry out respectively separately coding, interweave, modulation treatment.
Particularly, in Fig. 7,21 pairs of input signals of deserializer are gone here and there and are changed, with the two-way parallel signal sequences after acquisition string and the conversion;
FEC encoder 22 and 22 ' carries out respectively the FEC encoder to the two-way parallel signal sequences after string and the conversion respectively, with the two-way parallel signal sequences behind the acquisition coding;
Interleaver 23 and 23 ' interweaves respectively to the two paths of signals sequence behind the FEC coding, the two-way parallel signal sequences after interweaving with acquisition;
Modulator 24 and 24 ' is modulated respectively the two paths of signals sequence after interweaving, with the two-way parallel signal sequences after the acquisition modulation;
Wherein, the first phase place whirligig 25a carries out the phase angle rotation to road parallel signal sequences in the two-way parallel signal sequences after modulating, generating one tunnel signal to be transmitted behind phase rotating, with through such as subsequent treatment such as up-conversions by being sent by the first transmitting antenna 26a;
And the second phase place whirligig 25b carries out phase rotating to another road parallel signal sequences in the two-way parallel signal sequences after modulating, to generate the to be transmitted signal of another road behind phase rotating, to pass through such as subsequent treatment such as up-conversions by being sent by the second transmitting antenna 26b.
It will be understood by those skilled in the art that for string and be converted to the situation of N road parallel signal, also can comprise N phase rotating device, N 2.
When transmitting terminal uses public guide frequency, multichannel signal to be transmitted need comprise the pilots insertion device before sending via many transmit antennas, is used for inserting a plurality of common pilot signals, generating with the multichannel of pilot frequency information signal to be transmitted, and send via many transmit antennas respectively; When transmitting terminal uses dedicated pilot signal, before multichannel signal to be transmitted sends via many transmit antennas, need comprise the pilot phase whirligig, be used for a plurality of pilot signals are carried out respectively the identical phase rotating of phase rotation angle of its corresponding each road signal transmission, to obtain a plurality of pilot signals through phase rotating; Also need comprise the pilots insertion device, be used for described a plurality of pilot signals through phase rotating are inserted its corresponding multichannel through phase rotating signal to be transmitted, to obtain to have the signal to be transmitted of the multichannel through phase rotating through the pilot signal of phase rotating.
As mentioned above, for every road parallel signal, after modulator and phase rotating device, transmitter also comprises the device that carries out the processing such as up-conversion be used to treating signal transmission, and this should be known in those skilled in the art, for simplicity's sake, not shown in Fig. 7, do not give unnecessary details at this yet.
Particularly, the above-mentioned out of phase angle that two paths of signals is rotated can calculate according to different modulation systems, for adopting the BPSK modulation system, phase rotating 0 degree of the signal transmission that sends via the first transmitting antenna 26a, the phase rotating pi/2 of the signal transmission that sends via the second transmitting antenna 26b; For adopting the QPSK modulation system, phase rotating 0 degree of the signal transmission that sends via the first transmitting antenna 26a, the phase rotating π of the signal transmission that sends via the second transmitting antenna 26b/4; For adopting the 16QAM modulation system, phase rotating 0 degree of the signal transmission that sends via the first transmitting antenna 26a, the phase rotating π of the signal transmission that sends via the second transmitting antenna 26b/8.
Certainly, those skilled in the art will be understood that, one group of a plurality of different angles that also can adopt other modes to obtain to multichannel signal to be transmitted in according to the transmitter of space multiplexing system of the present invention are carried out phase rotating and are processed, the corresponding rotatable phase angle of signal to be transmitted of only need not going the same way is mutually different, and is getting final product of knowing in advance of receiver.
In the MIMO of space multiplexing system receiver, during the signal transmission of the multichannel that sends via many transmit antennas in being received in transmitter of the present invention behind phase rotating, the contrary rotation of phase place of carrying out processing with the phase rotating of transmitter terminal contrary from the signal transmission of multichannel behind phase rotating of many transmit antennas in the reception signal that every reception antenna is received is processed.Concrete step is shown in the described flow chart of Fig. 8.
Fig. 8 shows according to a specific embodiment of the present invention, is used for being received in the flow chart of the method for the signal transmission of multichannel behind phase rotating that transmitter sends via many transmit antennas in the MIMO of space multiplexing system receiver.
In this embodiment, execution in step S31 at first, obtain every road signal transmission of sending from every transmit antennas in the described reception signal via the transmission coefficient of transmission channel;
Secondly, execution in step S32, with described every road signal transmission institute via transmission channel the transmission coefficient phase place respectively with transmitter terminal different rotation angle in the same manner, with the transmission coefficient of generation behind phase rotating;
At last, execution in step S33 detects described reception signal according to described transmission coefficient behind phase rotating, with the signal transmission that obtains respectively to be sent by every transmit antennas.
In this embodiment, the different angles that the different angles that the phase place of the transmission coefficient that relates among the step S32 is rotated are rotated corresponding to the phase place of the multiway transmission signal that sends via many transmit antennas in the transmitter, particularly, the phase place of the above-mentioned transmission coefficient different angles of rotating can be calculated gained according to different modulation systems.Concrete account form to Fig. 2 according to a specific embodiment of the present invention, in the MIMO of single codeword space multiplexing system transmitter, utilize phase rotating to process to suppress not repeat them here owing to relate in the detailed description of the flow chart of the method for phase mutual interference between the multiway transmission signal that spatial coherence causes sending via many transmit antennas between antenna.
Can understand better the described flow process of Fig. 8 in conjunction with Fig. 9, channel estimating among Fig. 9 is based on common pilot symbols, particularly, when wherein reception antenna of receiving terminal receives the two-way that sends via two transmit antennas behind the signal transmission behind the phase rotating, wherein, the phase rotating of one road signal transmission first phase angle, the phase rotating of another road signal transmission second phase angle, at first, from the signal that receives, extract pilot frequency information, then, estimate by pilot frequency information the two-way signal transmission that sends from two transmit antennas via the transmission coefficient of transmission channel, correspondingly, the step S31 described in this step corresponding diagram 8; Subsequently, with the phase place of the transmission coefficient that estimates respectively with transmitter terminal different rotation angle in the same manner, correspondingly, the step S32 described in this step corresponding diagram 8, wherein, the transmission coefficient h
1Phase rotating first phase angle, the transmission coefficient h
2Phase rotating second phase angle, to generate the transmission coefficient behind phase rotating; At last, will and extract the signal behind the pilot frequency information and together send into detector through the transmission coefficient behind the phase rotating, with the signal transmission that obtains respectively to be sent by every transmit antennas, correspondingly, the step S33 described in this step corresponding diagram 8.
Fig. 9 shows according to a specific embodiment of the present invention, in 2 * 2 (two reception antennas of two transmit antennas) space multiplexing system, be used for being received in multichannel that transmitter sends via many transmit antennas behind phase rotating signal transmission and carry out the structural representation of the receiver of channel estimating based on common pilot symbols.Space multiplexing system MIMO receiver 3 shown in Figure 9 comprises pilot extractor 31, channel estimator 32, the first phase place whirligig 33, the second phase place whirligigs 33 ', detector 34, deinterleaver 35 and fec decoder devices 36.
Concrete, when wherein reception antenna of receiving terminal receives the two-way that sends via two transmit antennas behind the signal transmission behind the phase rotating, wherein, the phase rotating of one road signal transmission first phase angle, the phase rotating of another road signal transmission second phase angle.
At first, pilot extractor 31 is extracted pilot frequency information from the signal that receives;
Then, channel estimator 32 estimate by pilot frequency information the two-way signal transmission that sends from two transmit antennas via the transmission coefficient of transmission channel;
Then, the first phase place whirligig 33 and the second phase place whirligig 33 ' carry out phase rotating with transmitter terminal respectively accordingly with the transmission coefficient that estimates, wherein, identical with the phase rotation angle of in phase rotation angle corresponding to the transmission coefficient of every road signal transmission and the transmitter every road signal transmission being done, at this, the first transmission coefficient h corresponding with first via signal transmission
1Phase rotating first phase angle, the second channel transmission coefficient h corresponding with the second road signal transmission
2Phase rotating second phase angle, to generate two transmission coefficients behind phase rotating;
Subsequently, detector 34 utilizes and detects having extracted the signal behind the pilot frequency information through two transmission coefficients behind the phase rotating, with the two-way signal transmission that obtains respectively to be sent by every transmit antennas; Then, deinterleaver 35 and the fec decoder device 36 two-way signal transmission that sends via two transmit antennas that will obtain deinterleaves respectively and decodes; At last, decoded signal is carried out the bit sequence that hard decision obtains receiving.
Particularly, divide from the type of channel estimation method input data, the mimo channel estimation scheme can be divided into time domain and frequency domain two large class methods.Frequency domain method is mainly for multicarrier system; Time domain approach is applicable to all single carriers and multi-carrier MIMO system, and it estimates the attenuation coefficient of each multipath component in the fading channel by means of the statistical property of training sequence or transmission data.Be based on the situation that common pilot symbols is carried out channel estimating shown in Fig. 9, because channel estimating is based on common pilot symbols, all users' receiver can use this common pilot symbols to carry out channel estimating, in this case, the estimated channel of each receiver user is physical channel, therefore, in a plurality of transmission coefficients corresponding to the multiway transmission signal that will estimate (two transmission coefficient h shown in Fig. 9 for example
1And h
2) and extracted the signal behind the pilot frequency information and together sent into detector before, must be with the transmission coefficient h
1And h
2Phase place rotated respectively first phase angle and second phase angle.
In a preferred embodiment, also can carry out channel estimating based on dedicated pilot symbol, this dedicated pilot symbol only makes separately to estimate its transmission coefficient by each targeted customer, also be, at transmitter terminal, before sending, carried out the phase rotating processing of the phase angle identical with corresponding one road signal transmission via the pilot signal that every transmit antennas sends, comprised phase rotation angle in the acquisition channel transmission system corresponding with every road signal transmission when then channel estimator 32 carries out channel estimating in the receiver 3, therefore need not channel is estimated the transmission coefficient h that obtains
1And h
2Phase place do any rotation and process, and can be with this transmission coefficient h
1And h
2Directly send in the detector with having extracted the signal behind the pilot frequency information, carry out Check processing.
Those skilled in the art are appreciated that in conjunction with figure, in the present embodiment, Figure 10 shows according to an embodiment of the invention, adopts the simulation performance figure of 2 * 2 (two reception antennas of two transmit antennas) spatial reuse (SM) system of QPSK modulation system in irrelevant with the relevant smooth Rayleigh fast fading channel in space; And Figure 11 shows according to an embodiment of the inventionly, adopts the simulation performance figure of 2 * 2 (two reception antennas of two transmit antennas) spatial reuse (SM) system of 16QAM modulation system in irrelevant with the relevant smooth Rayleigh fast fading channel in space.Although it will be appreciated by those skilled in the art that and only adopted two transmit antennas and two reception antennas in the related space multiplexing system of Figure 10 and Figure 11, in concrete the application, can there be many transmit antennas and Duo Gen reception antenna.Particularly, to adopt message length be that 400 code check is 1/2 (11,13) to the FED of the transmitter terminal of related 2 * 2 (two reception antennas of two transmit antennas) spatial reuse (SM) system of Figure 10 and Figure 11 coding
8The turbo coding it will be understood by those skilled in the art that described FED coding can adopt other coded systems except the turbo coding, and this does not affect flesh and blood of the present invention, and no further details to be given herein.The modulation system of the transmitter terminal of 2 * 2 (two reception antennas of two transmit antennas) spatial reuse (SM) system that Figure 10 is related adopts the QPSK modulation system, it will be appreciated by those skilled in the art that, described modulation system can adopt other modulation systems except the QPSK modulation, this does not affect flesh and blood of the present invention, and no further details to be given herein.
The modulation system of the transmitter terminal of 2 * 2 (two reception antennas of two transmit antennas) spatial reuse (SM) system that Figure 11 is related adopts the 16QAM modulation system, it will be appreciated by those skilled in the art that, described modulation system can adopt other modulation systems except the 16QAM modulation, this does not affect flesh and blood of the present invention, and no further details to be given herein.More specifically, the related smooth Rayleigh fast fading channel of Figure 10 and Figure 11 comprises the uncorrelated channel in space, and the space microfacies is closed channel (antenna distance between two transmit antennas of transmitting terminal is 4 wavelength) and serious spatial correlation channel (antenna distance between two transmit antennas of transmitting terminal is 0.5 wavelength).It will be appreciated by those skilled in the art that, when the antenna distance between two transmit antennas of transmitting terminal is 4 wavelength, transmission channel can be considered the space microfacies and closes channel, when the antenna distance between two transmit antennas of transmitting terminal was 0.5 wavelength, transmission channel can be considered the serious correlated channels in space.Among Figure 10 and Figure 11, with blockage
![Figure S07142623520070724D000201](https://patentimages.storage.googleapis.com/5c/8c/79/34f490984d6858/S07142623520070724D000201.png)
The curve of mark is corresponding to be the performance curve that multiway transmission signal that sends via many transmit antennas is not carried out spatial reuse (SM) system of phase rotating processing in transmitter, and corresponding with the curve of fork " * " mark is the performance curve that the multiway transmission signal that sends via many transmit antennas has been carried out spatial reuse (SM) system of phase rotating processing in transmitter.Particularly, Far Left overlap fully two is respectively with blockage
The curve of mark and take the fork " * " mark the Curves spatial channel corresponding as the space uncorrelated channel; Its right side almost overlap two is respectively with blockage
The curve of mark and close channel (antenna distance between two transmit antennas of transmitting terminal is as 4 wavelength) take the Curves spatial channel corresponding of fork " * " mark as the space microfacies, rightmost two respectively with blockage
The curve of mark and take the fork " * " mark the Curves spatial channel corresponding as serious spatial correlation channel (antenna distance between two transmit antennas of transmitting terminal is as 0.5 wavelength).More specifically, the abscissa among Figure 10 and Figure 11 represents signal to noise ratio (SNR), and ordinate represents the error rate (BER).
Further, for the uncorrelated channel in space, such phase rotating can not affect the performance of system.Shown in Figure 10 and Figure 11, with blockage
The curve of mark is corresponding to be the performance curve that multiway transmission signal that sends via many transmit antennas is not carried out spatial reuse (SM) system of phase rotating processing in transmitter, corresponding with the curve of fork " * " mark is the performance curve that the multiway transmission signal that sends via many transmit antennas has been carried out spatial reuse (SM) system of phase rotating processing in transmitter, in Figure 10 and Figure 11, two curves overlap fully, and this explanation is carried out the phase rotating processing to the multiway transmission signal that sends via many transmit antennas in transmitter can not affect the performance of system in the uncorrelated channel in space.
Close channel (antenna distance between two transmit antennas of transmitting terminal is 4 wavelength) for the space microfacies, because the attenuation coefficient similitude on many transmit antennas is very little, process little to the performance impact of space multiplexing system so in transmitter, whether the multiway transmission signal that sends via many transmit antennas is carried out phase rotating.Shown in Figure 10 and Figure 11, when the antenna distance between two transmit antennas is 4 wavelength, with blockage
![Figure S07142623520070724D000215](https://patentimages.storage.googleapis.com/8d/a7/77/81f75ca3fd5a78/S07142623520070724D000215.png)
The curve of mark is corresponding to be the performance curve that multiway transmission signal that sends via many transmit antennas is not carried out spatial reuse (SM) system of phase rotating processing in transmitter, corresponding with the curve of fork " * " mark is the performance curve that the multiway transmission signal that sends via many transmit antennas has been carried out spatial reuse (SM) system of phase rotating processing in transmitter, as seen, for in transmitter the multiway transmission signal that sends via many transmit antennas having been carried out the space multiplexing system that phase rotating is processed, its performance slightly is better than the multiway transmission signal that sends via many transmit antennas not being carried out the space multiplexing system that phase rotating is processed in transmitter.
For the serious correlated channels in space (antenna distance between two transmit antennas of transmitting terminal is 0.5 wavelength), owing to the phase place of the multiway transmission signal that sends via many transmit antennas has been rotated respectively different angles, therefore, even have at many transmit antennas in the situation of similar attenuation coefficient, also can not cancel out each other at receiving terminal via the multiway transmission signal that many transmit antennas send, this has greatly improved the performance of spatial reuse.Shown in Figure 10 and Figure 11, when the antenna distance between two transmit antennas is 0.5 wavelength, with blockage
![Figure S07142623520070724D000221](https://patentimages.storage.googleapis.com/73/8c/4e/0728cde95ada1d/S07142623520070724D000221.png)
The curve of mark is corresponding to be the performance curve that multiway transmission signal that sends via many transmit antennas is not carried out spatial reuse (SM) system of phase rotating processing in transmitter, corresponding with the curve of fork " * " mark is the performance curve that the multiway transmission signal that sends via many transmit antennas has been carried out spatial reuse (SM) system of phase rotating processing in transmitter, obviously, for in transmitter the multiway transmission signal that sends via many transmit antennas having been carried out the space multiplexing system that phase rotating is processed, its performance is much better than in transmitter does not carry out the space multiplexing system that phase rotating is processed to the multiway transmission signal that sends via many transmit antennas.
More than specific embodiments of the invention are described, it will be appreciated that the present invention is not limited to above-mentioned specific execution mode, those skilled in the art can make various typings and modification within the scope of the appended claims.