CN105743608B - Method and device for analyzing space frequency block code - Google Patents
Method and device for analyzing space frequency block code Download PDFInfo
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- CN105743608B CN105743608B CN201410764648.6A CN201410764648A CN105743608B CN 105743608 B CN105743608 B CN 105743608B CN 201410764648 A CN201410764648 A CN 201410764648A CN 105743608 B CN105743608 B CN 105743608B
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Abstract
The invention discloses a method for analyzing space frequency block codes, which comprises the steps of respectively determining the background noise of each receiving antenna, wherein the number of the receiving antennas is at least two; transforming the frequency domain receiving signals of the receiving antennas according to the bottom noise of each receiving antenna; and carrying out space frequency block code decoding according to the transformed frequency domain receiving signals of each receiving antenna. The invention also discloses a device for analyzing the space frequency block code. The invention optimizes the method for analyzing the space frequency block code and improves the performance of the wireless communication system.
Description
Technical Field
The present invention relates to the field of communications, and in particular, to a method and an apparatus for resolving a space frequency block code.
Background
In a wireless mobile communication system, signals are subject to various interferences during transmission after being transmitted, thereby causing signal attenuation, and the diversity reception technology is one of the commonly adopted technical measures for effectively resisting fading and improving link reliability. The basic principle of diversity reception is to receive multiple copies carrying the same information through multiple channels (time, frequency or space), and because the transmission characteristics of the multiple channels are different, the fading of the multiple copies of the signal will not be the same, so a certain signal combining technique can be used to make the information contained in the multiple copies more correct to recover the original transmitted signal. Diversity reception is to combat the adverse effects of fading by improving the received signal, but such improvement requires increased receiver complexity.
In the LTE (Long Term Evolution, Long Term Evolution system) standard, SFBC (Space frequency block Code) is adopted as a transmit diversity scheme for two antenna ports, and the basic idea is as follows: after constellation mapping, information bits to be transmitted enter a space-frequency encoder by taking two symbols as a unit. For example, for a two transmit antenna SFBC system, assuming symbol streams input to the SFBC encoder are C1, C2, …, C1 and C2 are transmitted on the 1 st subcarrier of antenna 1 and antenna 2, respectively, and-C2 and-C1 are transmitted on the 2 nd subcarrier of antenna 1 and antenna 2, respectively. Wherein (), the complex number is conjugated, and in LTE, OFDM (Orthogonal Frequency Division Multiplexing) technology is used for signal transmission. For a receiving diversity scheme using SFBC as two antenna ports, the common SFBC analysis method does not consider the situation of different bottom noises of receiving antennas, and the different bottom noises of different receiving antennas also have a certain influence on the SFBC analysis, so that the quality of the restored transmission signal is not optimal under the situation.
Disclosure of Invention
The present invention provides a method and an apparatus for resolving space frequency block codes, which are capable of recovering a transmission signal with higher quality, reducing signal attenuation, and improving performance of a wireless communication system.
To achieve the above object, the present invention provides a method for analyzing space frequency block codes, comprising:
respectively determining the background noise of each receiving antenna, wherein the number of the receiving antennas is at least two;
transforming the frequency domain receiving signals of the receiving antennas according to the bottom noise of each receiving antenna;
and carrying out space frequency block code decoding according to the transformed frequency domain receiving signals of each receiving antenna.
Preferably, the separately determining the noise floor of each receiving antenna comprises:
grouping the channel estimation values of each orthogonal frequency division multiplexing pilot frequency symbol on the frequency domain signal bandwidth of each receiving antenna, wherein the channel estimation values in each group of channel estimation value groups are the channel estimation values corresponding to the adjacent pilot frequency symbols;
and calculating the bottom noise of each receiving antenna according to each group of channel estimation values corresponding to each receiving antenna.
Preferably, the calculating the noise floor of each receiving antenna according to the respective sets of channel estimation values corresponding to each receiving antenna includes:
calculating conjugate multiplication values corresponding to each group of channel estimation values according to each group of channel estimation values of the receiving antenna;
calculating the absolute value of the average value of all the conjugate multiplication values according to each conjugate multiplication value;
calculating the power value of each pilot frequency symbol according to the channel estimation value of each orthogonal frequency division multiplexing pilot frequency symbol on the signal bandwidth of each receiving antenna;
calculating the average value of the power values of all the pilot symbols according to the power value of each pilot symbol;
calculating the absolute value of the difference between the absolute value of the average value of all the conjugate multiplication values and the average value of the power values of all the pilot symbols, wherein the absolute value of the difference is the noise power value of the receiving antenna;
and calculating the arithmetic square root of the noise power value of the receiving antenna according to the noise power value of the receiving antenna, wherein the arithmetic square root is the bottom noise of the receiving antenna.
Preferably, the transforming the frequency domain receiving signals of the receiving antennas according to the noise floor of each receiving antenna includes:
and dividing the frequency domain receiving signal of each receiving antenna by the bottom noise of the receiving antenna to obtain the frequency domain receiving signal transformed by each antenna.
Preferably, the performing space-frequency block code decoding according to the transformed frequency-domain received signal of each receiving antenna includes:
and performing space frequency block code decoding according to the transformed frequency domain receiving signals of each receiving antenna, and determining a sending signal estimation value of a transmitting antenna corresponding to each receiving antenna.
In addition, to achieve the above object, the present invention further provides an apparatus for analyzing a space frequency block code, including:
a bottom noise determining module, configured to determine the bottom noise of each receiving antenna, where the number of the receiving antennas is at least two;
the frequency domain signal transformation module is used for transforming the frequency domain receiving signals of the receiving antennas according to the bottom noise of each receiving antenna;
and the space frequency block code decoding module is used for decoding the space frequency block code according to the transformed frequency domain receiving signals of each receiving antenna.
Preferably, the noise floor determination module includes:
a grouping submodule, configured to group channel estimation values of each orthogonal frequency division multiplexing pilot symbol in the frequency domain signal bandwidth of each receiving antenna, where a channel estimation value in each channel estimation value group is a channel estimation value corresponding to an adjacent pilot symbol;
and the bottom noise calculation submodule is used for calculating the bottom noise of each receiving antenna according to each group of channel estimation values corresponding to each receiving antenna.
Preferably, the noise floor calculation sub-module includes:
a conjugate multiplication value calculating unit, configured to calculate, according to each group of channel estimation values of the receiving antenna, a conjugate multiplication value corresponding to each group of channel estimation values;
a first calculating unit for calculating an absolute value of an average value of all the conjugate multiplication values according to each of the conjugate multiplication values;
a pilot symbol power value calculation unit, configured to calculate a power value of each pilot symbol according to a channel estimation value of each ofdm pilot symbol on a signal bandwidth of each receiving antenna;
a second calculating unit, configured to calculate an average value of the power values of all pilot symbols according to the power value of each pilot symbol;
a receiving antenna noise power value calculating unit, configured to calculate an absolute value of a difference between an absolute value of an average value of all the conjugate multiplication values and an average value of power values of all the pilot symbols, where the absolute value of the difference is a noise power value of a receiving antenna;
and the receiving antenna bottom noise calculating unit is used for calculating the arithmetic square root of the noise power value of the receiving antenna according to the noise power value of the receiving antenna, and the arithmetic square root is the bottom noise of the receiving antenna.
Preferably, the frequency domain signal transformation module is further configured to:
and dividing the frequency domain receiving signal of each receiving antenna by the bottom noise of the receiving antenna to obtain the frequency domain receiving signal transformed by each antenna.
Preferably, the space-frequency block code decoding module is further configured to:
and performing space frequency block code decoding according to the transformed frequency domain receiving signals of each receiving antenna, and determining a sending signal estimation value of a transmitting antenna corresponding to each receiving antenna.
The invention determines the bottom noise of the receiving antenna, transforms the frequency domain receiving signal of the receiving antenna according to the bottom noise of the receiving antenna, and finally carries out SFBC decoding according to the transformed frequency domain receiving signal. The invention considers the influence of different bottom noises of different receiving antennas on the received signal, and normalizes the bottom noise values of different receiving antennas, thereby further optimizing the method for analyzing SFBC.
Drawings
Fig. 1 is a diagram of a transmitting end of a communication system with two transmitting antennas in an LTE system according to a preferred embodiment of the present invention;
fig. 2 shows a receiving end of a communication system with two receiving antennas in an LTE system according to a preferred embodiment of the present invention;
FIG. 3 is a flowchart illustrating a method for analyzing space frequency block codes according to a first embodiment of the present invention;
FIG. 4 is a flowchart illustrating a second embodiment of a method for resolving space frequency block codes according to the present invention;
FIG. 5 is a flowchart illustrating a method for analyzing space frequency block codes according to a third embodiment of the present invention;
FIG. 6 is a diagram illustrating a pilot symbol grouping scheme according to the present invention;
FIG. 7 is a functional block diagram of an apparatus for analyzing space frequency block codes according to a first embodiment of the present invention;
FIG. 8 is a functional block diagram of an apparatus for analyzing space frequency block codes according to a second embodiment of the present invention;
FIG. 9 is a functional block diagram of an apparatus for analyzing space frequency block codes according to a third embodiment of the present invention;
fig. 10 is a diagram showing comparison between the performance of the conventional SFBC analysis method (Original) and the performance of the SFBC analysis method (New) according to the present invention.
The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.
Detailed Description
It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The core idea of the invention is to transform the frequency domain signals of the corresponding receiving antennas by using different bottom noises of different receiving antennas, thereby realizing normalization processing of the different bottom noises of the different receiving antennas, and then performing SFBC decoding according to the transformed frequency domain signals, thereby realizing the purpose of further optimizing and analyzing the SFBC method by the receiving antennas under the influence of different bottom noise factors, and improving the performance of the wireless communication system. The core idea of the invention is applicable to any form of SFBC decoding method with multiple transmitting (multiple transmitting antennas) and multiple receiving (multiple receiving antennas). In the embodiment of the present invention, an SFBC decoding method with two transmitters and two receivers is specifically illustrated.
The specific structure and method steps of the invention will be described in detail below with reference to the accompanying drawings
Referring to fig. 1, fig. 1 is a diagram of a transmitting end of a communication system with two transmitting antennas in an LTE system according to a preferred embodiment of the present invention. The transmitting end includes a channel encoder 11, a modulator 12, an SFBC encoder 13, a transmitting antenna 14, and a transmitting antenna 15. Wherein a channel encoder 11 channel-encodes a signal from a source and inputs the channel-encoded signal to a modulator 12 for digital modulation. The modulated signal is then input to the SFBC encoder 13 to perform SFBC encoding of the modulated signal. Finally, the encoded signal is transmitted to the receiving end through the transmitting antenna 14 and the transmitting antenna 15. In the antenna transmitting diversity scheme at two ends of an LTE system, channel estimation values of pilot symbols are divided into two groups for SFBC coding, and the same SFBC coding block occupies two adjacent subcarriers of two transmitting antennas. For example, assuming that the symbol streams input to the SFBC encoder 13 are C1, C2, …, C1 and C2 are transmitted on the 1 st subcarrier of the transmit antenna 14 and the transmit antenna 15, respectively, and-C2 and-C1 are transmitted on the 2 nd subcarrier of the transmit antenna 14 and the transmit antenna 15, respectively. Where (), denotes the conjugate of the complex number, and in LTE, OFDM is used for signal transmission.
Referring to fig. 2, fig. 2 is a diagram of a receiving end of a communication system with two receiving antennas in an LTE system according to a preferred embodiment of the present invention. The receiving end receives the coded signal sent by the transmitting end. The receiving end includes a channel decoder 21, a demodulator 22, an SFBC decoder 23, a receiving antenna 24, and a receiving antenna 25. The SFBC decoder 23 decodes the encoded signal received from the transmitter, and then inputs the decoded signal to the demodulator 22 to demodulate the encoded signal to recover the original modulated signal, and then inputs the demodulated modulated signal to the channel decoder 21 to recover the original signal (i.e., the signal sink).
Further, referring to fig. 3, fig. 3 is a flowchart illustrating a method for analyzing space frequency block codes according to a first embodiment of the present invention. In this embodiment, the method for analyzing space frequency block codes includes:
step S10, respectively determining the noise floor of each receiving antenna, wherein the number of the receiving antennas is at least two;
whether any wireless communication receiver is operating properly depends not only on the magnitude of the input signal that can be obtained, but also on the magnitude of its internal noise and external noise and interference. The bottom noise of the receiver is generated by the movement of electrons, the bottom noise of different devices is different, and the bottom noise of different receiving antennas can affect the combination and restoration of signals. The number of receive antennas for which the present invention is directed should be at least two. There are many industry-common calculation methods for the background noise of the receiving antenna, and therefore, the description is not repeated, wherein the calculation method for the background noise of each receiving antenna has the same steps.
Step S20, transforming the frequency domain receiving signals of the receiving antennas according to the bottom noise of each receiving antenna;
the frequency domain received signal of each receiving antenna is transformed based on the noise floor of each receiving antenna determined in step S10. In this embodiment, transforming the frequency domain receiving signals of the receiving antennas can implement not only the integration of the bottom noise parameters of the receiving antennas into the calculation formula of the frequency domain receiving signals, but also the normalization of the bottom noise of each receiving antenna, and all the methods that can implement the above two points can be used as methods for transforming the frequency domain receiving signals by the bottom noise of the receiving antennas.
Step S30, performing space frequency block code decoding according to the transformed frequency domain received signal of each receiving antenna.
SFBC decoding is performed based on the frequency domain received signals of the receiving antennas transformed in step S20, and in this case, the influence of the noise floor of each receiving antenna on SFBC decoding is considered in the algorithm for SFBC analysis, and the noise floor of each receiving antenna is normalized in the calculation process. There are many general calculation methods for analyzing SFBC decoding according to frequency domain signals, and therefore this step is not described again.
In this embodiment, the formula algorithm for decoding the signal codes is obtained by calculating and determining the bottom noise of each receiving antenna, then transforming the frequency domain signal according to the bottom noise of the receiving antenna, and finally performing SFBC decoding according to the transformed frequency signal. In this embodiment, different receiving devices have different corresponding noise floors, which inevitably affects the performance of SFBC decoding. Therefore, the invention realizes the normalization processing of the bottom noise of each receiving antenna by converting the bottom noise of each receiving antenna, thereby further optimizing and improving the SFBC decoding performance and reducing the error rate of the wireless communication system.
Further, referring to fig. 4, fig. 4 is a flowchart illustrating a second embodiment of a method for analyzing space frequency block codes according to the present invention, based on the first embodiment of the method for analyzing space frequency block codes according to the present invention, the method for analyzing space frequency block codes according to the present embodiment includes in the step S10:
step S101, grouping the channel estimation values of each OFDM pilot frequency symbol on the frequency domain signal bandwidth of each receiving antenna, wherein the channel estimation values in each group of channel estimation value groups are the channel estimation values corresponding to the adjacent pilot frequency symbols;
in order to simplify the calculation method and process, in this embodiment, the channel estimation values of the pilot symbols need to be grouped and then calculated in a matrix manner. Wherein, each group of channel estimation values can be composed of two, or four, or six, etc. even number of adjacent channel estimation values.
And step S102, calculating the bottom noise of each receiving antenna according to each group of channel estimation values corresponding to each receiving antenna.
In this embodiment, the channel estimation values of each ofdm pilot symbol in the signal bandwidth of each receiving antenna are grouped, and then the noise floor of each receiving antenna is calculated according to each group of channel estimation values corresponding to each receiving antenna. The steps of the method for calculating the background noise of each receiving antenna are the same. After grouping the channel estimation values of the pilot symbols, a matrix mode can be used to simply and conveniently calculate the process.
Further, referring to fig. 5, fig. 5 is a flowchart illustrating a method for analyzing a space frequency block code according to a third embodiment of the present invention, based on the second embodiment of the method for analyzing a space frequency block code according to the present invention, the method for analyzing a space frequency block code according to the present embodiment includes, in the step S102:
step S1021, calculating conjugate multiplication values corresponding to each group of channel estimation values according to each group of channel estimation values of the receiving antenna;
step S1022, calculating an absolute value of an average value of all conjugate multiplication values according to each conjugate multiplication value;
and calculating the absolute value of the average value of all the conjugate multiplication values according to each conjugate multiplication value to obtain the signal power.
Step S1023, according to the channel estimation value of each orthogonal frequency division multiplexing pilot frequency symbol on the signal bandwidth of each receiving antenna, calculating the power value of each pilot frequency symbol;
step S1024, calculating the average value of the power values of all the pilot symbols according to the power value of each pilot symbol;
and calculating the average value of the power values of all the pilot symbols according to the power value of each pilot symbol to obtain the total power.
Step S1025, calculating the absolute value of the difference between the absolute value of the average value of all the conjugate multiplication values and the average value of the power values of all the pilot symbols, wherein the absolute value of the difference is the noise power value of the receiving antenna;
step S1026, calculating an arithmetic square root of the noise power value of the receiving antenna according to the noise power value of the receiving antenna, where the arithmetic square root is the noise floor of the receiving antenna.
In this embodiment, each set of channel estimation values preferably consists of channel estimation values corresponding to two adjacent pilot symbols. And then calculating conjugate multiplication values of each group of channel estimation values, averaging the conjugate multiplication values, and calculating absolute values to obtain signal power. And solving power values of the channel estimation value of each pilot frequency symbol, and averaging the power values to obtain the total power. The total power is then subtracted from the signal power to obtain the noise power for each receive antenna. The noise power value of the receiving antenna is the square of the bottom noise value of the receiving antenna, so the arithmetic square root of the noise power value of the receiving antenna after the noise power value is squared is the bottom noise value of the receiving antenna. The above-mentioned steps of the calculation method are the steps of calculating the background noise of one receiving antenna, and the steps of the calculation method of the background noise of other receiving antennas are the same.
Further, based on any one of the above first to third embodiment steps S20 of the method for parsing space frequency block code of the present invention, the fourth embodiment of the method for parsing space frequency block code of the present invention comprises at the above step S20: and dividing the frequency domain receiving signal of each receiving antenna by the bottom noise of the receiving antenna to obtain the frequency domain receiving signal transformed by each antenna.
Suppose that the channel coefficients of the transmitting antenna 1 and the transmitting antenna 2 and the receiving antenna 1 are h, respectively11、h21The channel coefficients of the transmitting antenna 1 and the transmitting antenna 2 and the receiving antenna 2 are h12、h22；
The signal of carrier k of receiving antenna 1 is
The signal of carrier k of the receiving antenna 2 is
The signal of the carrier k +1 of the receiving antenna 1 is
The signal of carrier k +1 of receiving antenna 2 is
The transmitted signal of carrier k is xkThe transmission signal of the carrier k +1 is xk+1。
The noise of carrier k of receiving antenna 1 is
The noise of carrier k of receiving antenna 2 is
The noise of the carrier k +1 of the receiving antenna 1 is
The noise of carrier k +1 of receiving antenna 2 is
Then the frequency domain received signal is represented in matrix form as follows:
And converting the received signals of the receiving antennas according to the bottom noise of each antenna, namely dividing the received signals of each antenna by the bottom noise of each antenna, wherein the specific conversion form is as follows:
after the above-mentioned change is performed on the received signal of each receiving antenna, the frequency domain received signal matrix can be represented as follows:
in this embodiment, the received signal of each antenna is divided by the bottom noise of each receiving antenna, so as to transform the frequency domain signal of each receiving antenna, and simultaneously realize normalization processing of the bottom noise of different receiving antennas, and the transformed frequency domain received signal can balance the influence of the bottom noise factors of different receiving antennas on the performance of the SFBC decoding method, so that the estimated value of the original transmitted signal can be decoded with higher quality.
Further, based on any one of the above first to fourth embodiments of the method for parsing space frequency block code of the present invention, step S30, the fifth embodiment of the method for parsing space frequency block code of the present invention comprises at step S30: and performing space frequency block code decoding according to the transformed frequency domain receiving signals of each receiving antenna, and determining a sending signal estimation value of a transmitting antenna corresponding to each receiving antenna.
And performing SFBC decoding according to the frequency domain received signal after the transformation. Because the channel coefficients of the adjacent carriers are not very different, for the convenience of calculation, the channel coefficients of the adjacent carriers are assumed to be the same, namely:
from the above assumptions, a calculation matrix of estimated values of the transmission signal after SFBC decoding can be obtained as follows:
according to the estimation value formula of the SFBC decoded transmission signal, different SFBC coding blocks received by each receiving antenna can be decoded, and thus the estimation value of the restored original transmission signal is finally obtained.
In this embodiment, the influence of different receiving antennas on the analysis of the SFBC coding performance under different background noises is considered, and the SFBC decoding method can be further optimized according to the frequency domain received signals converted by each receiving antenna, so as to obtain a more optimal calculation method for the estimated value of the transmitted signal.
Further, referring to fig. 7, fig. 7 is a functional block diagram of an apparatus for analyzing space frequency block codes according to a first embodiment of the present invention. In this embodiment, the apparatus for resolving space frequency block code includes:
a bottom noise determining module 10, configured to determine the bottom noise of each receiving antenna, where the number of the receiving antennas is at least two;
whether any wireless communication receiver is operating properly depends not only on the magnitude of the input signal that can be obtained, but also on the magnitude of its internal noise and external noise and interference. The bottom noise of the receiver is generated by the movement of electrons, the bottom noise of different devices is different, and the bottom noise of different receiving antennas can affect the combination and restoration of signals. The number of receive antennas for which the present invention is directed should be at least two. There are many industry-common methods for calculating the background noise of a receiving antenna, and therefore, the description thereof is omitted. The steps of the method for calculating the background noise of each receiving antenna are the same.
A frequency domain signal transformation module 20, configured to transform the frequency domain receiving signals of the receiving antennas according to the noise floor of each receiving antenna;
the frequency domain signal transformation module 20 transforms the frequency domain received signals of each receiving antenna according to the bottom noise of each receiving antenna determined by the bottom noise determination module 10. In this embodiment, transforming the frequency domain receiving signals of the receiving antennas can implement not only the integration of the bottom noise parameters of the receiving antennas into the calculation formula of the frequency domain receiving signals, but also the normalization of the bottom noise of each receiving antenna, and all the methods that can implement the above two points can be used as methods for transforming the frequency domain receiving signals by the bottom noise of the receiving antennas.
And a space frequency block code decoding module 30, configured to perform space frequency block code decoding according to the transformed frequency domain receiving signal of each receiving antenna.
The space frequency block code decoding module 30 performs SFBC decoding according to the frequency domain received signals of the receiving antennas transformed by the frequency domain signal transforming module 20, at this time, the influence of the bottom noise of each receiving antenna on the SFBC decoding is considered in the algorithm for analyzing the SFBC, and meanwhile, the bottom noise of each receiving antenna is normalized in the calculation process. There are many general calculation methods for analyzing SFBC decoding according to frequency domain signals, and therefore this step is not described again.
In this embodiment, the bottom noise determining module 10 calculates and determines the bottom noise of each receiving antenna, then the frequency domain signal transforming module 20 transforms the frequency domain signal according to the bottom noise of the receiving antenna, and finally the space frequency block code decoding module 30 performs SFBC decoding according to the transformed frequency signal, so as to obtain a formula algorithm for decoding the signal code. In this embodiment, different receiving devices have different corresponding noise floors, which inevitably affects the performance of SFBC decoding. Therefore, the invention realizes the normalization processing of the bottom noise of each receiving antenna by converting the bottom noise of each receiving antenna, thereby further optimizing and improving the SFBC decoding performance and reducing the error rate of the wireless communication system.
Further, referring to fig. 8, fig. 8 is a functional block diagram of a second embodiment of the apparatus for analyzing space frequency block codes according to the present invention, and based on the first embodiment of the apparatus for analyzing space frequency block codes according to the present invention, the noise floor determination module 10 of the apparatus for analyzing space frequency block codes according to the present embodiment includes:
a grouping submodule 101, configured to group channel estimation values of each orthogonal frequency division multiplexing pilot symbol in the frequency domain signal bandwidth of each receiving antenna, where a channel estimation value in each channel estimation value group is a channel estimation value corresponding to an adjacent pilot symbol;
in order to simplify the calculation method and process, in this embodiment, the grouping unit 101 needs to group the channel estimation values of the pilot symbols and then calculate the channel estimation values in a matrix manner. Wherein, each group of channel estimation values can be composed of two, or four, or six channel estimation values of even number adjacent pilot frequency symbols.
And a bottom noise calculation sub-module 102, configured to calculate a bottom noise of each receiving antenna according to each set of channel estimation values corresponding to each receiving antenna.
In this embodiment, the grouping unit 101 groups the channel estimation values of each ofdm pilot symbol in the signal bandwidth of each receiving antenna, and then the background noise calculation unit 102 calculates the background noise of each receiving antenna according to each group of channel estimation values corresponding to each receiving antenna. The steps of the method for calculating the background noise of each receiving antenna are the same. After grouping the channel estimation values of the pilot symbols, a matrix mode can be used to simply and conveniently calculate the process.
Further, referring to fig. 9, fig. 9 is a functional block diagram of a device for analyzing space frequency block codes according to a third embodiment of the present invention, and based on the second embodiment of the device for analyzing space frequency block codes according to the present invention, the bottom noise calculating sub-module 102 of the present embodiment includes:
a conjugate multiplication value calculation unit 1021, configured to calculate a conjugate multiplication value corresponding to each group of channel estimation values according to each group of channel estimation values of the receiving antenna;
a first calculating unit 1022, configured to calculate an absolute value of an average value of all conjugate multiplication values according to each conjugate multiplication value;
and calculating the absolute value of the average value of all the conjugate multiplication values according to each conjugate multiplication value to obtain the signal power.
A pilot symbol power value calculation unit 1023, configured to calculate a power value of each pilot symbol according to a channel estimation value of each orthogonal frequency division multiplexing pilot symbol on each receiving antenna signal bandwidth;
a second calculating unit 1024, configured to calculate an average value of the power values of all pilot symbols according to the power value of each pilot symbol;
and calculating the average value of the power values of all the pilot symbols according to the power value of each pilot symbol to obtain the total power.
A receiving antenna noise power value calculation unit 1025 for calculating an absolute value of a difference between an absolute value of an average value of all the conjugate multiplication values and an average value of power values of all the pilot symbols, the absolute value of the difference being a noise power value of a receiving antenna;
a receiving antenna bottom noise calculating unit 1026, configured to calculate an arithmetic square root of the noise power value of the receiving antenna according to the noise power value of the receiving antenna, where the arithmetic square root is the bottom noise of the receiving antenna.
In this embodiment, each set of channel estimation values preferably consists of channel estimation values corresponding to two adjacent pilot symbols. And then calculating conjugate multiplication values of each group of channel estimation values, averaging the conjugate multiplication values, and calculating absolute values to obtain signal power. And solving power values of the channel estimation value of each pilot frequency symbol, and averaging the power values to obtain the total power. The total power is then subtracted from the signal power to obtain the noise power for each receive antenna. The noise power value of the receiving antenna is the square of the bottom noise value of the receiving antenna, so the arithmetic square root of the noise power value of the receiving antenna after the noise power value is squared is the bottom noise value of the receiving antenna. The above-mentioned steps of the calculation method are the steps of calculating the background noise of one receiving antenna, and the steps of the calculation method of the background noise of other receiving antennas are the same.
Further, based on the frequency domain signal transformation module 20 in any one of the first to third embodiments of the apparatus for analyzing a space frequency block code according to the present invention, the frequency domain signal transformation module 20 in the fourth embodiment of the apparatus for analyzing a space frequency block code according to the present invention is further configured to divide the frequency domain received signal of each receiving antenna by the noise floor of the receiving antenna, so as to obtain the frequency domain received signal after each antenna is transformed.
Suppose that the channel coefficients of the transmitting antenna 1 and the transmitting antenna 2 and the receiving antenna 1 are h, respectively11、h21The channel coefficients of the transmitting antenna 1 and the transmitting antenna 2 and the receiving antenna 2 are h12、h22；
The signal of carrier k of receiving antenna 1 is
The signal of carrier k of the receiving antenna 2 is
The signal of the carrier k +1 of the receiving antenna 1 is
The signal of carrier k +1 of receiving antenna 2 is
The transmitted signal of carrier k is xkThe transmission signal of the carrier k +1 is xk+1。
The noise of carrier k of receiving antenna 1 is
The noise of carrier k of receiving antenna 2 is
The noise of the carrier k +1 of the receiving antenna 1 is
The noise of carrier k +1 of receiving antenna 2 is
Then the frequency domain received signal is represented in matrix form as follows:
And converting the received signals of the receiving antennas according to the bottom noise of each antenna, namely dividing the received signals of each antenna by the bottom noise of each antenna, wherein the specific conversion form is as follows:
after the above-mentioned change is performed on the received signal of each receiving antenna, the frequency domain received signal matrix can be represented as follows:
in this embodiment, the received signal of each antenna is divided by the bottom noise of each receiving antenna, so as to transform the frequency domain signal of each receiving antenna, and simultaneously realize normalization processing of the bottom noise of different receiving antennas, and the transformed frequency domain received signal can balance the influence of the bottom noise factors of different receiving antennas on the performance of the SFBC decoding method, so that the estimated value of the original transmitted signal can be decoded with higher quality.
Further, based on the space frequency block code decoding module 30 in any one of the first to fourth embodiments of the apparatus for analyzing a space frequency block code according to the present invention, the space frequency block code decoding module 30 in the fifth embodiment of the apparatus for analyzing a space frequency block code according to the present invention is further configured to perform space frequency block code decoding according to the transformed frequency domain receiving signal of each receiving antenna, and determine the transmitting signal estimation value of the transmitting antenna corresponding to each receiving antenna.
And performing SFBC decoding according to the frequency domain received signal after the transformation. Because the channel coefficients of the adjacent carriers are not very different, for the convenience of calculation, the channel coefficients of the adjacent carriers are assumed to be the same, namely:
from the above assumptions, a calculation matrix of estimated values of the transmission signal after SFBC decoding can be obtained as follows:
according to the estimation value formula of the SFBC decoded transmission signal, different SFBC coding blocks received by each receiving antenna can be decoded, and thus the estimation value of the restored original transmission signal is finally obtained.
In this embodiment, the influence of different receiving antennas on the analysis of the SFBC coding performance under different background noises is considered, and the SFBC decoding method can be further optimized according to the frequency domain received signals converted by each receiving antenna, so as to obtain a more optimal calculation method for the estimated value of the transmitted signal.
Referring to fig. 10, fig. 10 is a diagram illustrating comparison of performance of the conventional SFBC analysis method (Original) and the SFBC analysis method (New) according to the present invention. Wherein, the simulation channel is AWGN, the simulation bandwidth is 10M, and the difference between the bottom noises of the receiving antenna 0 and the receiving antenna 1 is 5 dB. According to the figure, under the condition that the bottom noises of the two receiving antennas are unbalanced, the decoding performance of the SFBC analysis new algorithm is improved by about 1.5dB compared with the original algorithm, so that the SFBC analysis new algorithm optimized by the invention has obvious performance improvement under the condition that the bottom noises of the receiving antennas are different and unbalanced.
The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (4)
1. A method for resolving space frequency block codes, the method comprising:
respectively determining the background noise of each receiving antenna, wherein the number of the receiving antennas is at least two;
transforming the frequency domain receiving signals of the receiving antennas according to the bottom noise of each receiving antenna;
performing space frequency block code decoding according to the transformed frequency domain receiving signals of each receiving antenna;
wherein the separately determining the noise floor for each receive antenna comprises:
grouping the channel estimation values of each orthogonal frequency division multiplexing pilot frequency symbol on the frequency domain signal bandwidth of each receiving antenna, wherein the channel estimation values in each group of channel estimation value groups are the channel estimation values corresponding to the adjacent pilot frequency symbols;
calculating the bottom noise of each receiving antenna according to each group of channel estimation values corresponding to each receiving antenna;
wherein the calculating the noise floor of each receiving antenna according to the respective sets of channel estimation values corresponding to each receiving antenna comprises:
calculating conjugate multiplication values corresponding to each group of channel estimation values according to each group of channel estimation values of the receiving antenna;
calculating the absolute value of the average value of all the conjugate multiplication values according to each conjugate multiplication value;
calculating the power value of each pilot frequency symbol according to the channel estimation value of each orthogonal frequency division multiplexing pilot frequency symbol on the signal bandwidth of each receiving antenna;
calculating the average value of the power values of all the pilot symbols according to the power value of each pilot symbol;
calculating the absolute value of the difference between the absolute value of the average value of all the conjugate multiplication values and the average value of the power values of all the pilot symbols, wherein the absolute value of the difference is the noise power value of the receiving antenna;
calculating the arithmetic square root of the noise power value of the receiving antenna according to the noise power value of the receiving antenna, wherein the arithmetic square root is the bottom noise of the receiving antenna;
wherein the transforming the frequency domain received signals of the receiving antennas according to the noise floor of each receiving antenna comprises:
and dividing the frequency domain receiving signal of each receiving antenna by the bottom noise of the receiving antenna to obtain the frequency domain receiving signal transformed by each antenna.
2. The method of parsing space-frequency block code according to claim 1, wherein said decoding space-frequency block code according to the transformed frequency-domain received signal of each receiving antenna comprises:
and performing space frequency block code decoding according to the transformed frequency domain receiving signals of each receiving antenna, and determining a sending signal estimation value of a transmitting antenna corresponding to each receiving antenna.
3. An apparatus for resolving space frequency block codes, the apparatus comprising:
a bottom noise determining module, configured to determine the bottom noise of each receiving antenna, where the number of the receiving antennas is at least two;
the frequency domain signal transformation module is used for transforming the frequency domain receiving signals of the receiving antennas according to the bottom noise of each receiving antenna;
a space frequency block code decoding module, configured to perform space frequency block code decoding according to the transformed frequency domain receiving signal of each receiving antenna;
wherein the noise floor determination module comprises:
a grouping submodule, configured to group channel estimation values of each orthogonal frequency division multiplexing pilot symbol in the frequency domain signal bandwidth of each receiving antenna, where a channel estimation value in each channel estimation value group is a channel estimation value corresponding to an adjacent pilot symbol;
a bottom noise calculation submodule, configured to calculate a bottom noise of each receiving antenna according to each set of channel estimation values corresponding to each receiving antenna;
wherein the bottom noise calculation sub-module includes:
a conjugate multiplication value calculating unit, configured to calculate, according to each group of channel estimation values of the receiving antenna, a conjugate multiplication value corresponding to each group of channel estimation values;
a first calculating unit for calculating an absolute value of an average value of all the conjugate multiplication values according to each of the conjugate multiplication values;
a pilot symbol power value calculation unit, configured to calculate a power value of each pilot symbol according to a channel estimation value of each ofdm pilot symbol on a signal bandwidth of each receiving antenna;
a second calculating unit, configured to calculate an average value of the power values of all pilot symbols according to the power value of each pilot symbol;
a receiving antenna noise power value calculating unit, configured to calculate an absolute value of a difference between an absolute value of an average value of all the conjugate multiplication values and an average value of power values of all the pilot symbols, where the absolute value of the difference is a noise power value of a receiving antenna;
a receiving antenna bottom noise calculating unit, configured to calculate an arithmetic square root of the noise power value of the receiving antenna according to the noise power value of the receiving antenna, where the arithmetic square root is the bottom noise of the receiving antenna;
wherein the frequency domain signal transformation module is further configured to: and dividing the frequency domain receiving signal of each receiving antenna by the bottom noise of the receiving antenna to obtain the frequency domain receiving signal transformed by each antenna.
4. The apparatus for parsing space-frequency block code according to claim 3, wherein the space-frequency block code decoding module is further configured to:
and performing space frequency block code decoding according to the transformed frequency domain receiving signals of each receiving antenna, and determining a sending signal estimation value of a transmitting antenna corresponding to each receiving antenna.
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| CN201410764648.6A CN105743608B (en) | 2014-12-11 | 2014-12-11 | Method and device for analyzing space frequency block code |
| PCT/CN2015/077734 WO2016090818A1 (en) | 2014-12-11 | 2015-04-28 | Method and device for parsing spatial frequency block code and storage medium |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101478524A (en) * | 2009-01-22 | 2009-07-08 | 清华大学 | Correction method for phase noise of multi-antenna OFDM system receiving terminal |
| CN102025426A (en) * | 2009-09-17 | 2011-04-20 | 中兴通讯股份有限公司 | Method and device for estimating carrier to interference plus noise ratio in orthogonal frequency division multiplexing system |
| EP2315404A1 (en) * | 2009-10-26 | 2011-04-27 | ST-Ericsson (France) SAS | Process for decoding ALAMOUTI block code in an OFDM system, and receiver for the same |
| CN102710577A (en) * | 2012-06-15 | 2012-10-03 | 上海大学 | High-speed movement-based intercarrier interference (ICI) eliminating and decoding method for space frequency block coding (SFBC) coordinated orthogonal frequency division multiplexing (OFDM) system |
| CN102820935A (en) * | 2011-06-08 | 2012-12-12 | 上海无线通信研究中心 | Method for detecting Almouti code in an MIMO (multi-input multi-output)-OFDM (orthogonal frequency division multiplexing) system |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100754617B1 (en) * | 2004-10-11 | 2007-09-05 | 삼성전자주식회사 | Apparatus and method for minimizing peak to average power ratio in orthogonal frequency division multiplexing communication system |
| WO2007106366A2 (en) * | 2006-03-10 | 2007-09-20 | Interdigital Technology Corporation | Method and apparatus for scaling soft bits for decoding |
| US20100119017A1 (en) * | 2008-11-10 | 2010-05-13 | Joonsuk Kim | Method and system for a 4x2 sfbc/stbc system with 2 spatial streams using angle feedback |
| CN101494491B (en) * | 2009-03-04 | 2013-04-17 | 北京邮电大学 | Method and apparatus for processing acceptance signal of multiaerial system |
-
2014
- 2014-12-11 CN CN201410764648.6A patent/CN105743608B/en active Active
-
2015
- 2015-04-28 WO PCT/CN2015/077734 patent/WO2016090818A1/en active Application Filing
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101478524A (en) * | 2009-01-22 | 2009-07-08 | 清华大学 | Correction method for phase noise of multi-antenna OFDM system receiving terminal |
| CN102025426A (en) * | 2009-09-17 | 2011-04-20 | 中兴通讯股份有限公司 | Method and device for estimating carrier to interference plus noise ratio in orthogonal frequency division multiplexing system |
| EP2315404A1 (en) * | 2009-10-26 | 2011-04-27 | ST-Ericsson (France) SAS | Process for decoding ALAMOUTI block code in an OFDM system, and receiver for the same |
| CN102820935A (en) * | 2011-06-08 | 2012-12-12 | 上海无线通信研究中心 | Method for detecting Almouti code in an MIMO (multi-input multi-output)-OFDM (orthogonal frequency division multiplexing) system |
| CN102710577A (en) * | 2012-06-15 | 2012-10-03 | 上海大学 | High-speed movement-based intercarrier interference (ICI) eliminating and decoding method for space frequency block coding (SFBC) coordinated orthogonal frequency division multiplexing (OFDM) system |
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