CN102281127B - A kind of method for transmitting signals, system and transmitter and receiver - Google Patents

Abstract

The invention discloses a kind of method for transmitting signals, comprising: the translational speed pattern that transmitter is current according to receiver feedback information determination receiver; When described translational speed pattern is low speed Move Mode, the coded system of coherent transmission mode is adopted to encode to signal to be sent, when described Move Mode is high-speed mobile pattern, the coded system of noncoherent transmission modes is adopted to encode to signal to be sent; Signal after coding is sent to receiver.In addition, the invention also discloses a kind of signal transmission system and transmitter and receiver.Technical scheme disclosed in this invention, can make wireless transmission all have good systematic function under different mobile environment.

Description

A kind of method for transmitting signals, system and transmitter and receiver

Technical field

The present invention relates to wireless communication technology, particularly relate to a kind of method for transmitting signals, system and transmitter and receiver.

Background technology

Along with the development of wireless communication technology, the validity and reliability of people to wireless transmission is had higher requirement.Multi-antenna technology, owing to can make full use of the Multipath Transmission in radio transmission, makes the availability of frequency spectrum and link reliability be greatly improved, is therefore widely applied.

When considering that signal transmits in wireless channel, can be subject to the impact of wireless channel fading effect, therefore, in multi-antenna technology application, the coded excitation adopting coherent transfer detection technique to carry out signal is resolved with reception more.Coherent transfer detection technique combines the diversity gain of multiple antennas and the coding gain of chnnel coding, can under the prerequisite not reducing data transmission rate, and the fading effect of effective antagonism wireless channel, realizes the transmitting of data.But relevant detection needs to obtain accurate channel estimating, when there is larger relative velocity in transmitting terminal and receiving terminal, as under high-speed mobile environment, because coherence time is less, when inadequate for the pilot sequence density of channel estimating, precision of channel estimation can reduce greatly, and then causes performance loss larger.If but use a large amount of pilot frequency sequence, then can reduce system spectral efficiency again, and under low speed mobile environment, use a large amount of pilot frequency sequences to be also a kind of waste, make the cost of channel estimating become very large.So, to adopting the system of coherent transfer detection to be a kind of challenge under high-speed mobile environment.

For this reason, in multi-antenna technology application, also there is a kind of incoherent transmission detection technique.Incoherent detection does not need channel estimating, and therefore not by the impact of high-speed mobile environment, and owing to not needing channel information, incoherent transmission is detected does not need extra pilot-frequency expense.But there is performance loss compared with incoherent transmission detection detects with coherent transfer, and the decoding complex degree of incoherent detection is very high, usually with transmitting antenna and constellation sizes exponential increase, this in turn limits the application that incoherent transmission detects.

For this reason, how making under different mobile environment, all have good systematic function is the problem that current wireless transmission needs to solve.

Summary of the invention

In view of this, provide a kind of method for transmitting signals on the one hand in the present invention, provide a kind of signal transmission system and transmitter and machine to receive machine, so that wireless transmission all has good systematic function under different mobile environment on the other hand.

Method for transmitting signals provided by the present invention, comprising:

The translational speed pattern that transmitter determination receiver is current;

When described translational speed pattern is low speed Move Mode, the coded system of coherent transmission mode is adopted to encode to signal to be sent, when described translational speed pattern is high-speed mobile pattern, the coded system of noncoherent transmission modes is adopted to encode to signal to be sent;

Signal after coding is sent to receiver;

The coded system of described employing noncoherent transmission modes is carried out coding to signal to be sent and is comprised:

Determine selectivity of channel frequency, when described selectivity of channel frequency is strong, when adopting the first difference empty, coding mode is treated and is sent signal and encode; When described selectivity of channel frequency is weak, when adopting the first difference empty, when coding mode or the second difference empty, coding mode is treated and is sent signal and encode;

During the first difference empty of described employing, coding mode is treated and is sent signal and carry out coding and comprise:

Input two-way information bit, carries out Alamouti differential space-time coding to described two-way information bit, obtains code signal s ₁and s ₂;

To described code signal s ₁and s ₂carry out Alamouti Space Time Coding, obtain space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate;

Utilize encoder matrix W _{m × 2}, by described space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right)$ Expand to M transmit antennas, obtain the matrix that transmits $\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ ...& ...\\ d_{M1}& d_{M2}\end{array}\right),$ Wherein, W be M × M unitary matrix any two row, M be more than or equal to 2 arbitrary integer;

During described employing the second difference empty, coding mode is treated and is sent signal and carry out coding and comprise:

Corresponding N transmit antennas pre-sets N/2 Alamouti differential space-time coding unit, N be more than or equal to 2 even number;

Corresponding each Alamouti differential space-time coding unit inputs two-way information bit respectively, and each Alamouti differential space-time coding unit carries out Alamouti differential space-time coding to the two-way information bit of input self respectively, obtains code signal s ₁, s ₂..., s _n-1, s _n;

To described code signal s ₁, s ₂..., s _n-1, s _ncarry out space-frequency block codes SFBC+ frequency error factor transmitting diversity FSTD Space Time Coding, obtain the matrix that transmits $\left(\begin{array}{ccccc}{s}_1& -s_2^{*}& ...& 0& 0\\ s_2& s_1^{*}& ...& 0& 0\\ ...& ...& ...& ...& ...\\ 0& 0& ...& s_{N-1}& -s_N^{*}\\ 0& 0& ...& s_N& s_{N-1}^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate.

Signal transmission system provided by the present invention, comprising: transmitter and receiver;

Described transmitter is for determining the translational speed pattern that receiver is current, when described translational speed pattern is low speed Move Mode, the coded system of coherent transmission mode is adopted to encode to signal to be sent, when described translational speed pattern is high-speed mobile pattern, adopt the coded system of noncoherent transmission modes to encode to signal to be sent, the signal after coding is sent to described receiver;

Described receiver, for receiving the signal from described transmitter, utilizes the decoding process corresponding with coded system to decode to received signal;

The coded system of described employing noncoherent transmission modes is carried out coding to signal to be sent and is comprised:

Determine selectivity of channel frequency, when described selectivity of channel frequency is strong, when adopting the first difference empty, coding mode is treated and is sent signal and encode; When described selectivity of channel frequency is weak, when adopting the first difference empty, when coding mode or the second difference empty, coding mode is treated and is sent signal and encode;

During the first difference empty of described employing, coding mode is treated and is sent signal and carry out coding and comprise:

Input two-way information bit, carries out Alamouti differential space-time coding to described two-way information bit, obtains code signal s ₁and s ₂;

To described code signal s ₁and s ₂carry out Alamouti Space Time Coding, obtain space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate;

Utilize encoder matrix W _{m × 2}, by described space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right)$ Expand to M transmit antennas, obtain the matrix that transmits $\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ ...& ...\\ d_{M1}& d_{M2}\end{array}\right),$ Wherein, W be M × M unitary matrix any two row, M be more than or equal to 2 arbitrary integer;

During described employing the second difference empty, coding mode is treated and is sent signal and carry out coding and comprise:

Corresponding N transmit antennas pre-sets N/2 Alamouti differential space-time coding unit, N be more than or equal to 2 even number;

Corresponding each Alamouti differential space-time coding unit inputs two-way information bit respectively, and each Alamouti differential space-time coding unit carries out Alamouti differential space-time coding to the two-way information bit of input self respectively, obtains code signal s ₁, s ₂..., s _n-1, s _n;

To described code signal s ₁, s ₂..., s _n-1, s _ncarry out space-frequency block codes SFBC+ frequency error factor transmitting diversity FSTD Space Time Coding, obtain the matrix that transmits $\left(\begin{array}{ccccc}{s}_1& -s_2^{*}& ...& 0& 0\\ s_2& s_1^{*}& ...& 0& 0\\ ...& ...& ...& ...& ...\\ 0& 0& ...& s_{N-1}& -s_N^{*}\\ 0& 0& ...& s_N& s_{N-1}^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate.

Transmitter provided by the present invention, comprising:

Velocity mode determination module, for determining that the current translational speed pattern of receiver is low speed Move Mode or high-speed mobile pattern;

First coding module, when the translational speed pattern for determining at described velocity mode determination module is low speed Move Mode, adopts the coded system of coherent transmission mode to encode to signal to be sent;

Second coding module, when the translational speed pattern for determining at described velocity mode determination module is high-speed mobile pattern, adopts the coded system of noncoherent transmission modes to encode to signal to be sent;

Signal transmitting module, for sending to receiver by the signal after described first coding module or the second coding module coding;

Described second coding module comprises: selectivity of channel frequency determination module, the first modulation module, the first precoding module, the second modulation module and the second precoding module;

Described selectivity of channel frequency determination module is used for determining selectivity of channel frequency, when selectivity of channel frequency is strong, notifies that the first modulation module and the first precoding module are treated code signal and encoded; When selectivity of channel frequency is weak, notify that the first modulation module and the first precoding module or the second modulation module and the second precoding module are treated code signal and encoded;

First modulation module, for carrying out Alamouti differential space-time coding to the two-way information bit of current input, obtains code signal s ₁and s ₂;

First precoding module, for the code signal s obtained described first modulation module ₁and s ₂carry out Alamouti Space Time Coding, obtain space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right),$ Utilize encoder matrix W _{m × 2}, by described space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right)$ Expand to M transmit antennas, obtain the matrix that transmits $\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ ...& ...\\ d_{M1}& d_{M2}\end{array}\right),$ Wherein, W be M × M unitary matrix any two row, M be more than or equal to 2 arbitrary integer, subscript * represents complex conjugate;

Second modulation module, comprise N/2 the Alamouti differential space-time coding unit that corresponding N transmit antennas pre-sets, each Alamouti differential space-time coding unit carries out Alamouti differential space-time coding to the two-way information bit of input self respectively, obtains code signal s ₁, s ₂..., s _n-1, s _n; Wherein, N be more than or equal to 2 even number;

Second precoding module, for described code signal s ₁, s ₂..., s _n-1, s _ncarry out space-frequency block codes SFBC+ frequency error factor transmitting diversity FSTD Space Time Coding, obtain the matrix that transmits $\left(\begin{array}{ccccc}{s}_1& -s_2^{*}& ...& 0& 0\\ s_2& s_1^{*}& ...& 0& 0\\ ...& ...& ...& ...& ...\\ 0& 0& ...& s_{N-1}& -s_N^{*}\\ 0& 0& ...& s_N& s_{N-1}^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate;

The coded system that described signal transmitting module is further used for the signal after by described coding corresponding is indicated to receiver.

Receiver provided by the present invention, comprising:

Signal receiving module, for receiving the signal from transmitter, when the coded system determining described signal is the coded system of coherent transmission mode, the first decoder module is given by described Signal transmissions, when the coded system determining described signal is the coded system of noncoherent transmission modes, give the second decoder module by described Signal transmissions;

First decoder module, for the signal transmitted described signal receiving module, adopts the decoding process of relevant detecting pattern to decode;

Second decoder module, for the signal transmitted described signal receiving module, adopts the decoding process of noncoherent detection modes to decode;

The coded system of described employing noncoherent transmission modes is: when determining that selectivity of channel frequency is strong, coding mode when adopting the first difference empty; When determining that selectivity of channel frequency is weak, coding mode when coding mode or the second difference empty when adopting the first difference empty;

During the first difference empty described, coding mode comprises:

Input two-way information bit, carries out Alamouti differential space-time coding to described two-way information bit, obtains code signal s ₁and s ₂;

To described code signal s ₁and s ₂carry out Alamouti Space Time Coding, obtain space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate;

Utilize encoder matrix W _{m × 2}, by described space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right)$ Expand to M transmit antennas, obtain the matrix that transmits $\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ ...& ...\\ d_{M1}& d_{M2}\end{array}\right),$ Wherein, W be M × M unitary matrix any two row, M be more than or equal to 2 arbitrary integer;

During described the second difference empty, coding mode comprises:

Corresponding N transmit antennas pre-sets N/2 Alamouti differential space-time coding unit, N be more than or equal to 2 even number;

Corresponding each Alamouti differential space-time coding unit inputs two-way information bit respectively, and each Alamouti differential space-time coding unit carries out Alamouti differential space-time coding to the two-way information bit of input self respectively, obtains code signal s ₁, s ₂..., s _n-1, s _n;

To described code signal s ₁, s ₂..., s _n-1, s _ncarry out space-frequency block codes SFBC+ frequency error factor transmitting diversity FSTD Space Time Coding, obtain the matrix that transmits $\left(\begin{array}{ccccc}{s}_1& -s_2^{*}& ...& 0& 0\\ s_2& s_1^{*}& ...& 0& 0\\ ...& ...& ...& ...& ...\\ 0& 0& ...& s_{N-1}& -s_N^{*}\\ 0& 0& ...& s_N& s_{N-1}^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate.

As can be seen from such scheme, translational speed that can be different according to receiver in the embodiment of the present invention, adopts different coded systems to encode to data to be sent, thus achieves adaptive Signal transmissions.And in this adaptive signal transmission scheme, by under low speed mobile environment, adopt the coherent transfer detection technique with better performance, and under high-speed mobile environment, adopt the incoherent transmission detection technique without the need to channel estimating, make the technical scheme in the embodiment of the present invention can obtain good performance under different mobile environment.

In addition, by providing the difference empty time-code after two kinds of simplification in the embodiment of the present invention, when making to adopt incoherent transmission detection technique under high-speed mobile environment, the complexity of decoding can be reduced.

Accompanying drawing explanation

Fig. 1 is the exemplary process diagram of method for transmitting signals in the embodiment of the present invention;

The schematic diagram of code method when Fig. 2 is the first difference empty in the embodiment of the present invention;

Fig. 3 is the schematic diagram of code method when illustrating the first difference empty in the embodiment of the present invention;

The schematic diagram of code method when Fig. 4 is the second difference empty in the embodiment of the present invention;

Fig. 5 is the schematic diagram of code method when illustrating the second difference empty in the embodiment of the present invention;

Fig. 6 is the exemplary block diagram of signal transmission system in the embodiment of the present invention.

Embodiment

For making the object, technical solutions and advantages of the present invention clearly understand, below in conjunction with embodiment and accompanying drawing, the present invention is described in more detail.

Fig. 1 is the exemplary process diagram of method for transmitting signals in the embodiment of the present invention.As shown in Figure 1, this flow process comprises the steps:

Step 101, the translational speed pattern that transmitter determination receiver is current, when described translational speed pattern is low speed Move Mode, performs step 102; When described Move Mode is high-speed mobile pattern, perform step 103.

In this step, can be low speed Move Mode and high-speed mobile pattern by the translational speed mode division of receiver.When specifically determining the translational speed pattern of receiver, can be determined alternately by Receiver And Transmitter, the translational speed pattern that now transmitter can be current according to the feedback information determination receiver of receiver.Or also transmitter can be assisted to determine by third party's module.Wherein, when being determined alternately by Receiver And Transmitter, the following two kinds determination mode can be had at least.

Mode one:

The current translational speed of receiver detection self, the current translational speed detected and the threshold speed preset are compared, if described current translational speed is higher than described threshold speed, then determine that self current translational speed pattern is high-speed mobile pattern, otherwise determine that self current translational speed pattern is low speed Move Mode, determined current translational speed pattern is indicated to transmitter; Transmitter, according to the instruction of described receiver, determines the translational speed pattern that receiver is current.

Wherein, when determined current translational speed pattern is indicated to transmitter by receiver, in order to save system resource, can adopt the information of 1 bit that determined current translational speed pattern is indicated to transmitter.As, utilize 1 expression low speed Move Mode, 0 represents high-speed mobile pattern.

Mode two:

The current translational speed of receiver detection self, is indicated to transmitter by detected current translational speed; The current translational speed that receiver detects by transmitter compares with the threshold speed preset, if described current translational speed is higher than described threshold speed, then determine that the current translational speed pattern of receiver is high-speed mobile pattern, otherwise determine that the current translational speed pattern of receiver is low speed Move Mode.

In above-mentioned two kinds of modes, receiver periodically can detect the current translational speed of self according to predetermined period, or also can detect the current translational speed of self when the trigger condition of satisfied setting.

Step 102, adopts the coded system of coherent transmission mode to encode to signal to be sent.

In this step, the coded system of coherent transmission mode can be the coded system of any coherent transmission mode of the prior art, as Space Time Coding, places, complete Space Time Coding after namely modulating the information bit of input according to space-time code coding method.

In addition, the coded system of coherent transmission mode also can be the coded system of newly-increased various coherent transmission mode.

Step 103, adopts the coded system of noncoherent transmission modes to encode to signal to be sent.

In this step, the coded system of noncoherent transmission modes can be the coded system of any incoherent sending mode of the prior art, as various difference empty time-codes of the prior art etc.

In addition, the coded system of noncoherent transmission modes also can be the coded system of newly-increased various noncoherent transmission modes.

Step 104, sends to receiver by the signal after coding.

Receiver, after receiving the signal after from transmitter coding, utilizes the decoding process corresponding with coded system to decode to the signal after described coding.

During specific implementation, if the coded system of the coded system of coherent transmission mode and noncoherent transmission modes only has a kind of coded system selective respectively, then the coded system that receiver can be corresponding according to self determined current translational speed pattern determination received signal.Or translational speed pattern corresponding for Signal coding or coded system also can be indicated to receiver by transmitter, and receiver determines according to the described instruction of transmitter the coded system that received signal is corresponding.Such as, transmitter can provide an indication information in downstream signal, so that the coded system that present encoding adopts to be described.

If the coded system of coherent transmission mode has more than a kind of coded system, coded system that is selective and/or noncoherent transmission modes has more than a kind of coded system selective, then by transmitter, coded system corresponding for Signal coding can be indicated to receiver, receiver determines according to the described instruction of transmitter the coded system that received signal is corresponding.Such as, transmitter can provide an indication information in downstream signal, so that the coded system that present encoding adopts to be described.

In the embodiment of the present invention, in order to reduce the decoding complex degree of incoherent detection, consider that Alamouti space-time code code check is higher, simultaneously have again larger diversity gain and lower decoding complex degree, in above-mentioned steps 103 again based on Alamouti space-time code provide two kinds simplify difference empty time code method.

The schematic diagram of code method when Fig. 2 is the first difference empty in the embodiment of the present invention.As shown in Figure 2, the cataloged procedure of the first difference empty time-code comprises:

Input two-way information bit, modulates described two-way information bit, namely carries out Alamouti differential space-time coding to described two-way information bit, obtain code signal s ₁and s ₂.

To described code signal s ₁and s ₂carry out the precoding processing comprising space-frequency block codes (SFBC) and matrix mapping, namely to described code signal s ₁and s ₂carry out Alamouti Space Time Coding, obtain space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right),$ Utilize encoder matrix W _{m × 2}, by described space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right)$ Expand to M transmit antennas, obtain the matrix that transmits $\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ ...& ...\\ d_{M1}& d_{M2}\end{array}\right).$ Wherein, subscript * represents complex conjugate, W be M × M unitary matrix any two row, M be more than or equal to 2 arbitrary integer.

Below for two-phase PSK (BPSK) modulation and the situation of four transmit antennas, said process is illustrated.As shown in Figure 3, cataloged procedure comprises:

Input information bits a ₁and a ₂carry out Alamouti differential space-time coding, obtain code signal s ₁and s ₂.Then to code signal s ₁and s ₂carry out Alamouti Space Time Coding, obtain $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right).$ Afterwards, encoder matrix W is used _{4 × 2}alamouti space-time code is expanded to 4 transmit antennas, obtains the matrix that transmits $\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ d_{31}& d_{32}\\ d_{41}& d_{42}\end{array}\right).$

Above-mentioned visible, when adopting BPSK modulation, each input two information bits, then input four information bits when adopting quarternary phase-shift keying (QPSK) (QPSK) to modulate, two, Ji Mei road information bit at every turn.

The schematic diagram of code method when Fig. 4 is the second difference empty in the embodiment of the present invention.As shown in Figure 4, the cataloged procedure of the second difference empty time-code comprises:

Corresponding N transmit antennas pre-sets N/2 Alamouti differential space-time coding unit, wherein, N be more than or equal to 2 even number.

Corresponding each Alamouti differential space-time coding unit inputs two-way information bit respectively, each road information bit of input is modulated, namely each Alamouti differential space-time coding unit carries out Alamouti differential space-time coding to the two-way information bit of input self respectively, obtains code signal s ₁, s ₂..., s _n-1, s _n.

To described code signal s ₁, s ₂..., s _n-1, s _ncarry out space-frequency block codes SFBC+ frequency error factor transmitting diversity FSTD Space Time Coding, i.e. precoding, obtains the matrix that transmits $\left(\begin{array}{ccccc}{s}_1& -s_2^{*}& ...& 0& 0\\ s_2& s_1^{*}& ...& 0& 0\\ ...& ...& ...& ...& ...\\ 0& 0& ...& s_{N-1}& -s_N^{*}\\ 0& 0& ...& s_N& s_{N-1}^{*}\end{array}\right).$ Wherein, subscript * represents complex conjugate.

Below still for BPSK modulation and the situation of four transmit antennas, said process is illustrated.As shown in Figure 5, cataloged procedure comprises:

Corresponding 4 transmit antennas pre-set 2 Alamouti differential space-time coding unit.

Input information bits a ₁and a ₂carry out Alamouti differential space-time coding, obtain code signal s ₁and s ₂.Input information bits a ₃and a ₄carry out Alamouti differential space-time coding, obtain code signal s ₃and s ₄.Then to code signal s ₁, s ₂, s ₃and s ₄carry out SFBC+FSTD Space Time Coding, obtain the matrix that transmits $\left(\begin{array}{cccc}{s}_1& -s_2^{*}& 0& 0\\ s_2& s_1^{*}& 0& 0\\ 0& 0& s_3& -s_4^{*}\\ 0& 0& s_4& s_3^{*}\end{array}\right).$

Above-mentioned visible, when adopting BPSK modulation, each input four information bits, then input eight information bits, two, Ji Mei road information bit when adopting QPSK modulation at every turn.

Still be modulated to example with BPSK below, the Alamouti differential space-time coding process in code method during above-mentioned two kinds of difference empty is described in detail.

Initialize installation $s_1=1/\sqrt{2},s_2=1/\sqrt{2}.$

During t=1 wherein A and B is determined by input information bits, when input bit is a ₁and a ₂time can calculate corresponding A and B, obtain s ₃and s ₄.According to input information bits a ₃and a ₄obtain new A and B, thus can basis calculate s ₅and s ₆.Parameter A, B can be calculated by following formula

$\begin{array}{c}A=\mathrm{Map}\left(a_3\right)\frac{1}{\sqrt{2}}+\mathrm{Map}\left(a_4\right)\frac{1}{\sqrt{2}}\\ B=-\mathrm{Map}\left(a_3\right)\frac{1}{\sqrt{2}}+\mathrm{Map}\left(a_4\right)\frac{1}{\sqrt{2}}\end{array},$ Wherein Map () represents the mapping of bit to symbol.

If a upper time-ofday signals current input bit is (1 0), and bit (1 0) is mapped as symbol (-1 1), obtains A=0, B=1.So $\left(\begin{array}{cc}{s}_{2t+1}& s_{2t+2}\end{array}\right)=0\·\left(\begin{array}{cc}\frac{1}{\sqrt{2}}& -\frac{1}{\sqrt{2}}\end{array}\right)+1\·\left(\begin{array}{cc}\frac{1}{\sqrt{2}}& \frac{1}{\sqrt{2}}\end{array}\right)=\left(\begin{array}{cc}\frac{1}{\sqrt{2}}& \frac{1}{\sqrt{2}}\end{array}\right).$

Correspondingly, receiver, receiving after from the first difference empty time-code of employing of transmitter or the signal of the second difference empty time-code coding, adopts corresponding coding/decoding method to carry out frequency domain differential decoding between the Received signal strength of two continuous frames.For high-visible, below for the situation of BPSK modulation, 4 transmit antennas and 1 reception antenna, respectively the homographic solution code method of above-mentioned two kinds of coding methods is described in detail.

The coding/decoding method of the first difference empty time-code comprises:

Suppose that channel matrix is H=(h ₁₁h ₁₂h ₁₃h ₁₄), transmit matrix $C=\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ d_{31}& d_{32}\\ d_{41}& d_{42}\end{array}\right),$ Then Received signal strength is R=HC+N, and wherein N is noise matrix.

Moment 1 Received signal strength $\left(\begin{array}{cc}{r}_1& r_2\end{array}\right)=\mathrm{HW}\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right)+N^{\′},$ Moment 2 Received signal strength $\left(\begin{array}{cc}{r}_3& r_4\end{array}\right)=\mathrm{HW}\left(\begin{array}{cc}{s}_3& -s_4^{*}\\ s_4& s_3^{*}\end{array}\right)+N^{\′\′},$

Due to code signal s ₃, s ₄with s ₁, s ₂and transmitting information bit has relation, Received signal strength r ₁, r ₂, r ₃and r ₄also inherent contact is had.R to received signal ₁, r ₂, r ₃and r ₄process, obtain variable R ₁and R ₂

$R_1=\left(\begin{array}{cc}{r}_3& r_4^{*}\end{array}\right)\·{\left(\begin{array}{cc}{r}_1& r_2^{*}\end{array}\right)}^{*}=\left(\begin{array}{cc}{s}_3& s_4\end{array}\right)\left(\begin{array}{cc}{h}_{11}^{\′}& -h_{12}^{\′*}\\ h_{12}^{\′}& h_{11}^{\′*}\end{array}\right){\left(\begin{array}{cc}{h}_{11}^{\′}& -h_{12}^{\′*}\\ h_{12}^{\′}& h_{11}^{\′*}\end{array}\right)}^{*}{\left(\begin{array}{cc}{s}_1^{*}& s_2^{*}\end{array}\right)}^T+N^{\′\′\′}=({\left|h_{11}^{\′}\right|}^2+{\left|h_{12}^{\′}\right|}^2)A+N^{\′\′\′}$

$R_2=\left(\begin{array}{cc}{r}_3& r_4^{*}\end{array}\right)\·{\left(\begin{array}{cc}{r}_2& {-r}_1^{*}\end{array}\right)}^{*}=\left(\begin{array}{cc}{s}_3& s_4\end{array}\right)\left(\begin{array}{cc}{h}_{11}^{\′}& -h_{12}^{\′*}\\ h_{12}^{\′}& h_{11}^{\′*}\end{array}\right){\left(\begin{array}{cc}{h}_{11}^{\′}& -h_{12}^{\′*}\\ h_{12}^{\′}& h_{11}^{\′*}\end{array}\right)}^{*}{\left(\begin{array}{cc}-s_2& s_1\end{array}\right)}^T+N^{\′\′\′\′}=({\left|h_{11}^{\′}\right|}^2+{\left|h_{12}^{\′}\right|}^2)B+N^{\′\′\′\′}$

R ₁and R ₂the convergent-divergent identical to a size of A with B can be considered as, so can obtain A and B maximal possibility estimation

(R ₁R ₂)＝(|h′ ₁₁| ²+|h′ ₁₂| ²)(A B)+(N″′ N″″)

$\left(\begin{array}{cc}A& B\end{array}\right)=\arg \underset{\left(\begin{array}{cc}A& B\end{array}\right)\∈V}{\max }\mathrm{Re}\{\left(\begin{array}{cc}A& B\end{array}\right)\·\left(\begin{array}{cc}{R^{*}}_1& {R^{*}}_2\end{array}\right)\}$

N ' and N in above formula " be noise signal, N " ' and N " " be noise relevant signals, V is the set of vectors that (A B) forms.Calculated (A B) by above formula.

Because vector (A B) and transmitting information bit have mapping relations one by one, therefore can be obtained launching information bit by (A B), complete decoding.

The coding/decoding method of the second difference empty time-code comprises:

Suppose that channel matrix is H=(h ₁₁h ₁₂h ₁₃h ₁₄), transmit matrix $C=\left(\begin{array}{cccc}{s}_1& -s_2^{*}& 0& 0\\ s_2& s_1^{*}& 0& 0\\ 0& 0& s_3& -s_4^{*}\\ 0& 0& s_4& s_3^{*}\end{array}\right),$ Then Received signal strength is R=HC+N, and wherein N is noise matrix.

Received signal strength can be written as again

$\left(\begin{array}{cccc}{r}_1& r_2& r_3& r_4\end{array}\right)=\left(\begin{array}{cccc}{h}_{11}& h_{12}& h_{13}& h_{14}\end{array}\right)\left(\begin{array}{cccc}{s}_1& -s_2^{*}& 0& 0\\ s_2& s_1^{*}& 0& 0\\ 0& 0& s_3& -s_4^{*}\\ 0& 0& s_4& s_3^{*}\end{array}\right)+\left(\begin{array}{c}{n}_1\\ n_2\\ n_3\\ n_4\end{array}\right)$

$\left(\begin{array}{cccc}{r}_5& r_6& r_7& r_8\end{array}\right)=\left(\begin{array}{cccc}{h}_{11}& h_{12}& h_{13}& h_{14}\end{array}\right)\left(\begin{array}{cccc}{s}_5& -s_6^{*}& 0& 0\\ s_6& s_5^{*}& 0& 0\\ 0& 0& s_7& -s_8^{*}\\ 0& 0& s_8& s_7^{*}\end{array}\right)+\left(\begin{array}{c}{n}_5\\ n_6\\ n_7\\ n_8\end{array}\right)$

Received signal strength r ₁, r ₂with the s that transmits ₁, s ₂there is relation, r ₅, r ₆with the s that transmits ₅, s ₆there is relation.Due to s in an encoding process ₅, s ₆with s ₁, s ₂, the peculiar relation of transmitting ratio of making a start, the Received signal strength r of its correspondence ₅, r ₆with r ₁, r ₂also inner link is had.

Calculate following formula

$\begin{array}{c}{R}_1=\left(\begin{array}{cc}{r}_5& r_6^{*}\end{array}\right)\·{\left(\begin{array}{cc}{r}_1& r_2^{*}\end{array}\right)}^{*}=\left(\begin{array}{cc}{s}_5& s_6\end{array}\right)\left(\begin{array}{cc}{h}_{11}& -h_{12}^{*}\\ h_{12}& h_{11}^{*}\end{array}\right){\left(\begin{array}{cc}{h}_{11}& -h_{12}^{*}\\ h_{12}& h_{11}^{*}\end{array}\right)}^{*}{\left(\begin{array}{cc}{s}_1^{*}& s_2^{*}\end{array}\right)}^T+N^{\′\′\′}\\ =({\left|h_{11}\right|}^2+{\left|h_{12}\right|}^2)A+N^{\′\′\′}\end{array}$

$\begin{array}{c}{R}_2=\left(\begin{array}{cc}{r}_5& r_6^{*}\end{array}\right)\·{\left(\begin{array}{cc}{r}_2& {-r}_1^{*}\end{array}\right)}^{*}=\left(\begin{array}{cc}{s}_5& s_6\end{array}\right)\left(\begin{array}{cc}{h}_{11}& -h_{12}^{*}\\ h_{12}& h_{11}^{*}\end{array}\right){\left(\begin{array}{cc}{h}_{11}& -h_{12}^{*}\\ h_{12}& h_{11}^{*}\end{array}\right)}^{*}{\left(\begin{array}{cc}{-s}_2& s_1\end{array}\right)}^T+N^{\′\′\′\′}\\ =({\left|h_{11}\right|}^2+{\left|h_{12}\right|}^2)B+N^{\′\′\′\′}\end{array}$

Wherein N " ' and N " " is noise relevant signals.By the known R of above formula ₁and R ₂be respectively A and B channel modulus value and convergent-divergent, and convergent-divergent multiple is identical.So maximal possibility estimation can be carried out by following formula to A and B

$\left(\begin{array}{cc}A& B\end{array}\right)=\arg \underset{\left(\begin{array}{cc}A& B\end{array}\right)\∈V}{\max }\mathrm{Re}\{\left(\begin{array}{cc}A& B\end{array}\right)\·\left(\begin{array}{cc}{R^{*}}_1& {R^{*}}_2\end{array}\right)\}$

In above formula, V is the set of vectors that (A B) forms.After obtaining (A B).Because vector (A B) and transmitting information bit have mapping relations one by one, therefore can be obtained launching information bit by (A B), thus complete decoding.

During specific implementation, in the embodiment of the present invention, also first can determine selectivity of channel frequency, when selectivity of channel frequency is strong, preferably code method during the first difference empty; When selectivity of channel frequency is weak, code method when can adopt the first difference empty, code method when also can adopt the second difference empty.Now, current selected coded system can be indicated to receiver by transmitter.

Above the method for transmitting signals in the embodiment of the present invention is described in detail, again the signal transmission system in the embodiment of the present invention has been described in detail below.

Fig. 6 is the exemplary block diagram of signal transmission system in the embodiment of the present invention.As shown in Figure 6, this system comprises: transmitter and receiver.

Wherein, transmitter is for determining the translational speed pattern that receiver is current, when described translational speed pattern is low speed Move Mode, the coded system of coherent transmission mode is adopted to encode to signal to be sent, when described Move Mode is high-speed mobile pattern, adopt the coded system of noncoherent transmission modes to encode to signal to be sent, the signal after coding is sent to receiver.

Receiver, for receiving the signal from described transmitter, utilizes the decoding process corresponding with coded system to decode to received signal.

Wherein, if the coded system of the coded system of coherent transmission mode and noncoherent transmission modes only has a kind of coded system selective respectively, the coded system that then receiver can be corresponding according to self determined current translational speed pattern determination received signal, utilizes the decoding process corresponding with coded system to decode to described Received signal strength afterwards.Or, coded system corresponding for signal after described coding or translational speed pattern can be indicated to receiver by transmitter further, the translational speed pattern of the coding correspondence indicated according to transmitter by receiver or coded system, determine the coded system that Received signal strength is corresponding, utilize the decoding process corresponding with coded system to decode to described Received signal strength afterwards.

If the coded system of coherent transmission mode has more than a kind of coded system, coded system that is selective and/or noncoherent transmission modes has more than a kind of coded system selective, then by transmitter, coded system corresponding for Signal coding can be indicated to receiver, receiver determines according to the described instruction of transmitter the coded system that received signal is corresponding, utilizes the decoding process corresponding with coded system to decode afterwards to described Received signal strength.

During specific implementation, the translational speed pattern that transmitter can be current according to the feedback information determination receiver of receiver.

Such as, receiver can detect self current translational speed further, the current translational speed detected and the threshold speed preset are compared, if determined current translational speed is higher than described threshold speed, then determine that self current translational speed pattern is high-speed mobile pattern, otherwise determine that self current translational speed pattern is low speed Move Mode, determined current translational speed pattern is indicated to transmitter.Correspondingly, transmitter, according to the instruction of receiver, determines the translational speed pattern that receiver is current.Wherein, receiver can utilize the information of 1 bit that determined current translational speed pattern is indicated to transmitter.

Or detected current translational speed, after the current translational speed detecting self, is indicated to transmitter by receiver.Correspondingly, by transmitter, the current translational speed of received receiver and the threshold speed preset are compared, if described current translational speed is higher than described threshold speed, then determine that the current translational speed pattern of receiver is high-speed mobile pattern, otherwise determine that the current translational speed pattern of receiver is low speed Move Mode.

Corresponding with the method in the present embodiment, transmitter when adopting the coded system of noncoherent transmission modes to encode to signal to be sent, code method when can adopt the difference empty shown in Fig. 2 to Fig. 5 equally.Correspondingly, receiver after determining the coded system that Received signal strength is corresponding, can carry out frequency domain differential decoding between the Received signal strength of two continuous frames.During specific implementation, first transmitter also can determine selectivity of channel frequency, when selectivity of channel frequency is strong, and preferably code method during the first difference empty; When selectivity of channel frequency is weak, code method when can adopt the first difference empty, code method when also can adopt the second difference empty.Now, current selected coded system can be indicated to receiver by transmitter.

During specific implementation, the transmitter in the embodiment of the present invention can as shown in Figure 6, specifically comprise: velocity mode determination module, the first coding module, the second coding module and signal transmitting module.

Wherein, velocity mode determination module is for determining that the current translational speed pattern of receiver is low speed Move Mode or high-speed mobile pattern.During specific implementation, the translational speed pattern that velocity mode determination module can be current according to the feedback information determination receiver of receiver.

First coding module is used for when the translational speed pattern that described velocity mode determination module is determined is low speed Move Mode, adopts the coded system of coherent transmission mode to encode to signal to be sent.

Second coding module is used for when the translational speed pattern that described velocity mode determination module is determined is high-speed mobile pattern, adopts the coded system of noncoherent transmission modes to encode to signal to be sent.

Signal transmitting module is used for the signal after by described first coding module or the second coding module coding and sends to receiver.

Wherein, velocity mode determination module directly can determine the present speed pattern of receiver according to the current translational speed pattern of receiver instruction, the current translational speed that also can indicate according to receiver, by comparing with the threshold speed preset the current translational speed pattern determining receiver.

Further, if the coded system of the coded system of coherent transmission mode and noncoherent transmission modes only has a kind of coded system selective respectively, then signal transmitting module the coded system that the signal after described coding is corresponding or translational speed pattern can be indicated to receiver.

If the coded system of coherent transmission mode has more than a kind of coded system, coded system that is selective and/or noncoherent transmission modes has more than a kind of coded system selective, then coded system corresponding for Signal coding can be indicated to receiver by signal transmitting module.

During specific implementation, described second coding module can be used for the differential space-time coding method realized shown in Fig. 2 to Fig. 5, correspondingly, shown in corresponding diagram 2 and Fig. 3 during differential space-time coding method, this second coding module can specifically comprise: the first modulation module and the first precoding module (not shown in Fig. 6).

Wherein, the first modulation module is used for carrying out Alamouti differential space-time coding to the two-way information bit of current input, obtains code signal s ₁and s ₂.First precoding module is used for the code signal s obtained described modulation module ₁and s ₂carry out Alamouti Space Time Coding, obtain space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right),$ Utilize encoder matrix W _{m × 2}, by described space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right)$ Expand to M transmit antennas, obtain the matrix that transmits $\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ ...& ...\\ d_{M1}& d_{M2}\end{array}\right),$ Wherein, W be M × M unitary matrix any two row, M be more than or equal to 2 arbitrary integer, subscript * represents complex conjugate.

Shown in corresponding diagram 4 and Fig. 5 during differential space-time coding method, this second coding module can specifically comprise: the second modulation module and the second precoding module (not shown in Fig. 6).

Wherein, second modulation module comprises N/2 the Alamouti differential space-time coding unit that corresponding N transmit antennas pre-sets, each Alamouti differential space-time coding unit carries out Alamouti differential space-time coding to the two-way information bit of input self respectively, obtains code signal s ₁, s ₂..., s _n-1, s _n; Wherein, N be more than or equal to 2 even number.Second precoding module is used for described code signal s ₁, s ₂..., s _n-1, s _ncarry out space-frequency block codes SFBC+ frequency error factor transmitting diversity FSTD Space Time Coding, obtain the matrix that transmits $\left(\begin{array}{ccccc}{s}_1& -s_2^{*}& ...& 0& 0\\ s_2& s_1^{*}& ...& 0& 0\\ ...& ...& ...& ...& ...\\ 0& 0& ...& s_{N-1}& -s_N^{*}\\ 0& 0& ...& s_N& s_{N-1}^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate.

Or this second coding module also can comprise above-mentioned first modulation module, the first precoding mould, the second modulation module, the second precoding module, and a selectivity of channel frequency determination module simultaneously.

Wherein, selectivity of channel frequency determination module is used for determining selectivity of channel frequency, when selectivity of channel frequency is strong, notifies that the first modulation module and the first precoding module are treated code signal and encoded; When selectivity of channel frequency is weak, notify that the first modulation module and the first precoding module or the second modulation module and the second precoding module are treated code signal and encoded.Now, current selected coded system can be indicated to receiver by signal transmitting module.

During specific implementation, the receiver in the embodiment of the present invention can as shown in Figure 6, specifically comprise: signal receiving module, the first decoder module and the second decoder module.

Wherein, signal receiving module is for receiving the signal from transmitter, when the coded system determining described signal is the coded system of coherent transmission mode, decode described Signal transmissions to the first decoder module, when the coded system determining described signal is the coded system of noncoherent transmission modes, decode described Signal transmissions to the second decoder module.

First decoder module is used for the signal transmitted described signal receiving module, adopts the decoding process of relevant detecting pattern to decode.

Second decoder module is used for the signal transmitted described signal receiving module, adopts the decoding process of noncoherent detection modes to decode.

Further, this receiver also can comprise: velocity measuring module, mode decision module and information indicating module.

Wherein, velocity measuring module is for detecting the current translational speed of described receiver.

The current translational speed that mode decision module is used for velocity measuring module to detect compares with the threshold speed preset, if described current translational speed is higher than described threshold speed, then determine that self current translational speed pattern is high-speed mobile pattern, otherwise determine that self current translational speed pattern is low speed Move Mode.

The current translational speed pattern that information indicating module is used for described mode decision module to determine is indicated to transmitter.

Or also can not comprise this mode decision module, then the current translational speed that information indicating module can be used for velocity measuring module detects is indicated to transmitter, by the translational speed pattern of transmitter determination receiver.

During specific implementation, signal receiving module can according to the determined current translational speed pattern of mode decision module, or according to the translational speed pattern of the coding correspondence of transmitter instruction or coded system, determines the coded system that received signal is corresponding.

In addition, corresponding with the coded system that transmitter adopts, the second decoder module also can comprise difference empty time-code decoder module further, for carrying out frequency domain differential decoding between the Received signal strength of two continuous frames.

It will be appreciated by those skilled in the art that accompanying drawing is the schematic diagram of a preferred embodiment, the module in accompanying drawing or flow process might not be that enforcement the present invention is necessary.

It will be appreciated by those skilled in the art that the module in the device in embodiment can be distributed in the device of embodiment according to embodiment description, also can carry out respective change and be arranged in the one or more devices being different from the present embodiment.The module of above-described embodiment can merge into a module, also can split into multiple submodule further.

Part steps in the embodiment of the present invention, can utilize software simulating, and corresponding software program can be stored in the storage medium that can read, as CD or hard disk etc.

The foregoing is only preferred embodiment of the present invention, be not intended to limit protection scope of the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (13)

1. a method for transmitting signals, is characterized in that, the method comprises:

The translational speed pattern that transmitter determination receiver is current;

When described translational speed pattern is low speed Move Mode, the coded system of coherent transmission mode is adopted to encode to signal to be sent, when described translational speed pattern is high-speed mobile pattern, the coded system of noncoherent transmission modes is adopted to encode to signal to be sent;

Signal after coding is sent to receiver;

The coded system of described employing noncoherent transmission modes is carried out coding to signal to be sent and is comprised:

Determine selectivity of channel frequency, when described selectivity of channel frequency is strong, when adopting the first difference empty, coding mode is treated and is sent signal and encode; When described selectivity of channel frequency is weak, when adopting the first difference empty, when coding mode or the second difference empty, coding mode is treated and is sent signal and encode;

During the first difference empty of described employing, coding mode is treated and is sent signal and carry out coding and comprise:

Input two-way information bit, carries out Alamouti differential space-time coding to described two-way information bit, obtains code signal s ₁and s ₂;

To described code signal s ₁and s ₂carry out Alamouti Space Time Coding, obtain space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate;

Utilize encoder matrix W _{m × 2}, by described space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right)$ Expand to M transmit antennas, obtain the matrix that transmits $\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ ...& ...\\ d_{M1}& d_{M2}\end{array}\right),$ Wherein, W be M × M unitary matrix any two row, M be more than or equal to 2 arbitrary integer;

During described employing the second difference empty, coding mode is treated and is sent signal and carry out coding and comprise:

Corresponding N transmit antennas pre-sets N/2 Alamouti differential space-time coding unit, N be more than or equal to 2 even number;

Corresponding each Alamouti differential space-time coding unit inputs two-way information bit respectively, and each Alamouti differential space-time coding unit carries out Alamouti differential space-time coding to the two-way information bit of input self respectively, obtains code signal s ₁, s ₂..., s _n-1, s _n;

To described code signal s ₁, s ₂..., s _n-1, s _ncarry out space-frequency block codes SFBC+ frequency error factor transmitting diversity FSTD Space Time Coding, obtain the matrix that transmits $\left(\begin{array}{ccccc}{s}_1& -s_2^{*}& ...& 0& 0\\ s_2& s_1^{*}& ...& 0& 0\\ ...& ...& ...& ...& ...\\ 0& 0& ...& s_{N-1}& -s_N^{*}\\ 0& 0& ...& s_N& s_{N-1}^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate.

2. the method for claim 1, it is characterized in that, the method comprises further: the current translational speed of receiver detection self, the current translational speed detected and the threshold speed preset are compared, if described current translational speed is higher than described threshold speed, then determine that self current translational speed pattern is high-speed mobile pattern, otherwise determine that self current translational speed pattern is low speed Move Mode, determined current translational speed pattern is indicated to transmitter;

The current translational speed pattern of described transmitter determination receiver is: transmitter, according to the instruction of described receiver, determines the translational speed pattern that receiver is current.

3. method as claimed in claim 2, is characterized in that, describedly determined current translational speed pattern is indicated to transmitter is: utilize the information of 1 bit that determined current translational speed pattern is indicated to transmitter.

4. the method for claim 1, is characterized in that, the method comprises further: the current translational speed of receiver detection self, is indicated to transmitter by detected current translational speed;

The current translational speed pattern of described transmitter determination receiver for: the current translational speed of received receiver and the threshold speed preset compare by transmitter, if described current translational speed is higher than described threshold speed, then determine that the current translational speed pattern of receiver is high-speed mobile pattern, otherwise determine that the current translational speed pattern of receiver is low speed Move Mode.

5. the method for claim 1, it is characterized in that, the method comprises further: receiver receives the described signal from transmitter, according to self determined current translational speed pattern, or according to the translational speed pattern of coding correspondence of transmitter instruction, determine the coded system that Received signal strength is corresponding, utilize the decoding process corresponding with coded system to decode to described Received signal strength.

6. the method for claim 1, is characterized in that, the method comprises further:

Coded system corresponding for signal after described coding is indicated to receiver by transmitter;

Receiver receives the described signal from transmitter, and the coded system according to transmitter instruction determines the coded system that described signal is corresponding, utilizes the decoding process corresponding with coded system to decode to described signal.

7. a signal transmission system, is characterized in that, this system comprises: transmitter and receiver;

Described transmitter is for determining the translational speed pattern that receiver is current, when described translational speed pattern is low speed Move Mode, the coded system of coherent transmission mode is adopted to encode to signal to be sent, when described translational speed pattern is high-speed mobile pattern, adopt the coded system of noncoherent transmission modes to encode to signal to be sent, the signal after coding is sent to described receiver;

Described receiver, for receiving the signal from described transmitter, utilizes the decoding process corresponding with coded system to decode to received signal;

The coded system of described employing noncoherent transmission modes is carried out coding to signal to be sent and is comprised:

Determine selectivity of channel frequency, when described selectivity of channel frequency is strong, when adopting the first difference empty, coding mode is treated and is sent signal and encode; When described selectivity of channel frequency is weak, when adopting the first difference empty, when coding mode or the second difference empty, coding mode is treated and is sent signal and encode;

During the first difference empty of described employing, coding mode is treated and is sent signal and carry out coding and comprise:

Input two-way information bit, carries out Alamouti differential space-time coding to described two-way information bit, obtains code signal s ₁and s ₂;

To described code signal s ₁and s ₂carry out Alamouti Space Time Coding, obtain space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate;

Utilize encoder matrix W _{m × 2}, by described space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right)$ Expand to M transmit antennas, obtain the matrix that transmits $\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ ...& ...\\ d_{M1}& d_{M2}\end{array}\right),$ Wherein, W be M × M unitary matrix any two row, M be more than or equal to 2 arbitrary integer;

During described employing the second difference empty, coding mode is treated and is sent signal and carry out coding and comprise:

Corresponding N transmit antennas pre-sets N/2 Alamouti differential space-time coding unit, N be more than or equal to 2 even number;

Corresponding each Alamouti differential space-time coding unit inputs two-way information bit respectively, and each Alamouti differential space-time coding unit carries out Alamouti differential space-time coding to the two-way information bit of input self respectively, obtains code signal s ₁, s ₂..., s _n-1, s _n;

To described code signal s ₁, s ₂..., s _n-1, s _ncarry out space-frequency block codes SFBC+ frequency error factor transmitting diversity FSTD Space Time Coding, obtain the matrix that transmits $\left(\begin{array}{ccccc}{s}_1& -s_2^{*}& ...& 0& 0\\ s_2& s_1^{*}& ...& 0& 0\\ ...& ...& ...& ...& ...\\ 0& 0& ...& s_{N-1}& -s_N^{*}\\ 0& 0& ...& s_N& s_{N-1}^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate.

8. system as claimed in claim 7, it is characterized in that, described receiver is further used for the current translational speed detecting self, the current translational speed detected and the threshold speed preset are compared, if described current translational speed is higher than described threshold speed, then determine that self current translational speed pattern is high-speed mobile pattern, otherwise determine that self current translational speed pattern is low speed Move Mode, determined current translational speed pattern is indicated to described transmitter;

Described transmitter, according to the instruction of described receiver, determines the translational speed pattern that described receiver is current.

9. a transmitter, is characterized in that, this transmitter comprises:

Velocity mode determination module, for determining that the current translational speed pattern of receiver is low speed Move Mode or high-speed mobile pattern;

First coding module, when the translational speed pattern for determining at described velocity mode determination module is low speed Move Mode, adopts the coded system of coherent transmission mode to encode to signal to be sent;

Second coding module, when the translational speed pattern for determining at described velocity mode determination module is high-speed mobile pattern, adopts the coded system of noncoherent transmission modes to encode to signal to be sent;

Signal transmitting module, for sending to receiver by the signal after described first coding module or the second coding module coding;

Described second coding module comprises: selectivity of channel frequency determination module, the first modulation module, the first precoding module, the second modulation module and the second precoding module;

Described selectivity of channel frequency determination module is used for determining selectivity of channel frequency, when selectivity of channel frequency is strong, notifies that the first modulation module and the first precoding module are treated code signal and encoded; When selectivity of channel frequency is weak, notify that the first modulation module and the first precoding module or the second modulation module and the second precoding module are treated code signal and encoded;

First modulation module, for carrying out Alamouti differential space-time coding to the two-way information bit of current input, obtains code signal s ₁and s ₂;

First precoding module, for the code signal s obtained described first modulation module ₁and s ₂carry out Alamouti Space Time Coding, obtain space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right),$ Utilize encoder matrix W _{m × 2}, by described space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right)$ Expand to M transmit antennas, obtain the matrix that transmits $\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ ...& ...\\ d_{M1}& d_{M2}\end{array}\right),$ Wherein, W be M × M unitary matrix any two row, M be more than or equal to 2 arbitrary integer, subscript * represents complex conjugate;

Second modulation module, comprise N/2 the Alamouti differential space-time coding unit that corresponding N transmit antennas pre-sets, each Alamouti differential space-time coding unit carries out Alamouti differential space-time coding to the two-way information bit of input self respectively, obtains code signal s ₁, s ₂..., s _n-1, s _n; Wherein, N be more than or equal to 2 even number;

Second precoding module, for described code signal s ₁, s ₂..., s _n-1, s _ncarry out space-frequency block codes SFBC+ frequency error factor transmitting diversity FSTD Space Time Coding, obtain the matrix that transmits $\left(\begin{array}{ccccc}{s}_1& -s_2^{*}& ...& 0& 0\\ s_2& s_1^{*}& ...& 0& 0\\ ...& ...& ...& ...& ...\\ 0& 0& ...& s_{N-1}& -s_N^{*}\\ 0& 0& ...& s_N& s_{N-1}^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate;

The coded system that described signal transmitting module is further used for the signal after by described coding corresponding is indicated to receiver.

10. transmitter as claimed in claim 9, it is characterized in that, coded system corresponding for the signal after described coding or translational speed pattern are indicated to receiver by described signal transmitting module further.

11. 1 kinds of receivers, is characterized in that, this receiver comprises:

Signal receiving module, for receiving the signal from transmitter, when the coded system determining described signal is the coded system of coherent transmission mode, the first decoder module is given by described Signal transmissions, when the coded system determining described signal is the coded system of noncoherent transmission modes, give the second decoder module by described Signal transmissions;

First decoder module, for the signal transmitted described signal receiving module, adopts the decoding process of relevant detecting pattern to decode;

Second decoder module, for the signal transmitted described signal receiving module, adopts the decoding process of noncoherent detection modes to decode;

The coded system of described employing noncoherent transmission modes is: when determining that selectivity of channel frequency is strong, coding mode when adopting the first difference empty; When determining that selectivity of channel frequency is weak, coding mode when coding mode or the second difference empty when adopting the first difference empty;

During the first difference empty described, coding mode comprises:

Input two-way information bit, carries out Alamouti differential space-time coding to described two-way information bit, obtains code signal s ₁and s ₂;

To described code signal s ₁and s ₂carry out Alamouti Space Time Coding, obtain space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate;

Utilize encoder matrix W _{m × 2}, by described space-time code matrix $\left(\begin{array}{cc}{s}_1& -s_2^{*}\\ s_2& s_1^{*}\end{array}\right)$ Expand to M transmit antennas, obtain the matrix that transmits $\left(\begin{array}{cc}{d}_{11}& d_{12}\\ d_{21}& d_{22}\\ ...& ...\\ d_{M1}& d_{M2}\end{array}\right),$ Wherein, W be M × M unitary matrix any two row, M be more than or equal to 2 arbitrary integer;

During described the second difference empty, coding mode comprises:

Corresponding N transmit antennas pre-sets N/2 Alamouti differential space-time coding unit, N be more than or equal to 2 even number;

Corresponding each Alamouti differential space-time coding unit inputs two-way information bit respectively, and each Alamouti differential space-time coding unit carries out Alamouti differential space-time coding to the two-way information bit of input self respectively, obtains code signal s ₁, s ₂..., s _n-1, s _n;

To described code signal s ₁, s ₂..., s _n-1, s _ncarry out space-frequency block codes SFBC+ frequency error factor transmitting diversity FSTD Space Time Coding, obtain the matrix that transmits $\left(\begin{array}{ccccc}{s}_1& -s_2^{*}& ...& 0& 0\\ s_2& s_1^{*}& ...& 0& 0\\ ...& ...& ...& ...& ...\\ 0& 0& ...& s_{N-1}& -s_N^{*}\\ 0& 0& ...& s_N& s_{N-1}^{*}\end{array}\right),$ Wherein, subscript * represents complex conjugate.

12. receivers as claimed in claim 11, it is characterized in that, this receiver comprises further:

Velocity measuring module, for detecting the current translational speed of described receiver;

Mode decision module, current translational speed for described velocity measuring module being detected compares with the threshold speed preset, if described current translational speed is higher than described threshold speed, then determine that self current translational speed pattern is high-speed mobile pattern, otherwise determine that self current translational speed pattern is low speed Move Mode;

Information indicating module, is indicated to transmitter for the current translational speed pattern determined by described mode decision module.

13. receivers as described in claim 11 or 12, it is characterized in that, described second decoder module comprises: difference empty time-code decoder module, for carrying out frequency domain differential decoding between the Received signal strength of two continuous frames.