CN106230490A - A kind of phase place in order rotates Precoding Design method - Google Patents

Abstract

The present invention relates to a kind of phase place in order and rotate Precoding Design method, consider channel gain to the impact of Euclidean distance between the constellation point of space, the method utilizes the phase information of each channel to carry out the Precoding Design rotated based on phase place, be different from conventional phase rotation precoding arranges postrotational phase place according to antenna serial number order, the postrotational phase place of the present invention is based on channel gain sequencing information and is adjusted, and carries out the design of space planisphere for principle maximizing the Euclidean distance between the space constellation point that amplitude is close.This invention reduces the average symbol probability by mistake of system with relatively low design complexities, has reached the purpose of further lifting systematic function.

Description

A kind of phase place in order rotates Precoding Design method

Technical field

The present invention relates to a kind of phase place in order and rotate Precoding Design method, particularly relate to a kind of for sky shifting keying modulation Orderly phase place in multi-aerial transmission system rotates Precoding Design method, belongs to art communication systems field

Background technology

The empty keying (Space Shift Keying, SSK) that moves is modulated by selecting antenna activation to transmit information, is a kind of Novel multiple antennas modulation technique.Because it only activates a transmission antenna at each working time slot, it only needs one to send radio frequency Link can meet communication requirement, can efficiently solve common-channel interference, day line locking etc. of making a start in tradition multi-antenna transmission Problem, and the complexity of receiver detection algorithm can be effectively reduced.

In the multi-aerial transmission system moving keying modulation based on sky, system average erratum probability performance is by space constellation Between point (wireless channel), Euclidean distance determines, the Euclidean distance increased between the constellation point of space can be effectively reduced system Average symbol probability by mistake.In having studied, there are two kinds of methods and can increase the Euclidean distance between the constellation point of space: first, Utilize the method that power distributes to adjust the amplitude of space constellation point；Correlation technique sees document [1] and document [2], document [1]: M.Di Renzo, H.Haas " Improving the performance of space shift keying (SSK) modulationvia opportunistic power allocation,”IEEE Commun.Lett.,vol.14,no.6, Pp.500-502,2010. document [2]: M.Maleki, H.-R.Bahrami, S.Beygi, M.Kafashan, and N.H.Tran,“Space modulation with CSI:Constellation design and performanceevaluation,”IEEE Trans.Veh.Technol.,vol.62,no.4,pp.1623-1634, 2013.).Second, utilize phase place to rotate precoding to adjust the phase place of space constellation point；Correlation technique sees document [2] and literary composition Offer [3], document [3]: K.Ntontin, M.Di Renzo, A.Perez-Neira, and C.Verikoukis, “Adaptivegeneralized space shift keying(GSSK)modulation for MISO channels: Anew method for high diversity and coding gains,”in Proc.IEEE VTC fall, Yokohama,Japan,2012,pp.1-5.Wherein, utilize phase place rotation precoding to adjust the phase place of space constellation point, only need Configure corresponding phase rotation device at transmission antenna end, adjust phase rotation angle according to channel phase information in real time and make space star The phase place of seat figure each point is all assigned between [0,2 π], it is not necessary to configure extra power amplifier, because its design complexities is low and property Can improve and substantially receive significant attention.But existing phase place rotates Precoding Design method to be only focused in phase difference space constellation The impact of Euclidean distance between point, ignores amplitude difference to the impact of Euclidean distance between the constellation point of space.

Summary of the invention

For the deficiencies in the prior art, the invention provides a kind of in sky shifting keying modulation multi-aerial transmission system Phase place rotates Precoding Design method in order；

The present invention is directed to move based on sky the multi-aerial transmission system of keying modulation, make full use of channel phase information and channel Gain sequencing information, utilizes the channel gain sequencing information to maximize the Euclidean distance between the close space constellation point of amplitude to be Principle carries out the design of space planisphere, and the present invention effectively reduces the average error sign ratio of system with relatively low complexity, enters One step improves the performance of system.

The present invention summarizes:

The present invention considers to move the multi-aerial transmission system of keying modulation based on sky, and this system is by N_tRoot launches antenna, N_r Root reception antenna forms, N_t=2ⁿ, n is that first positive integer information bit data stream be grouped, and every n-bit information divides Become one group, after sky moves keying modulation, be mapped on corresponding transmission antenna, prelist carrying out the rotation of orderly phase place Be transmitted through respective channel after Ma, receiving terminal by detection channel impulse response determine transmission antenna sequence number and then Demodulation obtains information bit.The present invention utilizes channel gain sequencing information and channel phase information design rotation pre-coderThe phase place of the constellation point of amplitude sequences different in the planisphere of space is adjusted to [0,2 π] Phase place is fixing divides equally position, reaches the purpose of the average error sign ratio performance of lifting system.

The technical scheme is that

A kind of orderly phase place in sky shifting keying modulation multi-aerial transmission system rotates Precoding Design method；Described Multi-aerial transmission system includes N_tRoot launches antenna, N_rRoot reception antenna, N_t=2ⁿ, n is that positive integer concrete steps include:

(1) to N_rRoot reception antenna is numbered, and number consecutively is 1,2 ..., l ..., N_r, to N_tRoot is launched antenna and is carried out Numbering, number consecutively is 1,2 ..., i ..., N_t, the reception antenna of numbered l and N_tRoot is launched the channel vector of antenna and is denoted ash_{L, i}Antenna is launched to the channel fading system of the reception antenna of numbered l for numbered i Number, by h_{L, i}It is expressed as the form of channel gain and channel phase, i.e. Refer to phase place, specifically compile Number be i launch antenna to the channel phase information between the reception antenna of numbered l；

(2) to h_lBy channel gain information i.e. channel h_{L, i}Modulus value | | h_{L, i}| | descending descending, numbering depends on Secondary is 1,2 ..., i ..., N_t, obtain any h_{L, i}Gain sequence i^⊥；

(3) according to h_lIn any h_{L, i}Gain sequence, calculate gain sequencing numbers be i launch phase corresponding to antenna Position rotates precoding ω_{L, i}, as shown in formula I:

In formula I,It is fixed phase, order (i^⊥) be space planisphere phase sequence vector order i-th^⊥ The value of individual element；

According to h_l, the phase place that all transmitting antennas are corresponding rotates pre-coding matrix and is expressed as diagonal matrix w_l,

(4) for numbered 1,2 ..., l ..., N_rN_rRoot reception antenna, repeats step (2) and (3), obtains all standby Phase selection position rotates pre-coding matrix set, and alternative phase place rotates in pre-coding matrix set and has N_rIndividual precoder；Due to often One reception antenna and N_tRoot launches antenna can constitute a multi-antenna transmission single antenna reception system, can be such System one precoder of design, a total of N of receiving terminal_rRoot reception antenna, so alternative phase place rotates pre-coding matrix set In have N_rIndividual precoder.

(5) with minimize average symbol probability by mistake the performance upper bound as criterion, at all N_rIndividual precoder selects Excellent precoder w is as the precoder of last design, as shown in formula II:

$W=\arg {\min }_{W_l,l=1,2,\mathrm{...},N_r}{\stackrel{\‾}{P}}_s(H,W_l)---\left(II\right)$

In formula II,It is channel matrix,Performance for average symbol probability by mistake The upper bound,Expression formula as shown in formula III:

${\stackrel{\‾}{P}}_s(H,W_l)=\frac{1}{N_t}{\mathrm{\Σ}}_{i=1}^{N_t}{\mathrm{\Σ}}_{k=1,k\≠i}^{N_t}Q\left(\frac{\left|\right|{\mathrm{HW}}_l(e_i-e_k)\left|\right|}{\sqrt{2}\mathrm{\σ}}\right)---\left(III\right)$

In formula III, Q is Gauss Q function, e_iAnd e_kBeing respectively i-th and kth base vector, σ is the standard of Gaussian noise Difference.

According to currently preferred, the phase sequence vector order of space planisphere is 1 to N_tOne group of number of permutations constitute Vector, concrete generation step is:

A, calculating n=log₂(N_t) determine the frequency n needing to carry out variable update；

B, initialization order=[1], initialize more new variables m=1；

If the calculating of c m ＞ n explanation phase sequence vector completes, otherwise, carry out step d；

D, generation one 1 × 2^m-1All 1's matrix, be designated asIf intermediate variable matrix Utilize intermediate variable matrix update order, update operation for order=reshape (X, 1,2^m), reshape (X, 1,2^m) represent Matrix x is rearranged for one 1 × 2 according to row order^mMatrix, m is added 1 simultaneously, return step c.

The invention has the beneficial effects as follows:

Compared with rotating Precoding Design with the existing empty phase place moved in keyed system, the present invention has taken into full account channel gain On the impact of Euclidean distance between the constellation point of space, it is based on phase place rotation pre-that the method utilizes the phase information of each channel to carry out Code Design, be different from conventional phase rotation precoding arranges postrotational phase place according to antenna serial number order, and the present invention is revolved Phase place after Zhuaning is based on channel gain sequencing information and is adjusted, Europe space constellation point between close to maximize amplitude Family name's distance carries out the design of space planisphere for principle.This invention reduces the average erratum of system with relatively low design complexities Number probability, has reached the purpose of further lifting systematic function.

Accompanying drawing explanation

Fig. 1 is the system model figure of the multi-aerial transmission system moving keying modulation in the present invention based on sky；

Fig. 2 is the flow chart of orderly phase place rotation pre-coder method for designing in the present invention.

Fig. 3 is the flow chart of the phase sequence vector order generating space planisphere in the present invention.

Fig. 4 is N in the present invention_r=1 andAfter the orderly phase place of Shi Caiyong rotates precoding The explanation schematic diagram of space planisphere.

Detailed description of the invention

Below in conjunction with Figure of description and embodiment, the present invention is further qualified, but is not limited to this.

Embodiment

A kind of orderly phase place in sky shifting keying modulation multi-aerial transmission system rotates Precoding Design method, such as figure Shown in 2, described multi-aerial transmission system includes N_t=16 transmitting antennas, N_r=2 reception antennas, multi-aerial transmission system System model figure is as it is shown in figure 1, concrete steps include:

(1) being numbered 2 reception antennas, numbered 1,2, be numbered 16 transmitting antennas, number consecutively is 1,2 ..., i ..., 16, the channel vector of the reception antenna of numbered l and 16 transmitting antennas is denoted ash_{L, i}The channel fading system launching the antenna reception antenna to numbered 1 for numbered i Number, by h_{L, i}It is expressed as the form of channel gain and channel phase, i.e. Refer to phase place, specifically compile It number it is the channel phase information launching the antenna reception antenna to numbered 1 of i；

(2) to h_lBy channel gain information i.e. channel h_{L, i}Modulus value | | h_{L, i}| | descending descending, numbering depends on Secondary is 1,2 ..., i ..., N_t, obtain any h_{L, i}Gain sequence i^⊥；

(3) according to h_lIn any h_{L, i}Gain sequence, calculate gain sequencing numbers be i launch phase corresponding to antenna Position rotates precoding ω_{L, i}, as shown in formula I:

In formula I,It is fixed phase, order (i^⊥) be space planisphere phase sequence vector order i-th^⊥ The value of individual element；

According to h_l, the phase place that all transmitting antennas are corresponding rotates pre-coding matrix and is expressed as diagonal matrix w_l,

(4) for numbered 1,2 ..., l ..., N_rN_rRoot reception antenna, repeats step (2) and (3), obtains all standby Phase selection position rotates pre-coding matrix set, and alternative phase place rotates in pre-coding matrix set and has N_rIndividual precoder；Due to often One reception antenna and N_tRoot launches antenna can constitute a multi-antenna transmission single antenna reception system, can be such System one precoder of design, a total of N of receiving terminal_rRoot reception antenna, so alternative phase place rotates pre-coding matrix set In have N_rIndividual precoder.

(5) with minimize average symbol probability by mistake the performance upper bound as criterion, at all N_rIndividual precoder selects Excellent precoder w is as the precoder of last design, as shown in formula II:

$W=\arg {\min }_{W_l,l=1,2,\mathrm{...},N_r}{\stackrel{\‾}{P}}_s(H,W_l)---\left(II\right)$

In formula II,It is channel matrix,Performance for average symbol probability by mistake The upper bound,Expression formula as shown in formula III:

${\stackrel{\‾}{P}}_s(H,W_l)=\frac{1}{N_t}{\mathrm{\Σ}}_{i=1}^{N_t}{\mathrm{\Σ}}_{k=1,k\≠i}^{N_t}Q\left(\frac{\left|\right|{\mathrm{HW}}_l(e_i-e_k)\left|\right|}{\sqrt{2}\mathrm{\σ}}\right)---\left(III\right)$

In formula III, Q is Gauss Q function, e_iAnd e_kBeing respectively i-th and kth base vector, σ is the standard of Gaussian noise Difference.

The phase sequence vector order of space planisphere is the vector of one group of number of permutations composition of 1 to 16, specifically generates step Suddenly it is:

By N_t=16 need to carry out four times updating operating according to calculating n=4, first, order=[1], m=1, order =[1], m=1, carry out the calculating of intermediate variableObtain the orde=[1 2] updated；Then, m=2, carry out second The calculating of secondary intermediate variableObtain the order=[1 32 4] that second time updates；Then m=3, carries out third time The calculating of intermediate variableObtain the last m=4 of order=[1 537264 8] that third time updates, enter The calculating of the 4th intermediate variable of rowObtain the order=[1 95 13 updated the 4th time 3 11 7 15 2 10 6 14 4 12 8 16]. carry out four times and updated, illustrated that calculating is complete, i.e. [1 95 13 3 11 7 15 2 10 6 14 4 12 8 16] it is antenna number N_tThe phase sequence vector of=16.The present embodiment generates space The flow process of the phase sequence vector order of planisphere is as it is shown on figure 3, use the sky after orderly phase place precoding in the present embodiment Between planisphere explanation schematic diagram as shown in Figure 4.

Claims (2)

1. the orderly phase place in sky shifting keying modulation multi-aerial transmission system rotates Precoding Design method；Described many Aerial transmission system includes N_tRoot launches antenna, N_rRoot reception antenna, N_t=2ⁿ, n is that positive integer is characterized in that, concrete steps Including:

(1) to N_rRoot reception antenna is numbered, and number consecutively is 1,2 ..., l ..., N_r, to N_tRoot is launched antenna and is numbered, Number consecutively is 1,2 ..., i ..., N_t, the reception antenna of numbered l and N_tRoot is launched the channel vector of antenna and is denoted ash_{L, i}Antenna is launched to the channel fading system of the reception antenna of numbered l for numbered i Number, by h_{L, i}It is expressed as the form of channel gain and channel phase, i.e. Refer to phase place, specifically compile Number be i launch antenna to the channel phase information between the reception antenna of numbered l；

(2) to h_lBy channel gain information i.e. channel h_{L, i}Modulus value | | h_{L, i}| | descending descending, numbering is followed successively by 1, 2 ..., i ..., N_t, obtain any h_{L, i}Gain sequence i^⊥；

(3) according to h_lIn any h_{L, i}Gain sequence, calculate phase place corresponding to antenna of launching that gain sequencing numbers is i and rotate Precoding ω_{L, i}, as shown in formula I:

In formula I,It is fixed phase, order (i^⊥) be space planisphere phase sequence vector order i-th^⊥Individual unit The value of element；

According to h_l, the phase place that all transmitting antennas are corresponding rotates pre-coding matrix and is expressed as diagonal matrix W_l,

(4) for numbered 1,2 ..., 1 ..., N_rN_rRoot reception antenna, repeats step (2) and (3), obtains all alternative phases Position rotates pre-coding matrix set, and alternative phase place rotates in pre-coding matrix set N_rIndividual precoder；

(5) with minimize average symbol probability by mistake the performance upper bound as criterion, at all N_rIndividual precoder selects the pre-of optimum Encoder W is as the precoder of last design, as shown in formula II:

$W=\arg {\min }_{W_l,l=1,2,\mathrm{...},N_r}{\stackrel{\‾}{P}}_s(H,W_l)---\left(II\right)$

In formula II,It is channel matrix,In performance for average symbol probability by mistake Boundary,Expression formula as shown in formula III:

${\stackrel{\‾}{P}}_s(H,W_l)=\frac{1}{N_t}{\Σ}_{i=1}^{N_t}{\Σ}_{k=1,k\≠i}^{N_t}Q\left(\frac{\left|\right|{\mathrm{HW}}_l(e_i-e_k)\left|\right|}{\sqrt{2}\mathrm{\σ}}\right)---\left(III\right)$

In formula III, Q is Gauss Q function, e_iAnd e_kBeing respectively i-th and kth base vector, σ is the standard deviation of Gaussian noise.

A kind of orderly phase place in sky shifting keying modulation multi-aerial transmission system the most according to claim 1 rotates pre- Code Design method, it is characterised in that the phase sequence vector order of space planisphere is 1 to N_tOne group of number of permutations constitute Vector, concrete generation step is:

A, calculating n=log₂(N_t), determine the frequency n needing to carry out variable update；

B, initialization order=[1], initialize more new variables m=1；

If c is m ＞ n, illustrates that the calculating of phase sequence vector completes, otherwise, carry out step d；

D, generation one 1 × 2^m-1All 1's matrix, be designated asIf intermediate variable matrix Utilize intermediate variable matrix update order, update operation for order=reshape (X, 1,2^m), reshape (X, 1,2^m) represent Matrix x is rearranged for one 1 × 2 according to row order^mMatrix, m is added 1 simultaneously, return step c.