CN106385324A - Radar signal detection method and apparatus thereof - Google Patents

Abstract

An embodiment of the invention discloses a radar signal detection method. The method comprises the following steps of according to a detection period, detecting whether a radar signal exists in a reference channel in a circulation mode, wherein the detection period includes detection time and idle time and the radar signal includes a plurality of radar pulses; when the radar signal exists in the reference channel, acquiring a radar period of the radar signal, wherein the radar period is a time interval between the two adjacent radar pulses; and according to the radar period, determining a type of the radar signal. Simultaneously, the embodiment of the invention also discloses a radar signal detection apparatus.

Description

A kind of Radar Signal Detection method and apparatus

Technical field

The present invention relates to the signal detection technique of the communications field, more particularly, to a kind of Radar Signal Detection method and Device.

Background technology

With the extensive application of 4G business, Long Term Evolution (Long Term Evolution, LTE) has become For currently used communication technology the most extensive and advanced, but have due to being available for the frequency spectrum resource of LTE use Limit, so that the use of LTE technology creates bottleneck.So that LTE breaks the bottleneck of frequency spectrum use, Authorize auxiliary to access (Licensed Assisted Access, LAA) technology to arise at the historic moment, that is,：By LTE Spendable frequency spectrum resource expands to unauthorized frequency range.

Common, using LAA technology so that LTE use 5.0GHz about unauthorized frequency range, by In 5.0GHz about unauthorized frequency range belong to public frequency band, have other signals in a large number to adopt this part frequency Spectrum resource is transmitted, example, and in 5GHz frequency band, the frequency spectrum resource of 5.3GHz to 5.9GHz supplies Radar system is used, for example：Weather radar, military radar or spaceborne radar navigation.If LTE with Radar system shares the frequency spectrum resource of 5.3GHz to 5.9GHz, then can lead to presence between LTE and radar system Co-channel interference, the serious transmission performance restricting LTE, disturb the proper communication of radar system simultaneously.Therefore, So that LTE device can use 5GHz frequency band transmission signal, existing LTE terminal must possess dynamic State frequency spectrum selection mechanism, wherein, dynamic spectrum selection mechanism can pass through handover operation frequency, it is to avoid wireless Signal and radar signal interfere with each other so that LTE terminal can share frequency with radar system in transmission data Band.

Specifically, when carrying out dynamic spectrum selection, first before LTE terminal carries out signal transmission, with Machine selects any one channel, then in availability detection time (the Channel availability of this channel Check time, CAC) in, persistently monitor the signal in this channel, confirm to whether there is radar on this channel Signal, if detect there is radar signal on this channel, LTE terminal must abandon present channel, weight New selection other channels simultaneously repeat snoop procedure；If detect that radar signal, LTE are not existed on this channel Terminal can carry out signal transmission using present channel, and persistently monitors radar signal when carrying out signal transmission, If radar signal is detected, LTE terminal needs to stop the radar letter on current transmission, and this channel of labelling Number, then change another channel and detected, and proceed signal biography when being not detected by radar signal Defeated.Every channel being had radar signal labelling, all in the unoccupied phase (non-occupancy of LTE terminal Period, NOP) in must not use.

Generally, radar signal is impulse form, and is transmitted with impulse cluster, each radar pulse cluster Including multiple radar pulses, the time being separated by between adjacent radar pulse cluster is longer, if this channel is current just Carrying out Radar Signal Transmission, then LTE terminal can not carry out signal transmission on this channel, but due to phase The time being separated by between adjacent radar pulse cluster is longer, and LTE terminal can carry out signal using this time in fact Transmission.But because prior art is only capable of detecting with the presence or absence of radar signal, when thunder is detected on this channel When reaching signal, LTE terminal just selects to reselect channel, or stops transmitting and changing other channels, such as Really now the radar pulse cluster of radar signal is less, and radar signal may be ended quickly, and work as radar signal and cut When only, LTE terminal may have not been completed the reselecting or to the switching of other channels so that signal of channel The Transmission time is relatively long, have impact on the transmission speed of signal, and Consumer's Experience is not high.Meanwhile, only by Currently carry out the transmission of radar signal in this channel, just abandon this channel, reselect other channels Carry out signal transmission, do not account for the communication resource between adjacent radar pulse cluster so that the communication of this channel Resource utilization is not high, causes the waste of the communication resource.

Content of the invention

For solving above-mentioned technical problem, embodiment of the present invention expectation provides a kind of Radar Signal Detection method and dress Put, it is possible to increase signaling rate, improve Consumer's Experience, save the communication resource simultaneously.

The technical scheme is that and be achieved in that：

On the one hand, the embodiment of the present invention provides a kind of Radar Signal Detection method, and methods described includes：

By whether there is radar signal on detection cycle cycle detection reference channel, described detection cycle includes examining Survey time and free time, described radar signal includes multiple radar pulses；

When there is radar signal on described reference channel, obtain the radar period of described radar signal, described Radar period is the time interval between two neighboring radar pulse；

Determine the type of described radar signal according to described radar period.

Optionally, described when there is radar signal on described reference channel, obtain described radar signal thunder The cycle of reaching includes：

When there is radar signal on described reference channel, record the adjacent radar of each two in described radar signal Time interval between pulse；

Obtain minimum time interval in the time interval between the adjacent radar pulse of described each two as described Radar period.

Optionally, the described cycle detection reference channel by detection cycle includes with the presence or absence of radar signal：

Obtain the signal on described reference channel in the detection time with reference to detection cycle, described all with reference to detection Phase is any one detection cycle；

The power spectrum of the signal on described reference channel in the described detection time with reference to detection cycle of acquisition is flat Degree；

When described power spectrum flatness is more than reference threshold, described reference channel is described with reference to detection cycle Detection time in radar pulse is detected；

When described power spectrum flatness is less than reference threshold, described reference channel is described with reference to detection cycle Detection time in be not detected by radar pulse.

Optionally, when minimum in the described time interval obtaining between the adjacent radar pulse of described each two Between be spaced as described radar period after, methods described also includes：

Judge to detect duration whether more than or equal to reference to duration, during described detection a length of by detection cycle circulation Detect the time of described reference channel；

Described included according to the type that described radar period determines described radar signal：

When described detection duration is more than or equal to described reference duration, according to described radar period determines The type of radar signal.

Optionally, after the described cycle detection reference channel by detection cycle whether there is radar signal, Methods described also includes：

When there is not radar signal on described reference channel, judge to detect whether duration is more than or equal to reference Duration, the time of reference channel described in a length of cycle detection as detection cycle during described detection；

When described detection duration is more than or equal to described reference duration, judge described reference channel in described inspection Survey in duration and whether be completely absent described radar signal；

When whether being completely absent described radar signal in described detection duration, entered by described reference channel Row signal transmission.

Optionally, described detection cycle T=τ+t, τ are detection time, and t is free time, described detection week Phase, T met formula：T≤τ+ω-2ω₀；

Wherein, ω is radar pulse width, ω₀For enable detection time τ that radar pulse is detected with The minimum that ω overlaps；

Or, described detection cycle T meets formula：

$\left\{\begin{array}{c}T\&le;\frac{pN-p}{LN-L+1}\\ max\&lsqb;{\mathrm{\&omega;}}_0,2(p-LT)+2{\mathrm{\&omega;}}_0-\mathrm{\&omega;}\&rsqb;<\mathrm{\&tau;}<T-\mathrm{\&omega;}+2{\mathrm{\&omega;}}_0\end{array}\right.;$

Wherein, ω is radar pulse width；ω₀For enable detection time τ that radar pulse is detected with The minimum that ω overlaps；L is integer, represents and wraps between n-th radar pulse and (n+1)th radar pulse Include L detection cycle；N represents the number of radar pulse in the radar pulse cluster of described radar signal；P table Show the time interval between two adjacent radar pulses.

On the other hand, the embodiment of the present invention provides a kind of Radar Signal Detection device, and described device includes：

Detector unit, for by radar signal be whether there is on detection cycle cycle detection reference channel, described Detection cycle includes detection time and free time, and described radar signal includes multiple radar pulses；

Acquiring unit, for when there is radar signal on described reference channel, obtaining described radar signal Radar period, described radar period is the time interval between two neighboring radar pulse；

Determining unit, for determining the type of described radar signal according to described radar period.

Optionally, described acquiring unit specifically for：

When there is radar signal on described reference channel, record the adjacent radar of each two in described radar signal Time interval between pulse；

Obtain minimum time interval in the time interval between the adjacent radar pulse of described each two as described Radar period.

Optionally, described detector unit specifically for：

Obtain the signal on described reference channel in the detection time with reference to detection cycle, described all with reference to detection Phase is any one detection cycle described；

The power spectrum of the signal on described reference channel in the described detection time with reference to detection cycle of acquisition is flat Degree；

When described power spectrum flatness is more than reference threshold, described reference channel is described with reference to detection cycle Detection time in radar pulse is detected；

When described power spectrum flatness is less than reference threshold, described reference channel is described with reference to detection cycle Detection time in be not detected by radar pulse.

Optionally, described device also includes：

First judging unit, for judging whether to detect duration more than or equal to reference duration, during described detection The time of reference channel described in a length of cycle detection as detection cycle；

Described determining unit specifically for when described detection duration be more than or equal to described with reference to duration when, according to Described radar period determines the type of described radar signal.

Optionally, described device also includes：

Second judging unit, for when there is not radar signal on described reference channel, judging detection duration Whether more than or equal to reference to duration, reference channel described in a length of cycle detection as detection cycle during described detection Time；

3rd judging unit, for when described detection duration is more than or equal to described reference duration, judging institute State whether reference channel is completely absent described radar signal in described detection duration；

Transmission unit, for when whether being completely absent described radar signal in described detection duration, passing through Described reference channel carries out signal transmission.

Optionally, described detection cycle T=τ+t, τ are detection time, and t is free time, described detection week Phase, T met formula：T≤τ+ω-2ω₀；

Wherein, ω is radar pulse width, ω₀For enable detection time τ that radar pulse is detected with The minimum that ω overlaps；

Or, described detection cycle T meets：

$\left\{\begin{array}{c}T\&le;\frac{pN-p}{LN-L+1}\\ max\&lsqb;{\mathrm{\&omega;}}_0,2(p-LT)+2{\mathrm{\&omega;}}_0-\mathrm{\&omega;}\&rsqb;<\mathrm{\&tau;}<T-\mathrm{\&omega;}+2{\mathrm{\&omega;}}_0\end{array}\right.;$

Wherein, ω is radar pulse width；ω₀For enable detection time τ that radar pulse is detected with The minimum that ω overlaps；L is integer, represents and wraps between n-th radar pulse and (n+1)th radar pulse Include L detection cycle；N represents the number of radar pulse in the radar pulse cluster of described radar signal；P table Show the time interval between two adjacent radar pulses.

Embodiments provide a kind of Radar Signal Detection method and device, by detection cycle cycle detection Whether there is radar signal, described detection cycle includes detection time and free time, described on reference channel Radar signal includes multiple radar pulses；When there is radar signal on described reference channel, obtain described thunder Reach the radar period of signal, described radar period is the time interval between two neighboring radar pulse, then Determine the type of described radar signal according to described radar period.Compared to prior art, due to can determine The type of radar signal, therefore, when terminal detects again and there is radar signal on current reference channel, The deadline of radar signal can be expected according to the type of radar signal, if now terminal is not also in reference When carrying out signal transmission on channel, this reference channel can not be abandoned, and after being to wait for radar signal cut-off, Select to carry out signal transmission in this reference channel, so, just can improve the utilization of the communication resource of reference channel Rate；If terminal is being currently used reference channel carrying out data transmission, and wait the time of radar signal cut-off Less than channel switching time, then terminal can not carry out channel switching, thus avoiding due to signal transmission The decline of the signaling rate that the overlong time interrupted causes, improves Consumer's Experience.

Brief description

Fig. 1 is a kind of flow chart of Radar Signal Detection method provided in an embodiment of the present invention；

Fig. 2 is the flow chart of another kind Radar Signal Detection method provided in an embodiment of the present invention；

Fig. 3 is a kind of schematic diagram of detection cycle provided in an embodiment of the present invention；

Fig. 4 is a kind of structural representation of Radar Signal Detection device provided in an embodiment of the present invention；

Fig. 5 is the structural representation of another kind Radar Signal Detection device provided in an embodiment of the present invention；

Fig. 6 is the structural representation of another Radar Signal Detection device provided in an embodiment of the present invention.

Specific embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clearly Chu, it is fully described by.

The embodiment of the present invention provides a kind of Radar Signal Detection method, is applied to terminal, as shown in figure 1, should Radar Signal Detection method includes：

Step 101, by radar signal, described detection be whether there is on detection cycle cycle detection reference channel Cycle includes detection time and free time, and described radar signal includes multiple radar pulses.

Generally, if terminal needs to carry out signal transmission, need to select a channel first, then persistently supervise Listen the signal on this channel, judge currently to whether there is radar signal on this signal.But, terminal is continuing During monitor channel, except being able to detect that radar pulse in the minority time, remaining most of the time is examined Measure is all the insignificant noise without any signal, causes the waste of detection resource, leads to terminal Power consumption higher.Therefore can select with detection cycle cycle detection.Example, described detection cycle T Including detection time τ and free time t, that is,：In detection time τ, the letter of terminal monitoring channel to be accessed Number, at one's leisure between in t, terminal is in idle condition, is not listening to the signal of channel to be accessed.So, Spend detection energy to be detected only in detection time, do not detected in free time, saved detection Energy.

Step 102, when there is radar signal on described reference channel, obtain described radar signal radar In the cycle, described radar period is the time interval between two neighboring radar pulse.

Because radar signal is transmitted with radar pulse form, the radar signal that therefore terminal gets It is radar pulse one by one.Example, after there is radar signal on reference channel is detected, terminal Record two adjacent radar pulses between time interval, then by between this two adjacent radar pulses when Between be spaced as radar period.

Step 103, determine the type of described radar signal according to described radar period.

Common, the type of radar signal is different, then the cycle of radar signal also differ, therefore can lead to Cross the type that radar period determines radar signal.Specifically, can store in the terminal in advance radar period with The corresponding relation of radar type, after getting radar period, can determine thunder according to the corresponding relation prestoring Reach the type of signal.

So, because terminal can determine the type of radar signal, therefore work as when terminal detects again The cut-off of radar signal when there is radar signal on front reference channel, can be expected according to the type of radar signal Time, if now terminal does not also carry out signal transmission on reference channel, this reference letter can not be abandoned Road, and it is to wait for radar signal by afterwards, select to carry out signal transmission in this reference channel, improve ginseng Examine the utilization rate of the communication resource of channel；If terminal is being currently used reference channel and carries out data transmission simultaneously, If the time waiting radar signal cut-off is less than the time that channel switches, terminal can not carry out channel switching, Avoid the decline of signaling rate causing due to the overlong time that signal transmission is interrupted, improve user Experience.

Preferably, when there is radar signal on described reference channel, in the radar obtaining described radar signal During the cycle, the time interval between the adjacent radar pulse of each two in described radar signal can be recorded first, Then obtain minimum time interval in the time interval between the adjacent radar pulse of described each two as described Radar period.Because terminal adopts the method cycle detection reference channel of detection time+free time, therefore remember Record the time interval between the two neighboring radar pulse obtaining and be only possible to than actual radar period more greatly, can not Can be less than actual radar period, minimum time interval in multiple time intervals of record therefore can be selected to make For radar period because the time interval of minimum be radar period probability maximum.

Optionally, when whether there is radar signal on by detection cycle cycle detection reference channel, with reference Illustrate as a example detection cycle, described is any one detection cycle described with reference to detection cycle, first may be used To obtain the signal on described reference channel in the detection time with reference to detection cycle, then obtain described reference The power spectrum flatness of the signal on described reference channel in the detection time of detection cycle, judges that power spectrum is put down Relation between smooth degree and reference threshold, when described power spectrum flatness is more than reference threshold, described reference Channel detects radar pulse in the described detection time with reference to detection cycle；When described power spectrum flatness During less than reference threshold, described reference channel is not detected by the described detection time with reference to detection cycle Radar pulse, wherein reference threshold are to pre-set as the case may be in practical application, and the present invention is implemented Example does not limit to this.

It should be noted that can also adopt energy detection method in practical application, cyclostationary characteristic detects Method, or the method such as matched filtering detection method detection radar signal, embodiment of the present invention here is not done superfluous State.

Further, minimum in the described time interval obtaining between the adjacent radar pulse of described each two After time interval is as described radar period, methods described also includes：Judge to detect duration whether more than or It is equal to reference to duration, the time of reference channel described in a length of cycle detection as detection cycle during described detection；When When described detection duration is more than or equal to described reference duration, described radar letter is determined according to described radar period Number type.

Further, after the described cycle detection reference channel by detection cycle whether there is radar signal, Methods described also includes：When there is not radar signal on described reference channel, judge to detect whether duration is big In or be equal to reference to duration, the time of reference channel described in a length of cycle detection as detection cycle during described detection； When described detection duration is more than or equal to described reference duration, judge described reference channel in described detection Whether it is completely absent described radar signal in length；Detect in duration whether be completely absent described thunder when described When reaching signal, signal transmission is carried out by described reference channel.

Specifically, described detection cycle T=τ+t, wherein, τ is detection time, and t is free time, due to The radar pulse width very little of each radar pulse, if the setting of detection time τ and free time t is unreasonable, Then can cause, in multiple detection cycles T, there is no the situation that two neighboring radar pulse is simultaneously detected, The determination of impact radar type is it is therefore desirable to determine suitable detection time τ and free time t.The present invention is real Applying example provides two kinds of determination methods：

Method one, when detection cycle T meets T≤τ+ω -2 ω₀When, described detection cycle is able to detect that Two neighboring radar pulse.

Wherein, ω is radar pulse width, ω₀For enable detection time τ that radar pulse is detected with The minimum that radar pulse width ω overlaps.

Method two, when detection cycle T meets：

$\left\{\begin{array}{c}T\&le;\frac{pN-p}{LN-L+1}\\ max\&lsqb;{\mathrm{\&omega;}}_0,2(p-LT)+2{\mathrm{\&omega;}}_0-\mathrm{\&omega;}\&rsqb;<\mathrm{\&tau;}<T-\mathrm{\&omega;}+2{\mathrm{\&omega;}}_0\end{array}\right.$ When, described detection cycle can Two neighboring radar pulse is detected.

Wherein, ω is radar pulse width；ω₀For enable detection time τ that radar pulse is detected with The minimum that radar pulse width ω overlaps；L is integer, represents n-th radar pulse and (n+1)th thunder Reach L detection cycle of inclusion between pulse；N represents radar pulse in the radar pulse cluster of described radar signal Number；P represents the time interval between two adjacent radar pulses.

Embodiments provide a kind of Radar Signal Detection method, by detection cycle cycle detection with reference to letter Whether there is radar signal, described detection cycle includes detection time and free time, when described reference on road When there is radar signal on channel, obtain the radar period of described radar signal, described radar period is adjacent Time interval between two radar pulses, then determines the class of described radar signal according to described radar period Type.Compared to prior art, due to can determine the type of radar signal, therefore, when terminal detects again When there is radar signal on current reference channel, radar signal can be expected according to the type of radar signal Deadline, if now terminal does not also carry out signal transmission on reference channel, this ginseng can not be abandoned Examine channel, and after being to wait for radar signal cut-off, select to carry out signal transmission in this reference channel, so, The utilization rate of the communication resource of reference channel just can be improved；If terminal is being currently used reference channel enters line number According to transmission, and the time of radar signal cut-off is waited to be less than the time that channel switches, then terminal can not be carried out Channel switches, thus avoiding under the signaling rate being caused due to the overlong time that signal transmission is interrupted Fall, improves Consumer's Experience.Simultaneously as free time composition detection cycle is added using detection time, and Using this detection cycle cycle detection reference channel, when radar signal is existed on reference channel, a part of thunder Reach pulse to be detected in the detection time of corresponding detection cycle, therefore may determine that this reference is believed There is radar signal on road, so not needing terminal continual monitoring reference channel, having saved detection energy Amount, further reduces the power consumption of terminal.

The embodiment of the present invention provides a kind of Radar Signal Detection method, is applied to terminal, and described terminal is permissible Using the terminal of LAA communication protocol, can be mobile terminal, such as mobile phone, intelligent watch, or flat board Computer etc.；Can also be fixed terminal, for example, there is the household electrical appliance of communication function, the embodiment of the present invention pair This does not limit.The flow process of described Radar Signal Detection method is as shown in Figure 2：

Step 201, determine detection cycle.

Example, described detection cycle T includes detection time τ and free time t, that is, in detection time τ In, the signal of terminal monitoring channel to be accessed, at one's leisure between in t, terminal is in idle condition, does not supervise Listen the signal of channel to be accessed.So it is not necessary to the continual monitor channel of terminal, saved inspection Survey energy, further reduce the power consumption of terminal.But the radar pulse width due to each radar pulse Very little, if the setting of detection time τ and free time t is unreasonable, can cause in multiple detection cycles, There is no a situation that two neighboring radar pulse is simultaneously detected, the determination of impact radar type it is therefore desirable to Determine suitable detection time τ and free time t, the radar pulse of wherein radar signal is radar pulse.

It is not that radar pulse entirely falls within detection time and can be detected in practical application, by imitative Exact determine when detection time τ and free time t it is assumed that detection probability is 0.9, when signal to noise ratio is 5dB, when ω₀Meet ω₀During=0.25 ω, radar pulse can be detected, wherein ω₀For enabling to described radar arteries and veins Rush the duration that the radar pulse width being detected is overlapped with detection time τ, ω is the radar arteries and veins of radar pulse Rush width, that is, in detection time τ, as long as terminal detects a quarter radar pulse and can determine that detection Arrive radar pulse.

In order to more clearly explain the process determining detection cycle T, define test position, such as Fig. 3 first Shown, for n-th radar pulse signal, test position x_nCaudal end for this radar pulse signal falls During certain detection frame, x in its caudal end time gap foremost to this detection frame, such as Fig. 3_nShown, knot Close to state and enable that radar pulse width that radar pulse is detected is minimum with detection time τ required to be overlapped Duration ω₀=0.25 ω is it is known that in test position x_n∈[ω₀, τ+ω-ω₀) when, this radar pulse signal Just can be detected, therefore, it can define [ω₀, τ+ω-ω₀) for radar pulse detection range.Thus Understand, if desired (n+1)th radar pulse also can be detected by terminal, then x_n+1Need to meet x_n+1∈[ω₀, τ+ω-ω₀).It follows that to continuous two radar pulses, testing conditions is detected For x_n∈[ω₀, τ+ω-ω₀) and x_n+1∈[ω₀, τ+ω-ω₀).

Obvious, as T≤τ+ω -2 ω₀When, that is, $\mathrm{\&tau;}+t\&le;T+\mathrm{\&omega;}-2{\mathrm{\&omega;}}_0\&DoubleRightArrow;t\&le;\mathrm{\&omega;}-2{\mathrm{\&omega;}}_0,$ Even free time t is sufficiently small, less than or equal to ω -2 ω₀When, no matter how long τ is, all can have continuous Two radar pulses are detected.

As T ＞ τ+ω -2 ω₀When, as shown in figure 3, the time interval between two adjacent radar pulses P=LT+p₀, wherein L represent between n-th radar pulse and (n+1)th radar pulse include L examine The survey cycle, p₀Meet 0≤p₀＜ T, represents and removes between n-th radar pulse and (n+1)th radar pulse Cross remaining time interval outside L detection cycle.Wanting of adjacent radar pulse is necessarily detected to meet Ask, need to meet formula (1)：

$\left\{\begin{array}{c}\mathrm{\&tau;}+\mathrm{\&omega;}-2{\mathrm{\&omega;}}_0-p_0\&GreaterEqual;p_0\\ \left(N-1\right)p_0\&GreaterEqual;T\end{array}\right.---\left(1\right)$

Wherein, N represents the number of radar pulse in one radar pulse cluster of radar signal.Formula (1) represents： For any one radar pulse, first radar pulse occurs in any position of whole detection cycle T, All necessarily have a pair continuous radar pulse to simultaneously fall in a monitoring range, and then make two neighboring Radar pulse all can be detected.All restrictive conditions are combined, composition formula (2)：

$\left\{\begin{array}{c}\mathrm{\&tau;}>{\mathrm{\&omega;}}_0\\ T>\mathrm{\&tau;}+\mathrm{\&omega;}-2{\mathrm{\&omega;}}_0\\ p=LT+P_0\\ \mathrm{\&tau;}+\mathrm{\&omega;}-2{\mathrm{\&omega;}}_0-P_0\&GreaterEqual;P_0\\ (N-1)P_0\&GreaterEqual;T\end{array}\right.---\left(2\right)$

Formula (2) is carried out obtaining formula (3) after abbreviation：

$\left\{\begin{array}{c}T\&le;\frac{pN-p}{LN-L+1}\\ max\&lsqb;{\mathrm{\&omega;}}_0,2(p-LT)+2{\mathrm{\&omega;}}_0-\mathrm{\&omega;}\&rsqb;<\mathrm{\&tau;}<T-\mathrm{\&omega;}+2{\mathrm{\&omega;}}_0\end{array}\right.---\left(3\right)$

Wherein, specific simplifying method does not repeat again.When T and τ meets formula (3), certainly have Two adjacent radar pulses can be detected, and can pass through formula (3) and terminal therefore in practical application Common radar type in the region of frequent activities, determines detection cycle T of terminal.

Step 202, by described detection cycle cycle detection reference channel whether there is radar signal；When described When there is radar signal in reference channel, execution step 203；When there is not radar signal in described reference channel, Execution step 205.

By formula (3) or by t arrange sufficiently small when it may be determined that going out detection cycle T, so Afterwards reference channel being detected for loop cycle with described T, example, can be entered using power spectrum flatness method Row detection, describes power spectrum flatness method in detail below by specific computing formula.

General radar signal is square wave, and after ovennodulation to 5GHz, sending signal is as formula (4) Shown：

S (t)=A cos ω_ct (4)

After multipath fading, signal r ' (t) that obtains, expression formula such as formula (5) institute of described r ' (t) Show：

Wherein, v (t) is the radnom elvelope of r ' (t), Rayleigh distributed；Random phase for r ' (t), clothes From being uniformly distributed in [0,2 π].

Not merely only exist signal due on channel, also have some Gaussian noises, therefore in order to obtain accurately Terminal receipt signal in addition it is also necessary on the basis of formula (5) add Gaussian noise, wherein Gaussian noise Formula can be expressed as (6)：

N (t)=n_c(t)cosω_c-n_s(t)sinω_ct (6)

Wherein, n_c(t)、n_sT () is all average is 0, and variance is σ²Gaussian random process, therefore n (t) is also N (t)=R (t) cos [ω can be expressed as_cT+ θ (t)], wherein R (t) and θ (t) is respectively formula (7) and public affairs Shown in formula (8)：

$R\left(t\right)=\sqrt{n_C^2\left(t\right)+n_S^2\left(t\right)}---\left(7\right)$

θ (t)=arc tan [n_s(t)/n_c(t)] (8)

Understand that R (t) meets rayleigh distributed by calculating, that is, meet formula (9), θ (t) obeys in [0,2 π] It is uniformly distributed, wherein formula (9) is：

$P_R\left(r\right)=\frac{r}{{\mathrm{\&sigma;}}^2}\exp (-\frac{r^2}{2{\mathrm{\&sigma;}}^2})---\left(9\right)$

From above-mentioned calculating, final terminal receives during the radar signal of band through multipath fading and plus Gauss Signal after white noise, shown in this receipt signal such as formula (10)：

After terminal receives signal r (t) on reference channel, first signal is sampled, the sampling period For T_s, f_s=1/T_s, sample frequency sample value counts as M, { x₁, x₂……x_M, then carry out DFT (from Scattered Fourier transformation (Discrete Fourier Transform) conversion, obtains frequency-region signal such as formula (11) Shown：

$X\left(t\right)={\mathrm{\&Sigma;}}_{m=0}^{M-1}x\left(m\right)e^{-i\frac{2\mathrm{\&pi;}}{M}km}=R\left(k\right)+jI\left(k\right),k=0,1,...M-1;---\left(11\right)$

Shown in power spectrum signal such as formula (12)：

P (k)=R²(k)+I²(k) (12)

Example, shown in the definition such as formula (13) of power spectrum flatness：

$Ram=\frac{{\mathrm{\&sigma;}}_p^2}{{\mathrm{\&mu;}}_p^2}=\frac{\mathrm{\&Sigma;}{\left(P\right(k)-{\mathrm{\&mu;}}_p)}^2}{{\mathrm{M\&mu;}}_p^2}---\left(13\right)$

Wherein, μ_pMeansigma methodss for P (k), such as shown in formula (14)：

${\mathrm{\&mu;}}_p=\frac{\mathrm{\&Sigma;}P\left(k\right)}{M}---\left(14\right)$

Variance for P (k), such as shown in formula (15)：

${\mathrm{\&sigma;}}_p^2=\frac{\mathrm{\&Sigma;}{\left(P\right(k)-{\mathrm{\&mu;}}_p)}^2}{M}---\left(15\right)$

Generally the power spectrum signal obtaining is asked during flatness it may appear that two kinds of situations：

The first situation, if only having white Gaussian noise on reference channel, obtains after theoretical up-sampling Power spectrum is straight line, so corresponding variances sigma²=0, the therefore flatness of power spectrum is Ram=0； In practical situation, because reference channel can be subject to various interference, so in only noise, receiving The power spectrum of signal fluctuates near straight line up and down at one, the curve of amplitude very little, therefore obtains Variance still very little, Ram tends to 0；

Second situation, if radar signal is existed on reference channel, the power spectrum flatness of receipt signal It is not zero.That assumes power spectrum judges threshold value for Ram₀, then as the Ram >=Ram calculating₀When, Represent there is radar signal on reference channel, and radar pulse is detected, as the Ram ＜ Ram calculating₀ When, represent and radar pulse is not yet detected on reference channel.

In practical application, energy detection method can also be passed through, cyclostationary characteristic detection method, or Join the detection radar signal such as filter detecting method, the embodiment of the present invention does not repeat again.

Step 203, record the time interval between the adjacent radar pulse of each two in described radar signal, hold Row step 204.

Common, radar pulse one by one during the radar signal detecting, therefore receive current After radar pulse, can calculate and the last time receives the time interval between radar pulse.Example, As shown in Figure 3 it is assumed that being currently received (n+1)th radar pulse, then (n+1)th radar pulse and n-th Time interval p=LT+ (T-x between individual radar pulse_n)+x_n+1=(L+1) T+x_n+1-x_n, Time interval p between (n+1)th radar pulse and n-th radar pulse thus can be calculated, then will Time interval between the adjacent radar pulse of each two calculating is recorded, for example, it is possible to by posting Storage or other storage devices are recorded, and the embodiment of the present invention does not limit to this.

In time interval between step 204, the acquisition adjacent radar pulse of each two, minimum time interval is made For radar period, execution step 205.

Example, getting the time interval between (n+1)th radar pulse and n-th radar pulse simultaneously After being recorded, now reference device have recorded that time interval altogether, is the 1st radar pulse respectively Time interval and the 2nd radar pulse between, between the 2nd radar pulse and the 3rd radar pulse Time interval, the time interval between the 3rd radar pulse and the 4th radar pulse ..., (n+1)th Time interval between individual radar pulse and n-th radar pulse, due to during using detection time τ and free time Between t method cycle detection reference channel on signal, be not therefore that each radar pulse can be examined Measure, have some just at one's leisure between t transmission radar pulse may be missed, therefore, terminal detect To n-th radar pulse may not be actual n-th radar pulse, so the n of terminal record Individual time interval is possible and incomplete same, but the time interval that record obtains is only possible to than actual radar Cycle is big it is impossible to the actual radar period of ratio is little, therefore can select the minimum time in n time interval Interval is as radar period, because minimum time interval in n time interval is exactly the possibility of radar period Property maximum.Terminal often detects a radar pulse and just records a time interval, then from the time of record As radar period, so, radar period is real-time update to the time interval finding minimum in interval, Be forever record time interval in minimum, it is to avoid because radar period obtains the confirmation thunder that mistake leads to Reach the error of type.

Step 205, judge to detect duration whether more than or equal to reference to duration；When detection duration is more than or waits When with reference to duration, execution step 206；When detecting that duration is less than with reference to duration, execution step 202.

Common, when terminal needs to carry out signal transmission, choose any one channel first, detect this letter Radar signal be whether there is on road, the embodiment of the present invention illustrates taking reference channel as a example, when terminal detection When selected reference channel whether there is radar signal, because radar signal is radar pulse form, if When terminal starts to detect, the interval time of precisely radar pulse twice, then cannot accurately detect and whether there is , it is therefore desirable to persistently be detected in certain time length, the embodiment of the present invention is with a length of during reference for radar signal Example illustrates it is generally the case that can be availability inspection on described reference channel for the terminal with reference to duration The survey time (Channel Availability Check time, CAC) or redefine other when Long, the embodiment of the present invention does not limit to this.

Step 206, judge described with reference to whether being completely absent described radar signal in duration；When described ginseng Examine when there is described radar signal in duration, execution step 207；When described with reference to being completely absent in duration During described radar signal, execution step 209.

Due to radar pulse form during radar signal, and when terminal detects to reference channel first, It is not aware that radar signal is expected transmission at what time it is possible to detect in a period of time after starting, eventually End never detects radar signal, but detects first radar of radar signal after this time Pulse, is not at this moment not have radar signal completely in reference duration, but there is thunder within rear a period of time Reach signal, therefore when terminal detect there is no radar signal on reference channel when, first determine whether detect duration be No more than or equal to reference to duration, when detecting that duration is more than or equal to reference to duration, confirm with reference in duration Whether it is not detected by radar signal completely, it is to avoid because detection is judged by accident currently without radar pulse with reference to letter Radar signal is not existed on road.

Step 207, determine the type of described radar signal according to described radar period, execution step 208.

Common, when the type of radar signal is different, radar period is different, therefore can be by radar week Phase determines the type of radar signal.After detection duration is more than or equal to reference to duration, terminal obtains detection The radar period updating to after last radar pulse, then determines currently in ginseng according to this radar period Examine the type of the radar signal of channel.

The radar type of reference channel described in step 208, labelling, terminates currently processed flow process.

Common, only transmit a type of radar signal in order to avoid on one channel of interference, because when determination After going out the type of radar signal, represent that the radar signal of transmission on reference channel is exactly and such, Do not wash in a pan on this reference channel and be likely to occur other kinds of radar signal, therefore can be to this ginseng with terminal Examine channel to be marked, so although present terminal can not change transmission signal on reference channel again, but It is when next terminal needs transmission signal on this reference channel, detect whether deposit first on this channel current In radar signal, when there is radar signal on this channel, terminal can judge according to the type of radar signal The deadline of this radar signal, it is then determined that when signal transmission can be carried out on this reference channel, In the case of judging that this radar signal is ended quickly, can select to wait, end in radar signal laggard Row signal transmission, it is to avoid reselect the waste of the communication resource that channel causes, when judging that this radar believes When number also needing to be lot more time to enough cut-offs, other channels are selected rapidly to be transmitted.Meanwhile, work as terminal When carrying out signal transmission, if currently occurring in that radar signal, terminal can be expected thunder according to radar type Reach the deadline of signal, if waiting the time of radar signal cut-off to be less than the time switching channel, eventually End can not carry out channel switching, and proceeds signal transmission after being to wait for radar signal cut-off；If waited Treat that the time of radar signal cut-off is more than the time of switching channel, then terminal can carry out channel switching rapidly, Make the time that signal transmission is interrupted shorter as far as possible, improve Consumer's Experience.

Step 209, signal transmission is carried out on described reference channel.

In with reference to duration, reference channel is not detected by radar pulse completely, then explanation current reference letter Radar signal is not had to be transmitted on road, terminal can carry out signal transmission on this reference channel.In terminal When carrying out signal transmission, can persistently monitor the signal on reference channel, when radar pulse occurs, according to Method provided in an embodiment of the present invention determines the type of radar signal, or can also select to switch channel, this Inventive embodiments do not limit to this.

Embodiments provide a kind of Radar Signal Detection method, methods described is followed by detection cycle first Whether there is radar signal, described detection cycle includes detection time and free time on ring detection reference channel, When there is radar signal on described reference channel, obtain the radar period of described radar signal, described radar Cycle is the time interval between two neighboring radar pulse, then determines described thunder according to described radar period Reach the type of signal.Compared to prior art, due to can determine the type of radar signal, therefore, work as end End detects when there is radar signal on current reference channel again, can be expected according to the type of radar signal The deadline of radar signal, if now terminal does not also carry out signal transmission on reference channel, permissible Do not abandon this reference channel, and after being to wait for radar signal cut-off, select to carry out signal in this reference channel Transmission, so, just can improve the utilization rate of the communication resource of reference channel；If terminal is being currently used ginseng Examine channel to carry out data transmission, and wait the time of radar signal cut-off to be less than the time that channel switches, then eventually End can not carry out channel switching, thus avoiding the signal causing due to the overlong time that signal transmission is interrupted The decline of transmission speed, improves Consumer's Experience.Simultaneously as free time composition is added using detection time Detection cycle, and utilize this detection cycle cycle detection reference channel, when radar signal is existed on reference channel When, a part of radar pulse can be detected in the detection time of corresponding detection cycle, therefore can sentence Break and there is radar signal on this reference channel, so not needing terminal continual monitoring reference channel, Save detection energy, further reduce the power consumption of terminal.

The embodiment of the present invention provides a kind of Radar Signal Detection device 40, as shown in figure 4, including：

Detector unit 401, for whether there is radar signal by detection cycle cycle detection reference channel, Described detection cycle includes detection time and free time, and described radar signal includes multiple radar pulses.

Acquiring unit 402, for when there is radar signal on described reference channel, obtaining described radar letter Number radar period, described radar period is the time interval between two neighboring radar pulse.

Determining unit 403, for determining the type of described radar signal according to described radar period.

So, because terminal can determine the type of radar signal, therefore work as when terminal detects again The cut-off of radar signal when there is radar signal on front reference channel, can be expected according to the type of radar signal Time, if now terminal does not also carry out signal transmission on reference channel, this reference letter can not be abandoned Road, and it is to wait for radar signal by afterwards, select to carry out signal transmission in this reference channel, improve ginseng Examine the utilization rate of the communication resource of channel；If terminal is being currently used reference channel and carries out data transmission simultaneously, If the time waiting radar signal cut-off is less than the time that channel switches, terminal can not carry out channel switching, Avoid the decline of signaling rate causing due to the overlong time that signal transmission is interrupted, improve user Experience.

In practical application, described Radar Signal Detection device 40 can be arranged on terminal inner, by terminal Controller is uniformly controlled it is also possible to be arranged on the outside of terminal, is entered with terminal by external communication interface Row communication, this year inventive embodiments are not construed as limiting to this.

Preferably, described acquiring unit 402 specifically for：

When there is radar signal on described reference channel, record the adjacent radar of each two in described radar signal Time interval between pulse；

Obtain minimum time interval in the time interval between the adjacent radar pulse of described each two as described Radar period.

Optionally, described detector unit 401 specifically for：

Obtain the signal on described reference channel in the detection time with reference to detection cycle, described all with reference to detection Phase is any one detection cycle described；

The power spectrum of the signal on described reference channel in the described detection time with reference to detection cycle of acquisition is flat Degree；

When described power spectrum flatness is more than reference threshold, described reference channel is described with reference to detection cycle Detection time in radar pulse is detected；

When described power spectrum flatness is less than reference threshold, described reference channel is described with reference to detection cycle Detection time in be not detected by radar pulse.

Further, as shown in figure 5, described device 40 also includes：

Whether the first judging unit 404, for judging to detect duration more than or equal to reference to duration, described inspection The time of reference channel described in a length of cycle detection as detection cycle during survey；

Described determining unit 403 specifically for when described detection duration be more than or equal to described with reference to duration when, Determine the type of described radar signal according to described radar period.

Further, as shown in fig. 6, described device 40 also includes：

Second judging unit 405, for when there is not radar signal on described reference channel, judging detection Whether duration is more than or equal to reference to duration, reference described in a length of cycle detection as detection cycle during described detection The time of channel；

3rd judging unit 406, for when described detection duration is more than or equal to described reference duration, sentencing Whether the described reference channel that breaks is completely absent described radar signal in described detection duration；

Transmission unit 407, for when described detection duration in whether be completely absent described radar signal when, Signal transmission is carried out by described reference channel.

Example, described detection cycle T=τ+t, τ are detection time, and t is free time, described detection week Phase T meets formula one, or meets formula two；

Formula one is：T≤τ+ω-2ω₀；

Wherein, ω is radar pulse width, ω₀For enable detection time τ that radar pulse is detected with The minimum that radar pulse width ω overlaps；

Formula two is： $\left\{\begin{array}{c}T\&le;\frac{pN-p}{LN-L+1}\\ max\&lsqb;{\mathrm{\&omega;}}_0,2(p-LT)+2{\mathrm{\&omega;}}_0-\mathrm{\&omega;}\&rsqb;<\mathrm{\&tau;}<T-\mathrm{\&omega;}+2{\mathrm{\&omega;}}_0\end{array}\right.;$

Wherein, ω is radar pulse width；ω₀For enable detection time τ that radar pulse is detected with The minimum that radar pulse width ω overlaps；L is integer, represents n-th radar pulse and (n+1)th thunder Reach L detection cycle of inclusion between pulse；N represents radar pulse in the radar pulse cluster of described radar signal Number；P represents the time interval between two adjacent radar pulses.

Embodiments provide a kind of Radar Signal Detection device, described device includes：Detector unit, For by whether there is radar signal on detection cycle cycle detection reference channel, described detection cycle includes examining Survey time and free time；Acquiring unit, for when there is radar signal on described reference channel, obtaining The radar period of described radar signal, described radar period is the time interval between two neighboring radar pulse； Determining unit, for determining the type of described radar signal according to described radar period.Compared to prior art, Due to can determine the type of radar signal, therefore, exist on current reference channel when terminal detects again The deadline of radar signal during radar signal, can be expected according to the type of radar signal, if now terminal When also not carrying out signal transmission on reference channel, this reference channel can not be abandoned, and be to wait for radar After signal cut-off, select to carry out signal transmission in this reference channel, so, just can improve reference channel The utilization rate of the communication resource；If terminal is being currently used reference channel carrying out data transmission, and wait radar The time of signal cut-off is less than the time of channel switching, then terminal can not carry out channel switching, thus avoiding Due to the decline of the signaling rate that the overlong time that signal transmission is interrupted causes, improve Consumer's Experience.

It should be noted that the concrete device purposes of device side embodiment refer to the description of method side embodiment, The embodiment of the present invention is not detailed in device side.And, in actual applications, described detector unit 401, Acquiring unit 402, determining unit 403, the first judging unit 404, the second judging unit the 405, the 3rd are sentenced Disconnected unit 406 all can by the central processing unit (Central Processing Unit, CPU) in mobile terminal, Microprocessor (Micro Processor Unit, MPU), digital signal processor (Digital Signal Processor, DSP) or field programmable gate array (Field Programmable Gate Array, FPGA) etc. is realized, Transmission unit 407 can be realized by antenna, emitter etc..

The above, only presently preferred embodiments of the present invention, it is not intended to limit the protection model of the present invention Enclose.

Claims (12)

1. a kind of Radar Signal Detection method is it is characterised in that methods described includes：

By whether there is radar signal on detection cycle cycle detection reference channel, described detection cycle includes examining Survey time and free time, described radar signal includes multiple radar pulses；

When there is radar signal on described reference channel, obtain the radar period of described radar signal, described Radar period is the time interval between two neighboring radar pulse；

Determine the type of described radar signal according to described radar period.

2. method according to claim 1 it is characterised in that described when on described reference channel exist During radar signal, the radar period obtaining described radar signal includes：

When there is radar signal on described reference channel, record the adjacent radar of each two in described radar signal Time interval between pulse；

Obtain minimum time interval in the time interval between the adjacent radar pulse of described each two as described Radar period.

3. method according to claim 1 and 2 is it is characterised in that described circulate inspection by detection cycle Survey and include with the presence or absence of radar signal on reference channel：

Obtain the signal on described reference channel in the detection time with reference to detection cycle, described all with reference to detection Phase is any one detection cycle；

The power spectrum of the signal on described reference channel in the described detection time with reference to detection cycle of acquisition is flat Degree；

When described power spectrum flatness is more than reference threshold, described reference channel is described with reference to detection cycle Detection time in radar pulse is detected；

When described power spectrum flatness is less than reference threshold, described reference channel is described with reference to detection cycle Detection time in be not detected by radar pulse.

4. method according to claim 2 it is characterised in that described acquisition described each two adjacent After in time interval between radar pulse, minimum time interval is as described radar period, methods described Also include：

Judge to detect duration whether more than or equal to reference to duration, during described detection a length of by detection cycle circulation Detect the time of described reference channel；

Described included according to the type that described radar period determines described radar signal：

When described detection duration is more than or equal to described reference duration, according to described radar period determines The type of radar signal.

5. method according to claim 1 and 2 is it is characterised in that described by detection cycle circulation With the presence or absence of after radar signal on detection reference channel, methods described also includes：

When there is not radar signal on described reference channel, judge to detect whether duration is more than or equal to reference Duration, the time of reference channel described in a length of cycle detection as detection cycle during described detection；

When described detection duration is more than or equal to described reference duration, judge described reference channel in described inspection Survey in duration and whether be completely absent described radar signal；

When whether being completely absent described radar signal in described detection duration, entered by described reference channel Row signal transmission.

6. method according to claim 1 and 2 is it is characterised in that described detection cycle T=τ+t, τ is detection time, and t is free time, and described detection cycle T meets formula：T≤τ+ω-2ω₀；

Wherein, ω is radar pulse width, ω₀For enable detection time τ that radar pulse is detected with The minimum that ω overlaps；

Or, described detection cycle T meets formula：

$\left\{\begin{array}{c}T\&le;\frac{pN-p}{LN-L+1}\\ max\&lsqb;{\mathrm{\&omega;}}_0,2(p-LT)+2{\mathrm{\&omega;}}_0-\mathrm{\&omega;}\&rsqb;<\mathrm{\&tau;}<T-\mathrm{\&omega;}+2{\mathrm{\&omega;}}_0\end{array}\right.;$

Wherein, ω is radar pulse width；ω₀For enable detection time τ that radar pulse is detected with The minimum that ω overlaps；L is integer, represents and wraps between n-th radar pulse and (n+1)th radar pulse Include L detection cycle；N represents the number of radar pulse in the radar pulse cluster of described radar signal；P table Show the time interval between two adjacent radar pulses.

7. a kind of Radar Signal Detection device is it is characterised in that described device includes：

Detector unit, for by radar signal be whether there is on detection cycle cycle detection reference channel, described Detection cycle includes detection time and free time, and described radar signal includes multiple radar pulses；

Acquiring unit, for when there is radar signal on described reference channel, obtaining described radar signal Radar period, described radar period is the time interval between two neighboring radar pulse；

Determining unit, for determining the type of described radar signal according to described radar period.

8. device according to claim 7 it is characterised in that described acquiring unit specifically for：

When there is radar signal on described reference channel, record the adjacent radar of each two in described radar signal Time interval between pulse；

Obtain minimum time interval in the time interval between the adjacent radar pulse of described each two as described Radar period.

9. the device according to claim 7 or 8 it is characterised in that described detector unit specifically for：

Obtain the signal on described reference channel in the detection time with reference to detection cycle, described all with reference to detection Phase is any one detection cycle described；

The power spectrum of the signal on described reference channel in the described detection time with reference to detection cycle of acquisition is flat Degree；

When described power spectrum flatness is more than reference threshold, described reference channel is described with reference to detection cycle Detection time in radar pulse is detected；

When described power spectrum flatness is less than reference threshold, described reference channel is described with reference to detection cycle Detection time in be not detected by radar pulse.

10. device according to claim 8 is it is characterised in that described device also includes：

First judging unit, for judging whether to detect duration more than or equal to reference duration, during described detection The time of reference channel described in a length of cycle detection as detection cycle；

Described determining unit specifically for when described detection duration be more than or equal to described with reference to duration when, according to Described radar period determines the type of described radar signal.

11. devices according to claim 7 or 8 are it is characterised in that described device also includes：

Second judging unit, for when there is not radar signal on described reference channel, judging detection duration Whether more than or equal to reference to duration, reference channel described in a length of cycle detection as detection cycle during described detection Time；

3rd judging unit, for when described detection duration is more than or equal to described reference duration, judging institute State whether reference channel is completely absent described radar signal in described detection duration；

Transmission unit, for when whether being completely absent described radar signal in described detection duration, passing through Described reference channel carries out signal transmission.

12. devices according to claim 7 or 8 it is characterised in that described detection cycle T=τ+t, τ is detection time, and t is free time, and described detection cycle T meets formula：T≤τ+ω-2ω₀；

Wherein, ω is radar pulse width, ω₀For enable detection time τ that radar pulse is detected with The minimum that ω overlaps；

Or, described detection cycle T meets：

$\left\{\begin{array}{c}T\&le;\frac{pN-p}{LN-L+1}\\ max\&lsqb;{\mathrm{\&omega;}}_0,2(p-LT)+2{\mathrm{\&omega;}}_0-\mathrm{\&omega;}\&rsqb;<\mathrm{\&tau;}<T-\mathrm{\&omega;}+2{\mathrm{\&omega;}}_0\end{array}\right.;$

Wherein, ω is radar pulse width；ω₀For enable detection time τ that radar pulse is detected with The minimum that ω overlaps；L is integer, represents and wraps between n-th radar pulse and (n+1)th radar pulse Include L detection cycle；N represents the number of radar pulse in the radar pulse cluster of described radar signal；P table Show the time interval between two adjacent radar pulses.