CN101043235A - Method for controlling emission power of pilot signal - Google Patents

Abstract

The invention discloses a pilot frequency signal emission power control method that comprises: ensuring the plus value of pilot frequency signal; multiplying said plus value of pilot frequency signal with pilot frequency sequence to obtain the pilot frequency sequence gained; the base band sending end sends the pilot frequency sequence gained. The invention adopts the intermediate frequency clipping threshold and linear work point range of power amplifier to ensure the plus value of pilot frequency signal, takes use of linear amplification resource of power amplifier, increases the emission power of pilot frequency signal, improves the Signal-to-Noise and decreases the distortion of the pilot frequency signal, the receiving end can receive and renew the pilot frequency signal better.

Description

A kind of pilot signal transmission power control method

technical field

The present invention relates to the communication field, in particular to a pilot signal transmission power control method in an Orthogonal Frequency Division Multiplexing (OFDM) system.

Background technique

In recent years, broadband wireless communication technology and application have developed rapidly, and people's demand for wireless data multimedia services has promoted the development and application of new technologies for high-speed broadband wireless communication. OFDM technology and multiple-input multiple-output (MIMO) technology have been or will be used in various high-speed broadband wireless communication systems.

The idea of frequency division multiplexing and parallel data transmission first appeared in the 1960s. After more than 40 years of research and development, OFDM has become a widely used high-speed data transmission technology. One of the most important techniques used is the Fast Fourier Transform (FFT). It greatly reduces the difficulty of parallel data modulation and demodulation, thus making it possible to use OFDM in large quantities.

The basic idea of OFDM is to disperse the data that needs to be transmitted to a large number of subcarriers that are transmitted at the same time. Although each subcarrier uses a lower rate modulation method, due to the large number of subcarriers, high-speed data transmission can be used as a whole. The orthogonality between these sub-carriers is realized by selecting the frequency spectrum spacing appropriately.

At present, the relevant technology combining OFDM and MIMO has completed standard formulation in IEEE802.16. In addition, in the mobile wireless communication access system, the wireless access network of the Third Generation Partnership Project (3GPP) and the physical layer of IEEE 802.20 are also considering the use of OFDM technology and MIMO technology to build mobile devices with higher frequency efficiency. Wireless communication access system.

The data transmission system using OFDM technology has the following advantages:

1) It has strong fault tolerance to multipath delay extension. As shown in Figure 1, an OFDM symbol includes two parts in the time domain: the data part and the cyclic prefix part. The cyclic prefix part is generated cyclically at the end of the _data part. The time taken is T _cp . The fault tolerance of OFDM technology is manifested in: compared with the duration Ts of an OFDM symbol, the duration of the typical channel impulse response is very small, and only occupies a small part of Ts, so it can be increased by adding a smaller cyclic prefix, namely T _cp , to completely overcome the interference between signals caused by multipath.

2) It has strong fault tolerance to frequency selective fading. OFDM technology can recover digital signals carried by strongly fading sub-carriers by using redundant schemes such as channel coding.

3) A simple equalization algorithm is adopted. Since OFDM technology uses the frequency domain to transmit signals, and the role of the channel in the frequency domain is represented by simple multiplication, so that the data transmission system using OFDM technology only needs a simple single-tap equalizer when performing signal equalization. .

4) Compared with frequency division multiplexing (FDM) technology, OFDM technology has higher spectral efficiency.

In the current OFDM system pilot design, two pilot design methods are mainly used, one is staggered pilot (Stagger-Type) or comb-shaped pilot (Comb-Type), and the other is block pilot (Block-Type), as shown in Figure 2, for the pilot frequency of Block-Type, in the prior art, a single transmit power is mainly used, and the transmit power is obtained according to a certain proportional relationship with the transmit power of the data part. Constant value. That is to say, this constant value is pre-written into the baseband transmitter in advance, and the baseband transmitter will transmit the pilot signal with the power of this constant value.

The above-mentioned pilot signal transmission in the prior art has the following disadvantages:

Since the peak to average power ratio (PAPR) value of OFDM technology may be very large, in fact, the dynamic range of the transmitter is quite large, so that to be able to transmit OFDM data signals normally, it may be necessary to choose a relatively working A power amplifier with a large point linear range, and if the baseband of the pilot signal only uses a single power at this time, the following problems will occur:

(1) If the transmission power of the pilot signal is low, and the transmitter has a large linear range, since the power range of the transmitted pilot only accounts for a small part of it, the large linear range cannot be fully utilized range, it will cause waste of power amplifier resources within a certain range; at the same time, due to the low transmission power, the signal-to-noise ratio at the receiving end is small, so the pilot signal may not be well received and processed at the receiving end, making the pilot signal It completely loses its due role and functions it should complete.

(2) If the transmission power of the pilot signal is high, in order to protect the power amplifier and deal with the nonlinear distortion of the signal caused by the power amplifier, the intermediate frequency part will set an intermediate frequency clipping threshold through the operating point of the power amplifier and the average power of the baseband signal. When the baseband signal sent to the IF is greater than the IF clipping threshold, the IF part will process the signal through a set of IF clipping algorithms to ensure that it is within the threshold. Although the processed signal can be guaranteed to be within the threshold, it also causes distortion of the processed signal. Similarly, the clipping processing of the pilot signal will also cause distortion, and even introduce in-band and out-of-band noise. After the pilot signal is distorted, the receiving end cannot recover and process the pilot information correctly. In addition, when the operating point range of the power amplifier at the transmitter end is not very high, the power amplifier may be damaged due to excessive power.

Contents of the invention

The present invention provides a pilot signal transmission power control method, which is used to solve the problem in the prior art that the pilot signal only refers to the transmission power of the data part and adopts a fixed power value to transmit, resulting in waste of resources, low signal-to-noise ratio at the receiving end or signal failure. Distortion problem.

The inventive method comprises:

A. Determine the pilot signal gain value;

B. Multiply the gain value of the pilot signal by the pilot sequence to obtain the gained pilot sequence and send it.

Described step A comprises:

The baseband transmitting end determines the gain value of the pilot signal according to the intermediate frequency clipping threshold and the linear operating range of the power amplifier; the power value of the pilot sequence after the gain satisfies the power value less than or equal to the intermediate frequency clipping threshold, and is less than or equal to the power The maximum input power value for the amplifier's linear operating range.

Described step A comprises:

The baseband transmitting end continuously or periodically acquires the intermediate frequency clipping threshold and the linear operating range of the power amplifier, and updates the determined pilot signal gain value; the power value of the pilot sequence after the gain satisfies the power value less than or equal to the intermediate frequency clipping threshold , and is less than or equal to the maximum input power value of the linear operating range of the power amplifier.

According to the above method of the present invention, a plurality of optional gain values are preset;

Multiplying the optional gain values by the time-domain power peak values of the pilot sequence respectively to obtain multiple corresponding gain result values;

Determine a gain result value that is the closest to the intermediate frequency clipping threshold power value and the closest to the maximum input power value in the linear range of the power amplifier among the plurality of gain result values;

The determined optional gain value corresponding to the gain result value is used as the pilot signal gain value.

According to the above method of the present invention, after the step A, it further includes: the baseband transmitting end notifies the receiving end of the determined gain value of the pilot signal;

After the step B, the method further includes: after the receiving end receives the pilot signal, it performs an inverse operation of the corresponding gain multiple according to the gain value to restore the pilot signal.

The baseband transmitting end notifies the receiving end of the determined pilot signal gain value, the specific method is:

The baseband transmitting end sends a pilot signal gain value notification message to the receiving end, carrying the determined pilot signal gain value information; after receiving the notification message, the receiving end parses out the carried pilot signal gain value; or

The baseband transmitting end carries identification information representing the gain value of the pilot signal through existing signaling, and the receiving end analyzes the identification information to obtain the corresponding gain value of the pilot signal.

The identification information is a binary number occupying N bits; after receiving the N bits, the receiver determines the gain value corresponding to the N-bit binary number according to the pre-agreed correspondence with the baseband transmitter.

The number of bits N occupied by the identification information is determined according to the number of gain values agreed upon between the sending end and the receiving end of the base station.

The step B includes: directly multiplying the baseband frequency domain pilot signal with the pilot signal gain value by a multiplier to obtain the gained pilot frequency domain signal, and then perform the inverse fast Fourier transform IFFT to obtain the gained pilot time domain signal, which is sent after being processed by the middle radio frequency processing part; or

The baseband frequency domain pilot signal is first subjected to IFFT transformation, transformed into the time domain and then multiplied by the gain value of the pilot signal through a multiplier to obtain the gained pilot time domain signal, which is processed by the middle radio frequency processing part and sent .

After receiving the time-domain pilot signal, the receiving end performs fast Fourier transform (FFT) to obtain the frequency-domain pilot signal, and then performs the inverse operation of the corresponding gain multiple to recover the pilot signal.

According to the above method of the present invention, before the step A, it further includes: selecting a digital sequence with a smaller peak-to-average power than PAPR value as the pilot sequence.

The digital sequence with a smaller PAPR value can be generated by a 13-bit PN sequence generator.

According to the above method of the present invention, for a multi-antenna transmission system, in the step B, the baseband transmitting end sends the gained pilot sequence to each antenna; The sequence is multiplied by the corresponding phase rotation factor and then IFFT transformed and then sent.

The beneficial effects of the present invention are as follows:

(1) When the present invention transmits the pilot signal, the baseband transmitting end first determines a suitable pilot signal gain value according to the linear operating range of the intermediate frequency clipping threshold and the power amplifier; The multiplied frequency sequence is multiplied to obtain the pilot sequence after gain; the power value of the pilot sequence after gain is satisfied to be less than or equal to the intermediate frequency clipping threshold power value, and less than or equal to the maximum input power value of the linear operating range of the power amplifier. In this way, the pilot signal transmitted at the baseband transmitting end will not be clipped due to exceeding the intermediate frequency clipping threshold, resulting in distortion; at the same time, the power amplifier will be protected because it will not exceed the linear operating range of the power amplifier.

(2) The present invention multiplies the optional gain values by the time-domain power peak values of the pilot sequence by presetting multiple optional gain values to obtain corresponding multiple gain result values; A gain result value that is closest to the intermediate frequency clipping threshold power value and the maximum input power value in the linear range of the power amplifier; the optional gain value corresponding to the determined gain result value is used as the pilot signal gain value. In this way, not only the pilot signal will not be clipped by the intermediate frequency to avoid signal distortion, but also the maximum possible transmission power is used for transmission, which improves the efficiency of the power amplifier and the signal-to-noise ratio of the pilot signal received by the receiving end. So that the receiving end can better receive and recover the pilot signal.

Description of drawings

Fig. 1 is a schematic diagram of OFDM symbol composition;

Figure 2 is a schematic diagram of Block-Type pilot transmission;

Fig. 3 is one of flowcharts of the method embodiment of the present invention;

Fig. 4 is the second flow chart of the method embodiment of the present invention.

Detailed ways

The pilot signal transmission power control method provided by the present invention includes:

Determine the pilot signal gain value;

multiplying the pilot signal gain value by the pilot sequence to obtain the gained pilot sequence;

The baseband transmitter sends the gained pilot sequence.

The above-mentioned method of the present invention will be described in detail below with specific embodiments in conjunction with the accompanying drawings.

Example 1:

Referring to Fig. 3, it is a flow chart of the steps of Embodiment 1 of the present invention. In Embodiment 1, after the pilot signal gain value is determined once, it will not be changed; the specific steps include:

Step S11, selecting a data sequence with a smaller PAPR value as a pilot sequence.

The formula for the PAPR value of the pilot sequence is as follows:

$\mathrm{<span\; class="notranslate">\; PAPR</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; max</span>}<span\; class="notranslate">\; \{</span>{<span\; class="notranslate">\; |</span>\mathrm{<span\; class="notranslate">\; S</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; \}</span>}{\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; N</span>}}\underset{\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{<span\; class="notranslate">\; |</span>\mathrm{<span\; class="notranslate">\; S</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

In formula (1): $S\left(k\right)=\underset{\mathrm{no}=0}{\overset{N-1}{\mathrm{\&Sigma;}}}{a}_{\mathrm{no}}{e}^{j2\mathrm{\&pi;}\frac{\mathrm{nk}}{N}}$

Using a pilot sequence with a smaller PAPR value can reduce the loss of the pilot signal when it is transmitted at the transmitting end, and can also reduce the difficulty of processing the pilot signal at the transmitting end and the receiving end, and improve the processing speed of the pilot signal. For example: a 13Bit PN sequence generator can be used to generate a pilot sequence:

h(d)＝1+D ⁸ +D ¹¹ +D ¹² +D ¹³

Step S12 , the baseband transmitter obtains the IF clipping threshold and the linear operating range of the power amplifier, and determines the gain value of the pilot signal.

The baseband transmitting end obtains the IF clipping threshold set by the system, or calculates the IF clipping threshold through the statistical characteristics of the baseband signal (the specific calculation method of the IF clipping threshold is the prior art, and will not be described in detail here), and simultaneously passes The linear range of the operating point of the feedback power amplifier in the mid-radio frequency processing part; the baseband transmitter determines an appropriate gain constant value at one time according to the mid-frequency clipping threshold power value and the maximum input power value of the linear range of the power amplifier; specific methods such as:

Assuming that the intermediate frequency clipping threshold power value is A, the maximum input power value in the linear range of the power amplifier is B, and the baseband calculates the maximum power value of the pilot frequency in the time domain by performing inverse fast Fourier transform (IFFT) on the frequency domain pilot signal. And pre-set a set of gain multiples D=(d ₁ , d ₂ , d ₃ ...d _n ), then it is necessary to select an appropriate gain constant value from the D sequence as the gain value of the pilot signal, the gain constant value At least the following two conditions must be met:

Condition 1: The product of the gain multiple d _m (d _m ∈ D) and the maximum power value (power peak value) C in the time domain of the above-mentioned pilot signal is less than or equal to the above-mentioned clipping threshold power value A and the maximum input power value B of the power amplifier; that is :

d _m ×C≤A (2)

d _m ×C≤B (3)

That is, formula (2) and formula (3) are satisfied at the same time; that is, d _m ×C must be less than or equal to the smaller value of the clipping threshold power value A and the maximum input power value B of the power amplifier; assuming B< A, then d _m ×C must satisfy formula (3).

Satisfying condition 1 can ensure that the pilot signal will not be distorted at the transmitting end due to IF clipping or nonlinearity of the power amplifier, and avoid the problem that the pilot signal cannot be recovered normally after the pilot signal received at the receiving end is distorted.

Condition 2: The selected d _m is the maximum value in the D sequence that satisfies the conditions of formula (2) and formula (3). Assumptions:

d ₁ < d ₂ < d ₃ ... < d _n (4)

And assuming B<A, then use formula (3) in condition 1, assuming that d ₂ and d ₁ are two gain multiple values satisfying formula (3); then according to condition 2, take the D sequence that satisfies condition 1 The maximum value of , from formula (4) we can see that d ₂ is determined as the pilot signal gain value among d ₂ and d ₁ .

Satisfying condition 2 is to ensure that the linear range resources of the power amplifier are fully utilized, so that the transmitting end uses a larger power to transmit the pilot signal as much as possible, thereby improving the signal-to-noise ratio of the receiving end, so that the receiving end can receive and restore the pilot signal as well as possible. frequency signal.

Step S13, the baseband transmitting end notifies the receiving end of the determined pilot signal gain value. Specific methods such as:

The baseband transmitting end sends a pilot signal gain value notification message to the receiving end, carrying the determined pilot signal gain value information; after receiving the notification message, the receiving end analyzes the carried pilot signal gain value.

Alternatively, the baseband transmitting end carries identification information indicating the gain value of the pilot signal through existing signaling, and the receiving end analyzes the identification information to obtain the corresponding gain value of the pilot signal.

The identification information can be represented by a binary number occupying N bits; after receiving the N bits, the receiver determines the gain value corresponding to the N-bit binary number according to the pre-agreed correspondence with the baseband transmitter. The number of bits N occupied by the identification information may be determined according to the number of gain values agreed between the base station sending end and the receiving end. For example: the baseband transmitter and receiver agree on several corresponding gain values in advance, and use N Bits to represent these gain values, for example, use 2 Bits to identify the corresponding gain values:

00 means the gain value is 1 or no gain;

01 means the gain value is 2 times;

10 means the gain value is 4 times;

11 means the gain value is 8 times.

How many bits are used to identify the gain value can be determined according to the number of gain values agreed between the two. If the agreed number of gain values is 4, 2 bits can be used to identify the corresponding gain value; If the agreed number of gain values is 8, then 3 Bits can be used to identify the corresponding gain value; and so on.

Step S14 , the baseband transmitting end multiplies the appropriate pilot signal gain value determined at one time by the pilot sequence to obtain a gained pilot sequence, and sends the gained pilot sequence to the receiving end.

The specific processing method can be:

1. The baseband frequency domain pilot signal is directly multiplied by the gain value of the pilot signal through a multiplier to obtain the gained pilot frequency domain signal, and then the inverse fast Fourier transform (IFFT) is performed to obtain the gained pilot time domain signal, which is sent to Send it to the RF processing part and send it out;

2. Perform IFFT transformation on the baseband frequency domain pilot signal first, and then gain with the pilot signal after transforming into the time domain. The values are multiplied by a multiplier to obtain a pilot time-domain signal after gain, and then sent to the middle radio frequency part for processing and sent out.

The baseband transmitter will always process the pilot sequence with this gain value.

Step S15 , after receiving the pilot sequence, the receiving end performs an inverse calculation of the corresponding gain multiple according to the obtained pilot signal gain value, and restores the pilot signal. Specifically:

After receiving the pilot signal in the time domain, fast Fourier transform (FFT) is performed first to obtain the pilot signal in the frequency domain, and then the inverse operation of the corresponding gain multiple is performed to restore the pilot signal.

For a multi-antenna transmission system, the baseband transmitter sends the gained pilot sequence to each antenna; each antenna multiplies the gained pilot sequence by the corresponding phase rotation factor in the frequency domain, and then performs IFFT transformation before transmitting .

For example: Each antenna processes the pilot signal by cyclic shifting method:

${\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; j</span>}\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&pi;k</span>}{\mathrm{<span\; class="notranslate">\; \&Delta;t</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}}}$

Among them, m is the number of the m-th antenna, S _m (k) is the pilot signal to be sent on the m-th antenna, k is the index number of the subcarrier in the frequency domain, and Δt _m is the cycle of the m-th antenna in the frequency domain The shifted coefficient is reflected as a delay factor in the time domain.

The above-mentioned embodiment 1 is mainly aimed at a system in which the performance of the power amplifier and the IF processing parameters do not change or do not change greatly. In this case, the gain value of the pilot signal can be selected at one time and will not be changed again. However, for a system where the performance of the power amplifier changes greatly, or the update frequency of the intermediate frequency processing parameters is high, the method of selecting the gain value at one time and not changing it is no longer suitable, and the method in the following embodiment 2 needs to be adopted.

Embodiment 2: The baseband transmitting end acquires the intermediate frequency clipping threshold and the linear operating range of the power amplifier continuously or periodically, and updates the determined gain value of the pilot signal. Its specific implementation steps are shown in Figure 4, including:

Step S21 is the same as step S11 in FIG. 3 and will not be described again.

Step S22 , the baseband transmitter continuously or periodically acquires the IF clipping threshold and the linear operating range of the power amplifier, and determines the gain value of the pilot signal. The specific method for determining the gain value of the pilot signal may be the same as step S12 in FIG. 3 , and will not be described again.

Step S23, the baseband transmitter judges whether it is the first time to determine the pilot signal gain value, if yes, go to step S27; otherwise, continue to step S24;

Step S24, the baseband transmitter further judges whether the currently determined gain value is the same as the last determined gain value, if they are the same, execute step S25; if not, execute step S26

Step S25, the baseband transmitting end still adopts the pilot gain value determined last time as the current pilot gain value, and goes to step S28;

Step S26, update the pilot signal gain value to the currently determined gain value; execute step S27;

Step S27, the baseband transmitting end notifies the receiving end of the determined current pilot signal gain value. The specific notification method may be the same as step S13 in FIG. 3 and will not be described again.

Step S28, the baseband transmitting end multiplies the pilot signal gain value and the pilot sequence to obtain the gained pilot sequence, and sends the gained pilot sequence to the receiving end; the specific implementation method can be the same as step S14 in Figure 3 , without restatement.

Step S29 , after receiving the pilot sequence, the receiving end performs an inverse calculation of the corresponding gain multiple according to the obtained pilot signal gain value, and restores the pilot signal.

If the transmitting end updates the pilot signal gain value, the receiving end is notified through the above step S27; in this step, the receiving end uses the updated pilot signal gain value to perform inverse calculation of the corresponding gain multiple to recover the pilot signal;

If the transmitting end does not update the pilot signal gain value, it is not necessary to notify the receiving end repeatedly; the receiving end uses the previously used pilot signal gain value to perform the inverse calculation of the pilot signal to restore the pilot signal.

Embodiment 2 is mainly applicable to a large range of changes in the linear operating range of the power amplifier (the power amplifier will change greatly according to natural environmental changes such as external temperature and humidity, as well as issues such as aging), or the update of the intermediate frequency clipping threshold higher frequency systems.

In summary, when the present invention transmits pilot signals, a suitable pilot signal gain value is first determined by the baseband transmitter according to the intermediate frequency clipping threshold and the linear operating range of the power amplifier; the determined pilot signal gain The value is multiplied by the pilot sequence to obtain the pilot sequence after gain; the power value of the pilot sequence after gain is satisfied to be less than or equal to the intermediate frequency clipping threshold power value, and less than or equal to the maximum input power value of the linear operating range of the power amplifier. The baseband transmitting end sends the gained pilot sequence to the receiving end, so that the pilot signal transmitted at the baseband transmitting end will not be clipped because it exceeds the intermediate frequency clipping threshold, resulting in distortion; The power amplifier is protected beyond the linear operating range of the power amplifier.

The present invention presets a plurality of optional gain values, multiplies the time-domain power peak value of the pilot sequence by the optional gain values respectively, and obtains a plurality of corresponding gain result values; A gain result value that is closest to the wave threshold power value and is closest to the maximum input power value in the linear range of the power amplifier; the optional gain value corresponding to the determined gain result value is used as the pilot signal gain value. In this way, not only the pilot signal will not be clipped by the intermediate frequency to avoid signal distortion, but also the maximum possible transmission power is used for transmission, which improves the efficiency of the power amplifier and the signal-to-noise ratio of the pilot signal received by the receiving end, making The receiving end can better receive and recover the pilot signal.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (12)

1, a kind of method for controlling emission power of pilot signal is characterized in that, comprising:

A, determine the pilot signal gain value;

B, described pilot signal gain value and pilot frequency sequence are multiplied each other, obtain pilot frequency sequence gained and send.

2, the method for claim 1 is characterized in that, described steps A comprises:

Described base band sending end is determined the pilot signal gain value according to the linear working range of intermediate frequency slicing thresholding and power amplifier; The performance number of pilot frequency sequence gained is satisfied smaller or equal to intermediate frequency slicing threshold power value, and smaller or equal to the maximal input value of power amplifier linearity working range.

3, the method for claim 1 is characterized in that, described steps A comprises:

Described base band sending end continuously or the cycle obtain the linear working range of intermediate frequency slicing thresholding and power amplifier, upgrade the pilot signal gain value of determining; The performance number of pilot frequency sequence gained is satisfied smaller or equal to intermediate frequency slicing threshold power value, and smaller or equal to the maximal input value of power amplifier linearity working range.

4, as claim 2 or 3 described methods, it is characterized in that default a plurality of optional yield values;

Time domain power peak with pilot frequency sequence multiply by described optional yield value respectively, obtains corresponding a plurality of gain results values;

In described a plurality of gain results values, determine with described intermediate frequency slicing threshold power value the most approaching and with the immediate gain results value of power amplifier linearity scope maximal input value;

With the optional yield value of the described gain results value correspondence determined as described pilot signal gain value.

5, the method for claim 1 is characterized in that, also comprise after the described steps A: the described pilot signal gain value that base band sending end will be determined is notified to receiving terminal;

Also comprise after the described step B: receiving terminal carries out the inverse operation of corresponding gain multiple according to described yield value after receiving pilot signal, recovers pilot signal.

6, method as claimed in claim 5 is characterized in that, described base band sending end is notified to receiving terminal with the pilot signal gain value of determining, and concrete grammar is:

Base band sending end sends a pilot signal gain value notification message to receiving terminal, carries the described pilot signal gain value information of determining; After receiving terminal receives this notification message, parse the described pilot signal gain value of carrying; Perhaps

Base band sending end is carried the identification information of expression pilot signal gain value size by existing signaling, and receiving terminal is resolved described identification information, obtains corresponding pilot signal gain value.

7, method as claimed in claim 6 is characterized in that, described identification information is the binary number that takies N bit; After receiving terminal receives this N bit,, determine the yield value of this N bit binary number correspondence according in advance and the corresponding relation of arranging between the base band sending end.

8, method as claimed in claim 7 is characterized in that, the number of bits N that described identification information takies determines according to the yield value number of arranging between base station transmitting terminal and the receiving terminal.

9, method as claimed in claim 5, it is characterized in that, described step B comprises: with base band pilot tone signal directly and the pilot signal gain value multiply each other by multiplier, pilot tone frequency-region signal after obtaining gaining, carry out invert fast fourier transformation IFFT again, pilot tone time-domain signal after obtaining gaining is handled the back by middle Radio frequency Processing Unit, RF Processing Unit and is sent; Perhaps

Base band pilot tone signal is carried out the IFFT conversion earlier, multiply each other by multiplier with described pilot signal gain value after transforming to time domain again, the pilot tone time-domain signal after obtaining gaining is handled the back by middle Radio frequency Processing Unit, RF Processing Unit and is sent,

Receiving terminal carries out fast fourier transform FFT earlier after receiving time-domain pilot signal, obtain the pilot tone signal after, carry out the inverse operation of corresponding gain multiple again, recover pilot signal.

10, the method for claim 1 is characterized in that, also comprises before the described steps A: select the less Serial No. of power peak-to-average force ratio PAPR value as pilot frequency sequence.

11, method as claimed in claim 10 is characterized in that, the less Serial No. of described PAPR value can be generated by the PN sequence generator of 13 bits.

12, the method for claim 1 is characterized in that, for many antenna transmission systems, among the described step B, described base band sending end sends pilot frequency sequence gained to each root antenna; Each antenna carries out sending after the IFFT conversion behind the phase rotation coefficient that on the frequency domain pilot frequency sequence gained be multiply by correspondence again.

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