JP2004304316A - Transmission power controller and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stably control the transmission power in a transmission power controller by correcting the temperature, frequency, output dynamic range and number of channels, each causing the detection error in a detector itself. <P>SOLUTION: After orthogonal-modulating the transmission base band signals to convert into radio frequencies and separating a part of high frequency signals amplified up to a specified transmission level, a detector 8 detects them to calculate the mean analog power value Pa of the detected signals powers. A digital mean power detector 13 calculates the mean power of the transmission base band signals and a reference power generator 17 generates a reference power value Pr, based on the mean power value of the transmission base band signals and correction values each for correcting the detection error of the detector. A comparator 18 compares the mean analog power value Pa with the reference power value Pr, a coefficient generator 19 generates a coefficient based on the comparison result signal, and adders 20i, 20q add the coefficients to in-phase components and orthogonal components of the transmission base band signals, respectively, thus adjusting the level of the transmission output signal. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a transmission power control apparatus and a control method thereof, and a base station, and a transmission power control apparatus and a control method thereof in a base station transmitter, and more particularly, to a mobile station for code-spreading and multiplexing and transmitting a plurality of user transmission signals. The present invention relates to a transmission power control device and a control method thereof in a base station of a communication system.
[0002]
[Prior art]
As an example of a mobile communication system, there is a system configuration as shown in FIG.
[0003]
In FIG. 19, when communication is performed between an HS (Hand Set: fixed telephone) 201 and an MS 1 (Mobile System: wireless terminal (mobile station)) 207a, user data transmitted from the HS 201 is transmitted from a subscriber line to an ATM switch. Via CN (Core Network: trunk line) 203 via MMS 202, MMS (Mobile Multimedia Switching System: Mobile Multimedia Switching System) 204, RNC (Radio Network Controller: Radio Network Controller) 205, and BTS1 Relay Station : Wireless base station apparatus (base station)) 206a to the MS1 (207a).
[0004]
The HS 201 and the ATM switch 202 are connected by a subscriber line such as an analog line, an ISDN line, or an optical line. Is wirelessly connected.
[0005]
When communication between mobile stations is performed, for example, user data transmitted from MS2 (207b) is wirelessly transmitted to BTS2 (206b) and transmitted to MS1 (207a) via RNC 205 and BTS1 (206a). Is done.
[0006]
A plurality of, for example, 48 BTSs are connected to the RNC 205 constituting the system, and a plurality of, for example, 8 MSs are connected to each BTS.
[0007]
As a conventional technique for performing transmission power control in a CDMA communication scheme, which is one of the communication schemes of the mobile communication system, the detected power of a transmission RF signal matches the reference power using the average power of a transmission baseband signal as reference power. A technique for adjusting the gain is disclosed in patent literature.
[0008]
FIG. 20 shows a configuration example of the transmission power control device of the related art.
[0009]
In FIG. 20, multiplexed signal generation section 351 multiplexes spread signals of each channel by digital processing and outputs a transmission baseband signal.
[0010]
The wireless unit 353 is configured by analog elements such as a DA converter, a quadrature modulator, a frequency converter, and an amplifier, and performs modulation, frequency conversion, high-frequency amplification, and output.
[0011]
Transmitter gain stabilization section 352 uses the average power of the transmission baseband signal as reference power, detects the power of the transmission RF signal output from radio section 353, and adjusts the gain so that the detected power matches the reference power. The gain is adjusted by the adjusting unit 366.
[0012]
The combining units 351i and 351q of the multiplex signal generating unit 351 combine transmission data spread for each control channel and each user (for each channel) for each in-phase component and each orthogonal component, and output a transmission baseband signal.
[0013]
The multipliers 366b-2 and 366b-3 of the amplitude adjustment unit 366b multiply the in-phase component and the quadrature component of the transmission baseband signal by the gain adjustment coefficient a generated by the coefficient generator 366b-1, respectively, and perform the wireless unit 353. To the quadrature modulation section 353a.
[0014]
The quadrature modulation section 353a performs quadrature modulation on the input transmission baseband signal, the frequency conversion section 353b converts the quadrature modulation output signal into a radio frequency, and the amplification section 353c converts the radio frequency converted signal to a required transmission level. Amplify.
[0015]
The demultiplexer 353d demultiplexes a part of the amplified transmission RF signal, the detector 362 receives the demultiplexed output and outputs a voltage corresponding to the transmission power in logarithm, and the integrator 363 outputs the detector output (transmission Power).
[0016]
The AD converter 364 converts the averaged detected power into a digital signal, and the logarithm / antilogarithm conversion unit 365 converts the converted digital signal into an antilog, and outputs the antilog converted signal as a detection power value Pt. I do.
[0017]
On the other hand, the power calculation unit 361a of the reference power generation unit 361 calculates the power P of the transmission baseband signal, the integrator 361b calculates the average power by integrating the power P, and uses the calculated average power as the reference power value Pr. Output.
[0018]
The comparator 366a-1 of the difference average output unit 366a receives the reference power value Pr and the detected power value Pt to compare the magnitudes, and the integrator 366a-2 compares the reference power value Pr and the detected power value Pt based on the comparison result. Are averaged and output.
[0019]
A coefficient generator 366b-1 generates a coefficient a according to the average value of the difference power, and multipliers 366b-2 and 366b-3 multiply the in-phase component and the quadrature component of the transmission baseband signal by the coefficient a. The amplitude value is adjusted, and the gain of the radio unit 353 is controlled.
[0020]
[Patent Document]
JP 2001-217812 A
[0021]
[Problems to be solved by the invention]
In this way, the average power of the transmission baseband signal is used as the reference power, and the gain of the radio unit is adjusted so that the detected power of the transmission RF signal matches the reference power, so that the gain of the radio unit is stabilized by feedback control. can do.
[0022]
However, in the transmission power control method based on the feedback control, the transmission signal captured via a coupler or the like is detected by a detector including an analog element such as a log amplifier, a diode, and a thermistor to detect the power of the transmission signal. For this reason, a detection error of the detector itself is included, which affects securing a stable output level.
[0023]
FIG. 21 shows the relationship between the output voltage and the temperature when the input level of the diode is kept constant. If the voltage does not change with the temperature, the characteristic becomes flat as indicated by a dotted line.
[0024]
However, actually, the output voltage changes depending on the temperature regardless of the constant input level as shown by the solid line, and the difference between the dotted line and the solid line becomes a detection error of the detector.
[0025]
FIG. 22 is a diagram showing an example of a signal level characteristic in the analog section depending on the frequency when the digital section outputs at a certain signal level. The horizontal axis indicates the frequency used in the system, and the vertical axis indicates the signal in the analog section. Indicates the level.
[0026]
When the detector itself has no level deviation due to the frequency characteristic, the signal has a flat characteristic as shown by a dotted line, but the signal level actually changes with the frequency as shown by a solid line.
[0027]
Therefore, for example, when the operating frequency is 2140 MHz, the signal level of the analog section is 20 W / 43 dBm, but when the operating frequency is 2147.5 MHz, it is 10 W / 40 dBm, and a level difference as indicated by an arrow is generated.
[0028]
As described above, although a signal having a constant signal level is input to the detector, a detection error occurs due to the frequency characteristics of the detector itself, and the level difference cannot be correctly detected.
[0029]
FIG. 23 shows the relationship between the dynamic range of the detector input and output voltage.
[0030]
Compared to the ideal line shown by the dotted line, the actual characteristics of the detector shown by the solid line show that the input level and the output voltage change linearly in the region near the middle of the input level, but in the error region outside the linear region. A detection error indicated by the difference between the dotted line and the solid line occurs, and an error occurs in the output voltage with respect to the input level.
[0031]
In the CDMA communication system, a spread modulation technique is used, and the signal itself has randomness. When a signal obtained by multiplexing a plurality of channels (about 16 channels) is input to the detector, the detection is performed. There is little difference between the average power of the detected signal for a certain unit time (a time sufficiently shorter than about 666 μs per slot, for example, one tenth of 666 μs, about 67 μs) and the instantaneous average power.
[0032]
FIGS. 24, 25 and 26 show the relationship between the detector input signal and the output voltage when the channel multiplexing number N is different. The vertical axis is voltage, the horizontal axis is time, and the time width of the random pattern is as described above. The time indicates a time sufficiently shorter than the unit time, and the area indicates the instantaneous average power.
[0033]
FIG. 24 shows the case where N = 1 and FIG. 25 shows the case where the number of multiplexed channels of N = 2 is small. In this case, the output voltage differs due to the difference of the input random pattern, and the instantaneous average power also differs. The average power for a certain unit time, which is indicated by the sum of the areas of the average power, is also affected by the random pattern.
[0034]
FIG. 26 shows the case where the number of multiplexed channels is large, where N = n (n is a certain number or more, for example, 16 channels). Even if a plurality of random patterns are input, the instantaneous average power has little variation and the average power per unit time is small. The power is also substantially constant, and is less affected by the random pattern.
[0035]
That is, when the number of multiplexed channels is small, the detection is affected by the random pattern of each channel to be multiplexed.
[0036]
As described above, in the detector, a detection error occurs due to the temperature characteristics and frequency characteristics of the detector itself, the output dynamic range of the detector, and the number of multiplexed channels.
[0037]
That is, the analog signal output from the detector includes a temperature deviation and a frequency deviation of the detector itself, a detection error due to the output dynamic range of the detector, and a detection error due to the number of multiplexed channels.
[0038]
For this reason, in the conventional transmission power control method, if only the average power value detected by the detector is handled, it is possible to prevent a change in temperature, a change in the frequency used in the system, a change in the transmission signal level, a change in the number of multiplexed channels, and the like. There is a problem that the transmission power cannot be stabilized because the detection error of the detector itself cannot be absorbed.
[0039]
The present invention has been made in view of such a problem, and it is an object of the present invention to provide a transmission power control device and a control method thereof that can stabilize transmission power control with high accuracy by correcting a detection error in a detector. Aim.
[0040]
[Means for Solving the Problems]
(First Configuration) The power of a transmission signal amplified by performing frequency conversion by modulating a transmission baseband signal is detected by a detection unit, and the average power of the transmission signal and the average power of the transmission signal before the frequency conversion are converted to the average power. A transmission power control device that adjusts the power of the transmission signal based on the correction value output unit that outputs a correction value of a detection error generated in the detection unit; and an average power or the frequency of the transmission signal based on the correction value. Correction means for correcting one or both of the average powers of the transmission signal before the conversion is provided.
[0041]
(Second Configuration) A correction value of the correction value output means is a first correction value based on the number of multiplexed channels in a user transmission signal multiplexed by code spreading, and an output dynamic range of the detection means. , A third correction value based on the frequency characteristic of the detection means, and a fourth correction value based on the temperature characteristic of the detection means.
[0042]
(Third Configuration) In addition, the power of a transmission signal amplified by modulating a frequency-converted transmission baseband signal multiplexed by code spreading is detected by a detection unit, and the average power of the transmission signal and the frequency conversion are detected. A transmission power control device that adjusts the transmission signal power based on the average power of the transmission signal before the correction, and outputs a correction value of a detection error generated in the detection unit based on the number of multiplexed channels. Means and correction means for correcting either the average power of the transmission signal or the average power of the transmission signal before the frequency conversion based on the correction value.
[0043]
(Fourth configuration) Further, storage means for storing in advance the number of channels corresponding to the crest factor calculated from the average power and peak power of the transmission signal before the frequency conversion, and the number of channels corresponding to the calculated crest factor And a channel number output means for outputting the read number of channels as the number of multiplexed channels.
[0044]
BEST MODE FOR CARRYING OUT THE INVENTION
(First Embodiment) FIG. 1 shows an embodiment of a transmission power control apparatus according to the present invention, wherein a baseband signal processing section 1 generates a transmission baseband signal by code spreading and multiplexing transmission data.
[0045]
The adders 20i and 20q of the digital signal processing unit 101 add the transmission level adjustment coefficient k to the in-phase component and the quadrature component of the transmission baseband signal, respectively, and the quadrature modulation unit 2 outputs the level-adjusted transmission baseband signal. And performs quadrature modulation to convert the signal into an analog signal.
[0046]
The analog processing unit 102 converts the frequency of the analog-converted signal, amplifies the signal, and outputs the amplified signal via an antenna, and separates and detects a part of the signal output from the antenna. Calculates the average power of the detection signal, converts the average power value into a digital signal, and outputs it as an analog average power value Pa.
[0047]
Further, the digital average power detection unit 13 of the digital signal processing unit 101 calculates the average power value Pd of the transmission baseband signal and inputs the average power value Pd to the reference power generation unit 17.
[0048]
The reference power generation unit 17 receives the channel number information Cd, the frequency information fd from the control unit described later, and a signal obtained by converting the temperature information Td detected by the analog processing unit 102 into a digital signal, and obtains the signal from each of them. A reference power value Pr is calculated from the correction value and the average power value Pd and is input to the comparator 18.
[0049]
The comparator 18 compares the reference power value Pr with the analog average power value Pa, generates a coefficient k corresponding to the comparison result signal, adds the coefficient k to the transmission baseband signal, and adjusts the level of the transmission signal.
[0050]
FIG. 18 shows an example of control information between the RNC and the BTS making up the mobile communication system of FIG.
[0051]
Here, the baseband signal processing unit 1 in FIG. 1 corresponds to the modulation / demodulation unit 206-3 in FIG. 18, and the digital signal processing unit 101 and the analog processing unit 102 in FIG. 1 both correspond to the radio unit 206-6 in FIG. Equivalent to.
[0052]
In FIG. 18, the BTS radio status monitoring unit 205e of the call processing control unit 205a of the RNC 205 monitors the status of the BTS, and the BTS radio status control unit 205d creates channel number information and frequency information based on the monitoring information. The generated information is sent to the call processing operation processing unit 205b as control information.
[0053]
The call processing operation processing unit 205b replaces the control information with the CDMA signal together with the user data from the ATM line, and the ATM conversion unit 205c converts the CDMA signal into the signal of the mobile station and transmits the CDMA signal via the ATM terminal 206-2 of the BTS 206. The data is transmitted to the control unit 206-5.
[0054]
In the first embodiment, the control unit 206-5 notifies the radio unit 206-6, that is, the reference power generation unit 17 of the digital signal processing unit 101 in FIG. 1, of the channel number information and the frequency information as system information.
[0055]
In FIG. 1, a baseband signal processing unit 1 transmits transmission data CH1 (I) + jCH1 (j) obtained by code-spreading a plurality of users (a plurality of channels) formed of data and control signals such as a pilot, a preamble, and a CRC for each user. Q), CH2 (I) + jCH2 (Q),... CHn (I) + jCHn (Q) are multiplexed for each of I and Q components to generate a transmission baseband signal (I + jQ). Multiplexing section 1i for multiplexing in-phase components CH1 (I), CH2 (I),... CHn (I) of transmission data of each user and orthogonal components CH1 (Q), CH2 (Q),. A multiplexing unit 1q for multiplexing (Q) is provided.
[0056]
The digital signal processing unit 101 includes a quadrature modulation unit 2 that inputs I and Q components of a transmission baseband signal and performs quadrature modulation, and a DA converter 3 that converts a quadrature-modulated signal into an analog signal.
[0057]
The analog processing unit 102 uses the signal frequency of the transmitter 4 to convert the output signal frequency of the DA converter 3 to a radio frequency, the amplifier 6 that amplifies and outputs the frequency-converted high-frequency signal, and the amplifier 6 A detector 8 that separates a part of the high-frequency signal output from the multiplexing unit 7 and captures the power of the transmission signal, detects the power of the transmission signal, and integrates the transmission signal power detected by the detector 8 to calculate an average value. The detection unit 9 includes a temperature sensor 14 that detects the temperature of the analog unit.
[0058]
The digital signal processing unit 101 further converts the average power output from the analog average power detection unit 9 into a digital signal and outputs the digital signal as an analog average power value Pa, and converts the value detected by the temperature sensor 14 into an AD converter 15. A temperature information generator 16 for outputting a signal converted to a digital signal as temperature information Td, a digital average power detector 13 for calculating an average power of a transmission baseband signal and outputting the average power as a digital average power value Pd It has.
[0059]
The digital signal processing unit 101 receives a digital average power value Pd, channel number information Cd, frequency information fd, and temperature information Td to generate a reference power value Pr, a reference power generation unit 17, an analog average power value Pa, A comparator 18 which receives the reference power value Pr and compares the magnitudes, a coefficient generator 19 which generates a coefficient k corresponding to the output of the comparator 18, and adds the coefficient k to the in-phase component and the quadrature component of the transmission baseband signal. And adders 20i and 20q for adjusting the level of the transmission output signal.
[0060]
The adders 20i and 20q may be multipliers. In this case, the coefficients in the multiplication are generated by a coefficient generator.
[0061]
Next, the operation of this embodiment will be described.
[0062]
The baseband signal processing unit 1 code-spreads a plurality of users (a plurality of channels) composed of user data and control signals such as a pilot, a preamble, and a CRC for each user.
[0063]
The multiplexing units 1i and 1q multiplex the code-spread transmission data for each of the I and Q components to generate a transmission baseband signal (I + jQ).
[0064]
The transmission baseband signal output from the baseband signal processing unit 1 is added to the I and Q components by the adders 20i and 20q, respectively, and the transmission level adjustment coefficient k, and input to the quadrature modulation unit 2.
[0065]
The quadrature modulator 2 quadrature-modulates the level-adjusted transmission baseband signal, and the DA converter 3 converts the quadrature-modulated output signal into an analog signal.
[0066]
The converted analog signal is converted to a radio frequency used in the system by using the signal frequency of the transmitter 4 in the frequency converter 5, amplified to a predetermined transmission level by the amplifier 6, and output from the antenna.
[0067]
Part of the high-frequency signal output from the amplifier 6 is separated by a duplexer 7 such as a coupler, a capacitor having a coupling constant independent of the signal frequency, or a coupling pattern, and is input to a detector 8.
[0068]
The detector 8 detects the separated transmission signal power with a diode, a log amplifier, or the like, and the analog average power detection unit 9 calculates the average power by integrating the detected signal power. And the analog average power Pa is input to the comparator 18.
[0069]
On the other hand, the digital average power detector 13 calculates the average power of the transmission baseband signal and inputs the average power to the reference power generator 17 as the digital average power value Pd.
[0070]
The channel number information generation unit 11 is located in the control unit of the BTS configuring the system, and inputs the number of multiplexed channels to the reference power generation unit 17 as channel number information Cd.
[0071]
Similarly, the frequency information generation unit 12 located in the control unit of the BTS inputs the frequency used in the system to the reference power generation unit 17 as frequency information fd.
[0072]
The temperature sensor 14 detects the temperature of the analog circuit section, the AD converter 15 converts the value detected by the temperature sensor 14 into a digital signal, and the temperature information generating section 16 converts the detected value converted into a digital signal into the temperature. The information is input to the reference power generation unit 17 as information Td.
[0073]
The reference power generation unit 17 receives the digital average power value Pd, the number-of-channels information Cd, the frequency information fd, and the temperature information Td, and generates a reference power value Pr from these inputs according to a configuration example to be described later. Enter 18.
[0074]
The comparator 18 compares the analog average power value Pa with the reference power value Pr and outputs a signal corresponding to the comparison result. The coefficient generator 19 generates a coefficient k based on the comparison result signal, and At 20i and 20q, the coefficient k is added to the in-phase component and the quadrature component of the transmission baseband signal to adjust the level of the transmission output signal.
[0075]
FIG. 2 shows an example of the configuration of the reference power generation unit 17, and various tables (output level correction table 17b, channel number correction table 17c, frequency correction table) serving as correction value output means for outputting a correction value of a detection error generated in the detector. 17d, a temperature correction table 17e), and an adder 17a for correcting the digital average power value Pd by the correction value.
[0076]
Further, a digital average power value Pd, channel number information Cd, frequency information fd, and temperature information Td are input.
[0077]
The output level correction table 17b calculates and outputs an output level correction value Pt based on the digital average power value Pd with reference to a table in which correction values are set as shown in FIG. 3, for example.
[0078]
The channel number correction table 17c outputs a channel number correction value Ct obtained by referring to a table in which correction values are set as shown in FIG. 4, for example, based on the channel number information Cd.
[0079]
Similarly, the frequency correction table 17d outputs a frequency correction value ft obtained by referring to the table as shown in FIG. 5 based on the frequency information fd, and the temperature correction table 17e outputs the frequency correction value ft shown in FIG. The temperature correction value Tt obtained by referring to the table shown in FIG.
[0080]
The adder 17a calculates a reference power Pr from the digital average power value Pd and the obtained correction values by the following equation (1).
[0081]
Pr = Pd + Pt + Ct + ft + Tt (1)
FIG. 7 shows an embodiment of the comparator 18 and the coefficient generator 19.
[0082]
The comparator 18 compares the analog average power value Pa with the reference power value Pr, and outputs a down signal “1” if Pa ≧ Pr, and outputs an up signal “0” if Pa <Pr and outputs a coefficient “0”. Input to generator 19.
[0083]
The coefficient generator 19 generates a coefficient k for lowering the transmission level when detecting the down signal "1" and a coefficient k for raising the transmission level when detecting the up signal "0", and inputs the coefficient to the adders 20i and 20q. I do.
[0084]
In FIG. 7, the output signal of the comparator 18 is a 1-bit comparison result signal. However, the difference between Pa and Pr is calculated, the difference is input to a coefficient generator 19, and a coefficient k corresponding to the difference is calculated. It may be generated.
[0085]
Next, the transmission power control device of the present invention will be described using the specific values in FIG. 8 as an example.
[0086]
The same parts as those in FIG. 1 are denoted by the same reference numerals.
[0087]
In FIG. 8, for example, the analog average power value Pa is set to +41.3 (dBm).
[0088]
Further, for example, assuming that the digital average power value Pd is +40 (dBm), an output level correction value Pt = 0.0 (dB) is obtained with reference to the output level correction table of FIG.
[0089]
Further, for example, when the channel number information Cd = 1 (channel), the channel number correction value is Ct = + 2.0 (dB) with reference to the channel number correction table of FIG.
[0090]
Similarly, if the frequency information fd = 2140 (MHz), for example, the frequency correction value ft = + 1.0 (dB) and the temperature information Td = 50 (° C.) with reference to the frequency correction table of FIG. The temperature correction value Tt = −0.2 (dB) is obtained with reference to the temperature correction table.
[0091]
Next, the adder calculates the reference power value Pr = + 42.8 dBm by the equation (1) and inputs the calculated reference power value Pr to the comparator 18.
[0092]
The comparator 18 compares the analog average power value Pa = + 41.3 dBm with the reference power value Pr = + 42.8 dBm and outputs an up signal or a down signal. In this case, since Pa <Pr, the up signal is “0”. Is output to the coefficient generator 19.
[0093]
The coefficient generator 19 detects the up signal "0" and generates a coefficient k for raising the transmission level, for example, k = + 0.2, and the adders 20i and 20q generate the coefficient k for the I and Q components of the transmission baseband signal, respectively. Is added.
[0094]
The adjustment of the transmission level by the coefficient k may be, for example, about 1/10 of about 666 μs per slot, about every 67 μs.
[0095]
As described above, it is possible to stabilize transmission power control with high accuracy by correcting and canceling the detection error of the detector due to the temperature characteristics and frequency characteristics of the detector itself, the output dynamic range of the detector, and the number of multiplexed channels. it can.
[0096]
(Second Embodiment) FIG. 9 shows another embodiment of the transmission power control apparatus according to the present invention, and the same parts as those in the first embodiment of FIG.
[0097]
The difference is that the coefficient generator 19, the adders 20i and 20q for adding the coefficient k generated by the coefficient generator 19 to the transmission baseband signal are eliminated, and before conversion into an analog signal corresponding to the output of the comparator 18. A coefficient generator 31 for generating the coefficient ka of the above, a DA converter 32 for converting the coefficient ka to an analog signal, and a variable attenuation for adjusting the level of the quadrature modulated output signal converted to the analog signal by the coefficient ka converted to the analog signal. A device 33 is provided.
[0098]
In the first embodiment, the level of the transmission output signal is controlled by adding the coefficient k generated by the coefficient generator 19 to the in-phase component I and the quadrature component Q of the transmission baseband signal of the digital signal processing unit 101.
[0099]
In the second embodiment, the coefficient generator 31 generates a coefficient ka for adjusting the variable attenuator 33 based on the comparison result signal from the comparator 18, and the coefficient ka is converted into an analog signal by the DA converter 32. The quadrature modulation output signal converted to an analog signal by the variable attenuator 33 is adjusted by the coefficient ka converted to the analog signal to control the level of the transmission signal.
[0100]
Note that the variable attenuator 33 may be a variable amplifier.
[0101]
As described above, since the coefficient generated based on the comparison result is fed back to the analog section, the configuration can be made without considering the processing time and circuit scale of the digital section, and the number of digital circuit sections can be reduced.
[0102]
(Third Embodiment) FIG. 10 shows another embodiment of the transmission power control apparatus according to the present invention, in which the same parts as those in the first embodiment of FIG.
[0103]
The difference is that the digital signal processing unit 101 is provided with a channel number detection / generation unit 41 without the channel number information generation unit 11.
[0104]
In the first embodiment, the number of multiplexed channels is output from the channel number information generation unit 11 to the reference power generation unit 17 as the channel number information Cd.
[0105]
In the third embodiment, since the crest factor, which is the ratio between the average power and the peak power, and the number of multiplexed channels are in a proportional relationship, the crest factor is calculated in the channel number detection / generation unit 41 and the number of channels is obtained by referring to the table. , Is output as channel number information Cd.
[0106]
FIG. 11 shows an embodiment of the channel number detection / generation unit 41, and the same parts as those in the first embodiment of FIG.
[0107]
The digital average power detector 13 calculates an average power by integrating the calculated power of the transmission baseband signal, a power calculator 13a that calculates the power of the transmission baseband signal, and calculates the average power by the digital average power. An average power calculator 13b that outputs the value as a value Pd is provided.
[0108]
The channel number detection / generation section 41 detects a peak power from the power of the transmission baseband signal output from the power calculation section 13a, a peak power detection section 41a, and the peak power and the average power output from the average power calculation section 13b. A crest factor calculating unit 41b that calculates a crest factor from the crest factor based on the crest factor, for example, referring to a table in which the crest factor and the number of channels are set as shown in FIG. A channel number detection table 41c that outputs the number as channel number information Cd is provided.
[0109]
The peak power detector 41a detects the peak power of the transmission baseband signal from the output of the power calculator 13a, and the crest factor calculator 41b calculates the crest factor from the peak power and the average power obtained by the average power calculator 13b. .
[0110]
The channel number detection table 41c refers to the table based on the crest factor to determine the number of channels, and inputs the determined number of channels to the reference power generation unit 17 as channel number information Cd.
[0111]
As described above, the number of channels can be detected from the transmission signal without providing the channel number information as system information from the control unit, so that the number of control signals can be reduced.
[0112]
(Fourth Embodiment) FIG. 13 shows another embodiment of the transmission power control apparatus according to the present invention, and the same parts as those in the first embodiment of FIG.
[0113]
The difference is that the temperature sensor 14, the AD converter 15, and the temperature information generator 16 are eliminated, and that the temperature information Td input from the temperature information generator 51 is provided.
[0114]
In the first embodiment, the value detected by the temperature sensor 14 of the analog processing unit 102 is converted into a digital signal by an AD converter and output as temperature information Td.
[0115]
In the fourth embodiment, a value detected by the temperature sensor 206-1 located at the BTS in FIG. 18 is notified to the control unit 206-5 via the monitoring unit 206-4, and the detected value is controlled as temperature information. The signal is output from the unit 206-5 to the wireless unit 206-6.
[0116]
That is, in FIG. 13, the value detected by the temperature sensor of the BTS is output from the temperature information generation unit 51 located in the control unit to the reference power generation unit 17 as the temperature information Td.
[0117]
As described above, since the temperature information is received as system information from the control unit, the number of analog circuits related to temperature detection can be reduced.
[0118]
(Fifth Embodiment) FIG. 14 shows another embodiment of the transmission power control apparatus according to the present invention, in which the same parts as those in the first embodiment of FIG.
[0119]
The difference is that the reference power generation unit 17 and the comparator 18 are eliminated, and the comparison power generation P1 that generates the comparison power value P1 from the analog average power value Pa and various information (channel number information Cd, frequency information fd, and temperature information Td). And a comparator 61 for comparing the comparison power value P1 with the digital average power value Pd.
[0120]
In the first embodiment, the reference power generation unit 17 generates a reference power value Pr from the digital average power value Pd, the channel number information Cd, the frequency information fd, and the temperature information Td. The magnitude of the power value Pa was compared.
[0121]
In the fifth embodiment, a comparison power value P1 is generated from the analog average power value Pa and the various types of information, and the comparison power value P1 is compared with the digital average power value Pd.
[0122]
FIG. 15 shows an example of the configuration of the comparison power generation unit 61. Various tables (a channel number correction table 17c, a frequency correction table 17d, a temperature correction table 17e) serving as correction value output means for outputting a correction value of a detection error generated in a detector. ), An adder 61a for correcting the analog average power value Pa with the correction value.
[0123]
Each correction value (Ct, ft, Tt) based on the channel number information Cd, the frequency information fd, and the temperature information Td is obtained by the same processing as in the configuration example of FIG.
[0124]
The adder 61a, unlike the adder 17a of FIG. 2, calculates the comparison power P1 from the analog average power Pa and the respective correction values obtained by the following equation (2).
[0125]
P1 = Pa- (Ct + ft + Tt) (2)
FIG. 16 shows an example of the configuration of the comparator 62. The output level correction table 17b is a correction value output unit that outputs a correction value of a detection error generated in the detector. The digital average power value Pd is corrected by the correction value. An adder 62a and a comparison circuit 62b are provided.
[0126]
The output level correction table 17b receives the digital average power value Pd, obtains an output level correction value Pt by the same processing as in FIG. 2, and outputs it to the adder 62b.
[0127]
The adder 62 corrects the digital average power value Pd by adding the output level correction value Pt and the digital average power value Pd.
[0128]
The comparison circuit 62b compares the corrected digital average power value P2 with the comparison power value P1, and outputs a down signal “1” if P1 ≧ P2, and outputs an up signal “0” if P1 <P2. Output.
[0129]
Although the output signal of the comparator 62 is a one-bit comparison result signal in FIG. 16, a difference between P1 and P2 may be calculated, and the difference may be output as a comparison result signal.
[0130]
As described above, the transmission power control can be stabilized with high accuracy by correcting and canceling the detection error of the detector.
[0131]
(Sixth Embodiment) FIG. 17 shows another embodiment of the transmission power control apparatus according to the present invention, in which the same parts as those of the first embodiment in FIG.
[0132]
In this embodiment, the feedback control is performed by the analog unit.
[0133]
Therefore, in the digital signal processing unit 101, the digital average power detection unit 13, the temperature information generation unit 16, the reference power generation unit 17, the comparator 18, the coefficient generator 19, the adders 20i and 20q, and the AD converters 10 and 15 are used. DA converters 71 and 72 for converting channel number information Cd and frequency information fd into analog signals Ca and fa, respectively.
[0134]
The analog processing unit 102 also includes a detector 77 that separates a part of the analog-converted quadrature modulated signal to detect power, and an average power detection unit that calculates an average power value Pda of the detected signal power in the detector 77. 78, a temperature information generating unit 73 that outputs an analog signal of a value detected by the temperature sensor 14 as temperature information Ta.
[0135]
Further, a reference power generation unit 74 that receives the average power value Pda, the channel number information Ca converted into an analog signal, the frequency information fa also converted into an analog signal, and the temperature information Ta to generate a reference power value Pra, A comparator 75 that receives the average power value Pa1 and the reference power value Pra to compare the magnitudes, a coefficient generator 76 that generates a coefficient ka corresponding to the output of the comparator, and a quadrature modulated signal converted into an analog signal by the coefficient ka. Is provided with a variable attenuator 79 for adjusting the level of.
[0136]
A part of the quadrature modulated signal converted into an analog signal is split by a splitter (not shown) and detected by a detector 77, and an average power detection unit 78 calculates an average power value Pda of the detection signal. .
[0137]
The reference power generation unit 74 and the comparator 75 perform the same operation as in the first embodiment to output a comparison result signal, and the coefficient generator 76 adjusts the variable attenuator 79 based on the comparison result signal. Occurs.
[0138]
However, in the first embodiment, the processing by the digital signal is performed, but in the present embodiment, the processing by the analog signal is performed.
[0139]
The variable attenuator 79 adjusts the level of the quadrature-modulated output signal converted into an analog signal using the coefficient ka.
[0140]
As described above, the circuit of the digital section can be reduced, and the control of the transmission power can be stabilized with high accuracy by correcting the detection error of the detector.
[0141]
In the present invention, in any of the embodiments, the detection error due to the frequency characteristic, temperature characteristic, output dynamic range, and channel multiplexing number of the detector itself is corrected, but at least one of these detection errors is corrected. May be configured so as to correct the error.
[0142]
The main inventions disclosed in the present specification are summarized below.
[0143]
(Supplementary Note 1) The power of the transmission signal, which has been modulated by performing frequency conversion on the transmission baseband signal and amplified, is detected by a detection unit, and based on the average power of the transmission signal and the average power of the transmission signal before the frequency conversion. A transmission power control device that adjusts the power of the transmission signal by
A correction value output unit that outputs a correction value of a detection error generated in the detection unit, and either one of an average power of the transmission signal or an average power of the transmission signal before the frequency conversion based on the correction value, or Correction means for correcting both,
A transmission power control device comprising: (Claim 1)
(Supplementary Note 2) The correction value of the correction value output means is:
A first correction value based on the number of multiplexed channels in a user transmission signal multiplexed by code spreading;
A second correction value based on an output dynamic range of the detection means,
A third correction value based on the frequency characteristic of the detection means,
A fourth correction value based on a temperature characteristic of the detection means,
2. The transmission power control device according to claim 1, comprising at least one of the following.
(Claim 2)
(Supplementary Note 3) The power of the amplified transmission signal is modulated and frequency-converted by modulating the code-spread and multiplexed transmission baseband signal, and the power of the amplified transmission signal is detected by the detection means. In a transmission power control device that adjusts the transmission signal power based on the average power of the transmission signal,
A correction value output unit that outputs a correction value of a detection error generated in the detection unit based on the number of multiplexed channels,
Correction means for correcting one of the average power of the transmission signal or the average power of the transmission signal before the frequency conversion based on the correction value,
A transmission power control device comprising: (Claim 3)
(Supplementary Note 4) Storage means for storing in advance the number of channels corresponding to the crest factor calculated from the average power and peak power of the transmission signal before the frequency conversion,
A channel number output unit that reads the number of channels according to the calculated crest factor from the storage unit, and outputs the read channel number as the multiplexed channel number;
4. The transmission power control device according to claim 3, comprising: (Claim 4)
(Supplementary Note 5) A step of detecting the power of the amplified transmission signal by performing frequency conversion by modulating the transmission baseband signal, and calculating the average power of the transmission signal and the average power of the transmission signal before the frequency conversion. In the transmission power control method for adjusting the power of the transmission signal based on the
Outputting a correction value of a detection error generated in the detecting step;
Correcting either one of the average power of the transmission signal or the average power of the transmission signal before the frequency conversion based on the correction value, or both,
A transmission power control method comprising:
[0144]
(Supplementary Note 6) The correction value is:
A first correction value based on the number of multiplexed channels in a user transmission signal multiplexed by code spreading;
A second correction value based on the output dynamic range of the detecting step;
A third correction value based on the frequency characteristic of the detecting step;
A fourth correction value based on the temperature characteristic of the detecting step;
6. The transmission power control method according to claim 5, comprising at least one of the following.
[0145]
(Supplementary Note 7) A step of modulating a code-spread and multiplexed transmission baseband signal, performing frequency conversion and detecting power of the amplified transmission signal, and performing the frequency conversion with the average power of the transmission signal. In a transmission power control method of adjusting the transmission signal power based on the average power of the previous transmission signal,
Outputting a correction value of a detection error generated in the detecting step based on the number of multiplexed channels,
Correcting either the average power of the transmission signal or the average power of the transmission signal before the frequency conversion based on the correction value,
A transmission power control method comprising:
[0146]
(Supplementary Note 8) a step of storing in advance the number of channels corresponding to the crest factor calculated from the average power and the peak power of the transmission signal before the frequency conversion,
A channel number output step of reading from the storing the channel number according to the calculated crest factor, and outputting the read channel number as the multiplexed channel number;
8. The transmission power control method according to claim 7, further comprising:
[0147]
【The invention's effect】
According to the present invention, it is possible to correct a detection error in the detector, so that control of transmission power can be stabilized with high accuracy.
[0148]
In addition, since correction can be performed based on the number of channels, temperature, frequency, and output level of the detector, it is possible to correct the detection error of the detector itself caused by the number of channels, temperature, frequency, and output dynamic range. it can.
[0149]
Further, since the number of channels can be detected from the transmission signal without providing the number-of-channels information from the control unit, the number of control signals can be reduced.
[Brief description of the drawings]
FIG. 1 is a diagram showing a first embodiment of the present invention.
FIG. 2 is a diagram illustrating a configuration example of a reference power generation unit according to the present invention.
FIG. 3 is a diagram showing an example of an output level correction table according to the present invention.
FIG. 4 is a diagram showing an example of a channel number correction table according to the present invention.
FIG. 5 is a diagram showing an example of a frequency correction table according to the present invention.
FIG. 6 is a diagram showing an example of a temperature correction table according to the present invention.
FIG. 7 is a diagram showing an embodiment of a comparator (1) and a coefficient generator according to the present invention.
FIG. 8 is a diagram showing an example using specific values of the first embodiment of the present invention.
FIG. 9 is a diagram showing a second embodiment of the present invention.
FIG. 10 is a diagram showing a third embodiment of the present invention.
FIG. 11 is a diagram showing an embodiment of a channel number detection / generation unit of the present invention.
FIG. 12 is a diagram showing an example of a channel number detection table based on a crest factor according to the present invention.
FIG. 13 is a diagram showing a fourth embodiment of the present invention.
FIG. 14 is a diagram showing a fifth embodiment of the present invention.
FIG. 15 is a diagram illustrating a configuration example of a comparative power generation unit according to the present invention.
FIG. 16 is a diagram showing a configuration example of a comparator (2) of the present invention.
FIG. 17 is a diagram showing a sixth embodiment of the present invention.
FIG. 18 is a diagram illustrating an example of control information between an RNC and a BTS.
FIG. 19 is a diagram illustrating an example of a mobile communication system.
FIG. 20 is a diagram illustrating a configuration example of a transmission power control device according to the related art.
FIG. 21 is a diagram showing a relationship between an output voltage of a diode and a temperature.
FIG. 22 is a diagram illustrating an example of a signal level characteristic in an analog unit depending on a frequency.
FIG. 23 is a diagram showing the relationship between the dynamic range of the detector input and output voltage.
FIG. 24 is a diagram illustrating an example of a detector input and output voltage when N = 1.
FIG. 25 is a diagram illustrating an example of a detector input and output voltage when N = 2.
FIG. 26 is a diagram illustrating an example of a detector input and output voltage when N = n.
[Explanation of symbols]
1 Baseband signal processing unit
1i, 1q multiplexer
2 Quadrature modulator
3, 32, 71, 72 DA converter
4 transmitter
5 Frequency converter
6 Amplifier
7 Demultiplexer
8,77 detector
9 Analog average power detector
10, 15 AD converter
11 Channel number information generator
12 Frequency information generator
13 Digital average power detector
13a Power calculation unit
13b Average power calculation unit
14 Temperature sensor
16, 51, 73 Temperature information generation unit
17, 74 Reference power generation unit
17a, 61a Adder
17b Output level correction table
17c Channel number correction table
17d frequency correction table
17e Temperature correction table
18, 62, 75 comparator
19, 31, 76 coefficient generator
20i, 20q, 62a Adder
33, 79 Variable attenuator
41 Channel number detection / generation unit
41a Peak power detector
41b Crest factor calculator
41c Channel number detection table
61 Comparison power generation unit
62b comparison circuit
78 Average power detector
101 Digital signal processing unit
102 Analog processing unit
201 Landline (HS: Hand Set)
202 ATM switch
203 Backbone line (CN: Core Network)
204 Mobile Multimedia Switching System (MMS)
205 Radio Network Controller (RNC: Radio Network Controller)
205a call processing control unit
205b Call processing operation processing unit
205c ATM conversion
205d BTS radio state control unit
205e BTS wireless status monitoring unit
206, 206a, 206b, 206c Radio base station apparatus (base station) (BTS: Base Transceiver Station)
206-1 Temperature sensor
206-2 ATM Termination
206-3 Modulator / Demodulator
206-4 Monitoring Unit
206-5 Control Unit
206-6 Radio Unit
207a, 207b Wireless terminal (mobile station) (MS: Mobile System)
351 Multiplex signal generator
351i, 351q Synthesis unit
352 Transmitter gain stabilization unit
353 Radio section
353a Quadrature modulator
353b Frequency conversion unit
353c amplifier
353d duplexer
361 Reference power generation unit
361a Power calculation unit
361b, 363, 366a-2 Integrator
362 detector
364 AD converter
365 log / antilog conversion unit
366 Gain adjustment unit
366a Difference average output unit
366a-1 Comparator
366b Amplitude adjuster
366b-1 Coefficient generator
366b-2, 366b-3 Multiplier

Claims (4)

The power of the transmission signal amplified by performing frequency conversion by modulating the transmission baseband signal is detected by a detection unit, and the transmission signal is detected based on the average power of the transmission signal and the average power of the transmission signal before the frequency conversion. In a transmission power control device that adjusts the power of
Correction value output means for outputting a correction value of a detection error generated in the detection means,
Correction means for correcting either one of the average power of the transmission signal or the average power of the transmission signal before the frequency conversion based on the correction value, or both,
A transmission power control device comprising: The correction value of the correction value output means is:
A first correction value based on the number of multiplexed channels in a user transmission signal multiplexed by code spreading;
A second correction value based on an output dynamic range of the detection means,
A third correction value based on the frequency characteristic of the detection means,
A fourth correction value based on a temperature characteristic of the detection means,
The transmission power control device according to claim 1, comprising at least one of the following. The power of the transmission signal amplified by performing frequency conversion by modulating the code-spread and multiplexed transmission baseband signal is detected by a detection unit, and the average power of the transmission signal and the transmission signal before the frequency conversion are performed. In a transmission power control device that adjusts transmission signal power based on average power,
A correction value output unit that outputs a correction value of a detection error generated in the detection unit based on the number of multiplexed channels,
Correction means for correcting one of the average power of the transmission signal or the average power of the transmission signal before the frequency conversion based on the correction value,
A transmission power control device comprising: Storage means for storing in advance the number of channels corresponding to the crest factor calculated from the average power and peak power of the transmission signal before the frequency conversion,
A channel number output unit that reads the number of channels according to the calculated crest factor from the storage unit, and outputs the read channel number as the multiplexed channel number;
The transmission power control device according to claim 3, comprising:

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