Embodiment
Below in conjunction with specification drawings and specific embodiments, the utility model will be further described.
As shown in Figure 3, for the structural representation of the utility model for the automatic gain control equipment embodiment of radio-frequency transmitter, this automatic gain control equipment 30 can comprise: RF front-end module 12, radio frequency peak detector 31, intermediate frequency peak detector 32 and automatic gain control module 16, radio frequency peak detector 31 is connected to the input of RF front-end module 12, intermediate frequency peak detector 32 is connected to the output of RF front-end module 12, automatic gain control module 16 respectively with RF front-end module 12, radio frequency peak detector 31 is connected with intermediate frequency peak detector 32.
RF front-end module 12 is for being converted to intermediate-freuqncy signal by radiofrequency signal; Radiofrequency signal is by antenna reception; Radio frequency peak detector 31 is for detection of the range value of radiofrequency signal; Intermediate frequency peak detector 32 is for detection of the range value of intermediate-freuqncy signal; Automatic gain control module 16 is controlled the maximum gain of RF front-end module for the range value according to radiofrequency signal, control the gain of RF front-end module according to the range value of intermediate-freuqncy signal.
In the present embodiment, RF front-end module 12 is converted to intermediate-freuqncy signal by radiofrequency signal, radio frequency peak detector 31 detects the range value of radiofrequency signal, intermediate frequency peak detector 32 detects the range value of intermediate-freuqncy signal, automatic gain control module 16 is controlled the maximum gain of RF front-end module according to the range value of radiofrequency signal, control the gain of RF front-end module according to the range value of intermediate-freuqncy signal, like this, realize that the radio frequency peak value detects and the intermediate frequency peak value detects two kinds of functions simultaneously, control the linear condition of RF front-end module gain according to intermediate frequency peak value testing result, control the maximum of RF front-end module gain according to radio frequency peak value testing result, can realize departing from the far away and radiofrequency signal amplitude of local oscillated signal frequency when larger when radio frequency signal frequency, can make the RF front-end module linear work, the interference that the harmonic wave of elimination radiofrequency signal and the harmonic wave of local oscillated signal cause intermediate-freuqncy signal.
Alternatively, as shown in Figure 4, for first structural representation of the utility model for the automatic gain control module in structural representation shown in automatic gain control equipment embodiment Fig. 3 of radio-frequency transmitter, automatic gain control module 16 can comprise: radio frequency adjustment unit 161 and the first intermediate frequency adjustment unit 162; When radio frequency adjustment unit 161 is less than the radio frequency threshold value for the range value when radiofrequency signal, controlling maximum gain is the first maximum gain; When the range value of radiofrequency signal is greater than the radio frequency threshold value, controlling maximum gain is the second maximum gain, makes the range value of radiofrequency signal equal the radio frequency threshold value; The maximum radio frequency signal amplitude value that the radio frequency threshold value is RF front-end module 12 linear works, the radio frequency threshold value can be 32mV.When the first intermediate frequency adjustment unit 162 is greater than the first intermediate frequency threshold value for the range value when the intermediate frequency signal, the gain of controlling RF front-end module 12 reduces, and makes the range value of intermediate-freuqncy signal equal the first intermediate frequency threshold value.The maximum intermediate-freuqncy signal range value that the first intermediate frequency threshold value is the analog to digital converter linear work, the first intermediate frequency threshold value can be 700mV.
As shown in Figure 5, for the fundamental diagram of the utility model for the automatic gain control module in structural representation shown in automatic gain control equipment embodiment Fig. 4 of radio-frequency transmitter, Vthrf is the radio frequency threshold value, Vthif is the first intermediate frequency threshold value, Gmax is the first maximum gain, Gmax ' is the second maximum gain, Gmax is greater than Gmax ', Gmin is the RF front-end module least gain, radiofrequency signal amplitude when V1 is intermediate-freuqncy signal amplitude arrival intermediate frequency threshold value, radiofrequency signal amplitude when Vmax is RF front-end module arrival least gain, intermediate-freuqncy signal amplitude when V2 is radiofrequency signal amplitude arrival radio frequency threshold value, V2 is less than Vthif, dotted line means that the intermediate-freuqncy signal amplitude changes with the radio frequency signal amplitude, solid line means that the RF front-end module gain changes with the radio frequency signal amplitude.Fig. 5 A is depicted as radio frequency signal frequency and the local oscillated signal frequency phase-difference is nearer, because equaling radio frequency signal frequency, the frequency of intermediate-freuqncy signal deducts the local oscillated signal frequency, so the frequency of intermediate-freuqncy signal is less, intermediate-freuqncy signal can all be passed through low pass filter substantially, amplitude fading is less, now the intermediate-freuqncy signal amplitude first arrives the first intermediate frequency threshold value Vthif, and the radiofrequency signal amplitude does not also arrive radio frequency threshold value Vthrf; When the radiofrequency signal amplitude hour, the RF front-end module gain is Gmax.Along with the increase of radiofrequency signal amplitude, the intermediate-freuqncy signal amplitude is also along with increase, until the radiofrequency signal amplitude is while arriving V1, the intermediate-freuqncy signal amplitude arrives Vthif, and the RF front-end module gain starts to reduce to keep the intermediate-freuqncy signal amplitude to maintain Vthif.When the radiofrequency signal amplitude reaches Vmax, the RF front-end module gain is reduced to Gmin.Fig. 5 B is depicted as radio frequency signal frequency and the local oscillated signal frequency phase-difference is far away, the frequency of intermediate-freuqncy signal is larger, the intermediate-freuqncy signal amplitude is low pass filtering device and decays, now the radiofrequency signal range value first arrives radio frequency threshold value Vthrf, the intermediate-freuqncy signal amplitude is only V2, also not to the first intermediate frequency threshold value Vthif; When the radiofrequency signal amplitude hour, the RF front-end module gain is Gmax.Along with the increase of radiofrequency signal amplitude, the intermediate-freuqncy signal amplitude is also along with increase, but increasing degree is less than the situation shown in Fig. 5 A.Increase along with the radiofrequency signal amplitude, the radiofrequency signal amplitude first arrives radio frequency threshold value Vthrf, the intermediate-freuqncy signal range value does not also arrive the first intermediate frequency threshold value Vthif, now the radiofrequency signal amplitude continues to increase, and just makes the RF front-end module nonlinear operation, and this is not wish situation about occurring, therefore in order to make the RF front-end module linear work, gain that just can only the limitation of radio frequency front-end module is Gmax ', and can not be Gmax, until the radiofrequency signal amplitude is increased to Vmax.Visible, the automatic gain control equipment of radio frequency reception receiver of the present utility model can be realized two kinds of functions of radio frequency peak detector and intermediate frequency peak detector simultaneously, and owing to having increased the radio frequency peak detector and having utilized the RF front-end module gain control method, can effectively eliminate when radio frequency signal frequency and local oscillated signal frequency phase-difference are far away and radiofrequency signal amplitude when larger, the interference that the harmonic wave of radiofrequency signal and the harmonic wave of local oscillated signal cause intermediate-freuqncy signal, make the RF front-end module linear work.
Alternatively, as shown in Figure 6, for second structural representation of the utility model for the automatic gain control module in structural representation shown in automatic gain control equipment embodiment Fig. 3 of radio-frequency transmitter, automatic gain control module 16 can comprise: radio frequency adjustment unit 161, the first intermediate frequency adjustment unit 162 and the second intermediate frequency adjustment unit 163, when radio frequency adjustment unit 161 is less than the radio frequency threshold value for the range value when radiofrequency signal, controlling maximum gain is the first maximum gain; When the range value of radiofrequency signal is greater than the radio frequency threshold value, controlling maximum gain is the second maximum gain, makes the range value of radiofrequency signal equal the radio frequency threshold value; The maximum radio frequency signal amplitude value that the radio frequency threshold value is RF front-end module 12 linear works, the radio frequency threshold value can be 32mV.When the first intermediate frequency adjustment unit 162 is greater than the first intermediate frequency threshold value for the range value when the intermediate frequency signal, the gain of controlling RF front-end module 12 reduces, and makes the range value of intermediate-freuqncy signal equal the first intermediate frequency threshold value; The maximum intermediate-freuqncy signal range value that the first intermediate frequency threshold value is the analog to digital converter linear work, the first intermediate frequency threshold value can be 700mV.When the second intermediate frequency adjustment unit 163 is less than the second intermediate frequency threshold value for the range value when the intermediate frequency signal, the gain of controlling RF front-end module 12 increases.The minimum intermediate-freuqncy signal range value that the second intermediate frequency threshold value is the analog to digital converter linear work, the second intermediate frequency threshold value can be 350mV.
As shown in Figure 7, for the fundamental diagram of the utility model for the automatic gain control module in structural representation shown in automatic gain control equipment embodiment Fig. 6 of radio-frequency transmitter, Vthif1 is the first intermediate frequency threshold value, Vthif2 is the second intermediate frequency threshold value, Ta, Tb can mean arbitrary time point, solid line be the intermediate-freuqncy signal amplitude over time.Now the intermediate frequency peak detector adopts sluggish detection mode, the first intermediate frequency threshold value and the second intermediate frequency threshold value are set, if make the RF front-end module linear work, just need make the amplitude of intermediate-freuqncy signal be positioned at the scope of the first intermediate frequency threshold value and the second intermediate frequency threshold value.When Ta, the intermediate-freuqncy signal amplitude is greater than the first intermediate frequency threshold value, therefore the gain that the first intermediate frequency adjustment unit will be controlled the second variable gain amplifying unit reduces 6dB, thereby makes the intermediate-freuqncy signal amplitude be reduced to just in time in the scope in the first intermediate frequency threshold value and the second intermediate frequency threshold value; While along with the time, arriving Tb, the intermediate-freuqncy signal amplitude is less than the second intermediate frequency threshold value, therefore the gain that the second intermediate frequency adjustment unit will be controlled the second variable gain amplifying unit be take 1dB and is increased gently as unit, until make the intermediate-freuqncy signal amplitude increase to just in time in the scope in the first intermediate frequency threshold value and the second intermediate frequency threshold value.As long as the intermediate-freuqncy signal amplitude, not in the scope of the first intermediate frequency threshold value and the second intermediate frequency threshold value, will be adjusted according to the intermediate frequency detection signal gain of the second variable gain amplifying unit, so that the RF front-end module linear work.Certainly, the radio frequency peak detector also can adopt this kind of sluggish detection mode, does not repeat them here.
Alternatively, then structural representation shown in Figure 3, RF front-end module 12 can comprise: the first variable gain amplifying unit 121, local oscillator 122, frequency mixer 123, low pass filter 124 and the second variable gain amplifying unit 125; The first variable gain amplifying unit 121 is connected with automatic gain control module 16, frequency mixer 123 is connected with local oscillator 122 with the first variable gain amplifying unit 121, low pass filter 124 is connected with frequency mixer 123, and the second variable gain amplifying unit 125 is connected with low pass filter 124 with automatic gain control module 16; The first variable gain amplifying unit 121 is used to radiofrequency signal to carry out the variable gain amplification and processes; Local oscillator 122 is for generating local oscillated signal; Frequency mixer 123 carries out Frequency mixing processing for radiofrequency signal and the local oscillated signal that variable gain is amplified after processing, the output intermediate-freuqncy signal; Low pass filter 124 is for carrying out the filtering processing by intermediate-freuqncy signal; The second variable gain amplifying unit 125 carries out variable gain for the intermediate-freuqncy signal by after processing and amplifies processing; Radio frequency adjustment unit 161 is for controlling the maximum gain of the first variable gain amplifying unit 121, and wherein, when the range value of radiofrequency signal is less than the radio frequency threshold value, the maximum gain of controlling the first variable gain amplifying unit 121 is the first maximum gain; When the range value of radiofrequency signal is greater than the radio frequency threshold value, the maximum gain of controlling the first variable gain amplifying unit 121 is the second maximum gain, makes the range value of radiofrequency signal equal the radio frequency threshold value; The first intermediate frequency adjustment unit 162 is for controlling the gain of the second variable gain amplifying unit 125, wherein, when the range value of intermediate frequency signal is greater than the first intermediate frequency threshold value, the gain of controlling the second variable gain amplifying unit 125 reduces, and makes the range value of intermediate-freuqncy signal equal the first intermediate frequency threshold value.
Alternatively, RF front-end module 12 can comprise: radio frequency adjustment unit 161 is for controlling the maximum gain of the first variable gain amplifying unit 121, wherein, when the range value of radiofrequency signal is less than the radio frequency threshold value, the maximum gain of controlling the first variable gain amplifying unit 121 is the first maximum gain; When the range value of radiofrequency signal is greater than the radio frequency threshold value, the maximum gain of controlling the first variable gain amplifying unit 121 is the second maximum gain, makes the range value of radiofrequency signal equal the radio frequency threshold value; The first intermediate frequency adjustment unit 162 is for controlling the gain of the second variable gain amplifying unit 125, wherein, when the range value of intermediate frequency signal is greater than the first intermediate frequency threshold value, the gain of controlling the second variable gain amplifying unit 125 reduces, and makes the range value of intermediate-freuqncy signal equal the first intermediate frequency threshold value; The second intermediate frequency adjustment unit 163 is for controlling the gain of the second variable gain amplifying unit 125, and wherein, when the range value of intermediate frequency signal is less than the second intermediate frequency threshold value, the gain of controlling the second variable gain amplifying unit 125 increases.
As shown in Figure 8, be the schematic flow sheet of the utility model for the auto gain control method embodiment of radio-frequency transmitter, the method can comprise the steps:
Step 81, RF front-end module are converted to intermediate-freuqncy signal by radiofrequency signal;
Alternatively, radiofrequency signal is by antenna reception.
Step 82, radio frequency peak detector detect the range value of radiofrequency signal;
Step 83, intermediate frequency peak detector detect the range value of intermediate-freuqncy signal;
Step 84, automatic gain control module are controlled the maximum gain of RF front-end module according to the range value of radiofrequency signal, control the gain of RF front-end module according to the range value of intermediate-freuqncy signal.
Alternatively, the automatic gain control module can comprise: radio frequency adjustment unit and the first intermediate frequency adjustment unit, and wherein, when the range value of radiofrequency signal is less than the radio frequency threshold value, it is the first maximum gain that the radio frequency adjustment unit is controlled maximum gain; When the range value of radiofrequency signal is greater than the radio frequency threshold value, it is the second maximum gain that the radio frequency adjustment unit is controlled maximum gain, makes the range value of radiofrequency signal equal the radio frequency threshold value; The maximum radio frequency signal amplitude value that the radio frequency threshold value is the RF front-end module linear work, the radio frequency threshold value can be 32mV.When the range value of intermediate frequency signal is greater than the first intermediate frequency threshold value, the gain that the first intermediate frequency adjustment unit is controlled RF front-end module reduces, and makes the range value of intermediate-freuqncy signal equal the first intermediate frequency threshold value; The maximum intermediate-freuqncy signal range value that the first intermediate frequency threshold value is the analog to digital converter linear work, the first intermediate frequency threshold value can be 700mV.
Alternatively, the automatic gain control module can comprise: radio frequency adjustment unit, the first intermediate frequency adjustment unit and the second intermediate frequency adjustment unit, wherein, when the range value of radiofrequency signal is less than the radio frequency threshold value, it is the first maximum gain that the radio frequency adjustment unit is controlled maximum gain; When the range value of radiofrequency signal is greater than the radio frequency threshold value, it is the second maximum gain that the radio frequency adjustment unit is controlled maximum gain, makes the range value of radiofrequency signal equal the radio frequency threshold value; When the range value of intermediate frequency signal is greater than the first intermediate frequency threshold value, the gain that the first intermediate frequency adjustment unit is controlled RF front-end module reduces, and makes the range value of intermediate-freuqncy signal equal the first intermediate frequency threshold value; When the range value of intermediate frequency signal is less than the second intermediate frequency threshold value, the gain that the second intermediate frequency adjustment unit is controlled RF front-end module increases.The minimum intermediate-freuqncy signal range value that the second intermediate frequency threshold value is the analog to digital converter linear work, the second intermediate frequency threshold value can be 350mV.
In the present embodiment, RF front-end module is converted to intermediate-freuqncy signal by radiofrequency signal, the radio frequency peak detector detects the range value of radiofrequency signal, the intermediate frequency peak detector detects the range value of intermediate-freuqncy signal, the automatic gain control module is controlled the maximum gain of RF front-end module according to the range value of radiofrequency signal, control the gain of RF front-end module according to the range value of intermediate-freuqncy signal.Utilize this method, realize that the radio frequency peak value detects and the intermediate frequency peak value detects two kinds of functions simultaneously, control the linear condition of RF front-end module gain according to intermediate frequency peak value testing result, control the maximum of RF front-end module gain according to radio frequency peak value testing result, can realize departing from the far away and radiofrequency signal amplitude of local oscillated signal frequency when larger when radio frequency signal frequency, can make the RF front-end module linear work, the interference that the harmonic wave of elimination radiofrequency signal and the harmonic wave of local oscillated signal cause intermediate-freuqncy signal.
Alternatively, RF front-end module can comprise: the first variable gain amplifying unit, local oscillator, frequency mixer, low pass filter and the second variable gain amplifying unit, the first variable gain amplifying unit is connected with the automatic gain control module, frequency mixer is connected with local oscillator with the first variable gain amplifying unit, low pass filter is connected with frequency mixer, and the second variable gain amplifying unit is connected with low pass filter with the automatic gain control module; The first variable gain amplifying unit is that radiofrequency signal is carried out variable gain amplification processing; Local oscillator generates local oscillated signal; Radiofrequency signal and local oscillated signal that frequency mixer amplifies variable gain after processing carry out Frequency mixing processing, the output intermediate-freuqncy signal; Low pass filter carries out the filtering processing by intermediate-freuqncy signal; The second variable gain amplifying unit carries out variable gain by the intermediate-freuqncy signal after processing and amplifies processing; The radio frequency adjustment unit is for controlling the maximum gain of the first variable gain amplifying unit, and wherein, when the range value of radiofrequency signal is less than the radio frequency threshold value, the maximum gain of controlling the first variable gain amplifying unit is the first maximum gain; When the range value of radiofrequency signal is greater than the radio frequency threshold value, the maximum gain of controlling the first variable gain amplifying unit is the second maximum gain, makes the range value of radiofrequency signal equal the radio frequency threshold value; The first intermediate frequency adjustment unit is for controlling the gain of the second variable gain amplifying unit, wherein, when the range value of intermediate frequency signal is greater than the first intermediate frequency threshold value, the gain of controlling the second variable gain amplifying unit reduces, and makes the range value of intermediate-freuqncy signal equal the first intermediate frequency threshold value.
Alternatively, the automatic gain control module can comprise: the radio frequency adjustment unit is for controlling the maximum gain of the first variable gain amplifying unit, wherein, when the range value of radiofrequency signal is less than the radio frequency threshold value, the maximum gain of controlling the first variable gain amplifying unit is the first maximum gain; When the range value of radiofrequency signal is greater than the radio frequency threshold value, the maximum gain of controlling the first variable gain amplifying unit is the second maximum gain, makes the range value of radiofrequency signal equal the radio frequency threshold value; The first intermediate frequency adjustment unit is for controlling the gain of the second variable gain amplifying unit, wherein, when the range value of intermediate frequency signal is greater than the first intermediate frequency threshold value, the gain of controlling the second variable gain amplifying unit reduces, and makes the range value of intermediate-freuqncy signal equal the first intermediate frequency threshold value; The second intermediate frequency adjustment unit is for controlling the gain of the second variable gain amplifying unit, and wherein, when the range value of intermediate frequency signal is less than the second intermediate frequency threshold value, the gain of controlling the second variable gain amplifying unit increases.
As shown in Figure 9, structural representation for the utility model radiofrequency receiving chip embodiment, radiofrequency receiving chip 90 can comprise: automatic gain control equipment 30, analog to digital converter 13, digital signal processor 14 and digital to analog converter 15, analog to digital converter 13 is connected with automatic gain control equipment 30, digital signal processor 14 is connected with analog to digital converter 13, and digital to analog converter 15 is connected with digital signal processor 14.Automatic gain control equipment 30 is converted to intermediate-freuqncy signal by radiofrequency signal, detect the range value of radiofrequency signal and the range value of intermediate-freuqncy signal, control the maximum gain of RF front-end module according to the range value of radiofrequency signal, control the gain of RF front-end module according to the range value of intermediate-freuqncy signal; Analog to digital converter 13 is transformed into digital medium-frequency signal by analog if signal; Digital signal processor 14 is demodulated to digital audio and video signals by digital medium-frequency signal, for example: carry out image frequency and suppress processing, frequency-selective filtering processing, demodulation process and audio frequency filtering processing; Digital to analog converter 15 is transformed into simulated audio signal by digital audio and video signals.
Automatic gain control equipment 30 can, for the automatic gain control equipment of the radio-frequency transmitter in previous embodiment, not repeat them here.
As shown in figure 10, be the structural representation of the utility model radio-frequency transmitter embodiment, this radio-frequency transmitter can comprise: antenna 11 and radiofrequency receiving chip 90, radiofrequency receiving chip 90 is connected with antenna 11.
Antenna 11 received RF signals; Radiofrequency receiving chip 90 is processed radiofrequency signal; Radiofrequency receiving chip 90 can, for the radiofrequency receiving chip shown in Fig. 9, not repeat them here.
Finally it should be noted that: above embodiment is only unrestricted in order to the technical solution of the utility model to be described, although with reference to preferred embodiment, the utility model is had been described in detail, those of ordinary skill in the art is to be understood that, can modify or be equal to replacement the technical solution of the utility model, and not break away from the spirit and scope of technical solutions of the utility model.