Broadband radio frequency front-end assembly

Abstract

The utility model discloses a broadband radio frequency front-end assembly, which comprises a frequency conversion module, a signal transmitting module and a signal receiving module, the frequency conversion module comprises a superheterodyne primary frequency conversion circuit and a superheterodyne secondary frequency conversion circuit; the superheterodyne primary frequency conversion circuit is connected with the signal sending module; the superheterodyne secondary frequency conversion circuit is connected with the signal receiving module; a duplexer DPX is arranged between the signal sending module and the signal receiving module. By arranging the superheterodyne primary frequency conversion circuit and the superheterodyne secondary frequency conversion circuit, primary frequency conversion is carried out firstly to shift an input signal to a higher high and intermediate frequency, a local oscillator of target signal band frequency conversion falls outside a working frequency band, then the high and intermediate frequency is shifted to a target signal band through secondary frequency conversion, the signal distortion degree is reduced, and the signal quality is improved. And the requirements of bandwidth and sideband suppression can be met at the same time.

Description

Technical Field

[0001] The utility model relates to the technical field of radio frequency signals, in particular to a broadband radio frequency front-end component. Background Art

[0002] When the RF front end performs frequency conversion between broadband IF signals and target signal bands, the transceiver usually uses zero IF and digital IF for frequency conversion processing. Since the zero IF receiver has most of its gain in the zero-frequency baseband circuit, the local oscillator signal leaks into the RF link and is reflected back to the I / Q demodulator. The DC component generated by self-mixing with the local oscillator signal will enter the baseband signal, deteriorating the signal-to-noise ratio of the received signal, increasing the bit error rate, and even causing the baseband amplifier to saturate, thus seriously affecting the receiver performance. When using a zero IF transceiver structure, if the signal amplitude and phase of the I / Q two-way are unbalanced, the baseband I / Q signal will be mismatched, causing the sideband suppression and carrier suppression to deteriorate, and then the EVM will be deteriorated. Since the receiver IF is relatively high, the ADC and DAC are required to have a higher sampling rate. In order to adapt to the fading of the received signal, the ADC is required to have a larger dynamic range. In addition, in order to adapt to the IF signal amplitude, the ADC should have a higher resolution and less noise. Therefore, the digital IF transceiver has higher requirements for ADC and DAC, resulting in an increase in the cost of the transceiver. When the ADC samples the intermediate frequency signal directly, the corresponding anti-aliasing filter is difficult to adapt to the requirements of multi-band and multi-standard, which makes the selection of digital intermediate frequency more difficult. The signal jitter caused by a very high ADC sampling frequency will deteriorate the signal-to-noise ratio and lead to performance degradation. Utility Model Content

[0003] The technical problem to be solved by the utility model is that the use of zero intermediate frequency and digital intermediate frequency for frequency conversion processing is prone to signal distortion, and it is impossible to simultaneously meet the requirements of bandwidth and sideband suppression. The utility model aims to provide a broadband radio frequency front-end component. By setting a superheterodyne primary frequency conversion circuit and a superheterodyne secondary frequency conversion circuit, a primary frequency conversion is first performed to move the input signal to a higher high intermediate frequency, and the local oscillator of the target signal band frequency conversion falls outside the working frequency band. Then, the high intermediate frequency is moved to the target signal band through secondary frequency conversion, thereby reducing the signal distortion and being able to simultaneously meet the requirements of bandwidth and sideband suppression.

[0004] The utility model is realized by the following technical solutions:

[0005] A broadband radio frequency front-end component comprises a frequency conversion module, a signal transmission module and a signal receiving module;

[0006] The frequency conversion module includes a superheterodyne primary frequency conversion circuit and a superheterodyne secondary frequency conversion circuit;

[0007] The superheterodyne primary frequency conversion circuit is connected to the signal sending module;

[0008] The superheterodyne secondary frequency conversion circuit is connected to the signal receiving module;

[0009] A duplexer DPX is arranged between the signal sending module and the signal receiving module.

[0010] The utility model arranges a superheterodyne primary frequency conversion circuit and a superheterodyne secondary frequency conversion circuit, firstly performs a primary frequency conversion to move the input signal to a higher high intermediate frequency, and drops the local oscillator of the target signal band frequency conversion outside the working frequency band, and then moves the high intermediate frequency to the target signal band through secondary frequency conversion, thereby reducing signal distortion and being able to meet the requirements of bandwidth and sideband suppression at the same time.

[0011] Furthermore, the superheterodyne primary frequency conversion circuit includes a low-pass filter F1, a digitally controlled attenuator D1, a mixer M1, a band-pass filter F2, and a power amplifier A1 which are connected in sequence.

[0012] Furthermore, the superheterodyne secondary frequency conversion circuit specifically includes a bandpass filter F3, a low noise amplifier A2, a mixer M2, a low pass filter F4, a power amplifier A3, a digitally controlled attenuator D2 and a power amplifier A4 which are connected in sequence.

[0013] Furthermore, the mixer M1 and the mixer M2 are both connected to a local oscillator LC.

[0014] Furthermore, a power amplifier A5 is provided between the local oscillator LC and the mixer M1, and a power amplifier A6 is provided between the local oscillator LC and the mixer M2.

[0015] Further, the signal transmission module includes a bridge BR1, a bridge BR2, a mixer M3, a mixer M4, a driving amplifier A7 and a power amplifier A8;

[0016] The bridge BR1, mixer M3, bridge BR2 and mixer M4 are connected in sequence to form a connected loop;

[0017] One end of the driving amplifier A5 is connected to the mixer M3 and the mixer M4, and the other end is connected to the power amplifier A8.

[0018] Further, the signal receiving module includes a low noise amplifier A9, a power amplifier A10, a bridge BR3, a bridge BR4, a mixer M5, a mixer M6, a band pass filter F5, and an intermediate frequency amplifier A11;

[0019] The bridge BR3, mixer M5, bridge BR4 and mixer M6 are connected in sequence to form a connected loop;

[0020] One end of the power amplifier P2 is connected to the mixer M5 and the mixer M6, and the other end is connected to the low noise amplifier A9;

[0021] The bridge BR4 is also connected to the bandpass filter F5 and the intermediate frequency amplifier A11 in sequence.

[0022] Furthermore, the bridge BR1 is connected to a frequency multiplier FM1, and the bridge BR3 is connected to a frequency multiplier FM2.

[0023] Furthermore, the bridge BR1, the bridge BR2, the bridge BR3 and the bridge BR4 are all three decibel 90° bridges.

[0024] Furthermore, the mixer M3, the mixer M4, the mixer M5 and the mixer M6 are all image rejection mixers.

[0025] Compared with the prior art, the utility model has the following advantages and beneficial effects:

[0026] By setting up a superheterodyne primary frequency conversion circuit and a superheterodyne secondary frequency conversion circuit, a primary frequency conversion is first performed to move the input signal to a higher high-IF frequency, so that the local oscillator of the target signal band conversion falls outside the working frequency band, and then the high-IF is moved to the target signal band through secondary frequency conversion, thereby reducing signal distortion and meeting the requirements of bandwidth and sideband suppression at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the embodiments of the present utility model, constitute a part of this application, and do not constitute a limitation of the embodiments of the present utility model. In the drawings:

[0028] Figure 1 It is a circuit diagram in an embodiment of the utility model. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the utility model more clearly understood, the utility model is further described in detail below in conjunction with embodiments and drawings. The schematic implementation manner of the utility model and its description are only used to explain the utility model and are not intended to limit the utility model.

[0030] like Figure 1 As shown, a broadband radio frequency front-end component of this embodiment includes a frequency conversion module, a signal sending module and a signal receiving module;

[0031] The frequency conversion module includes a superheterodyne primary frequency conversion circuit and a superheterodyne secondary frequency conversion circuit;

[0032] The superheterodyne primary frequency conversion circuit is connected to the signal sending module;

[0033] The superheterodyne secondary frequency conversion circuit is connected to the signal receiving module;

[0034] A duplexer DPX is arranged between the signal sending module and the signal receiving module.

[0035] This embodiment sets a superheterodyne primary frequency conversion circuit and a superheterodyne secondary frequency conversion circuit, first performs a primary frequency conversion to move the input signal to a higher high-intermediate frequency, and moves the local oscillator of the target signal band frequency conversion outside the working frequency band, and then uses a secondary frequency conversion to move the high-intermediate frequency to the target signal band, thereby reducing signal distortion and meeting the requirements of bandwidth and sideband suppression at the same time.

[0036] In some possible embodiments, the superheterodyne primary frequency conversion circuit includes a low-pass filter F1, a digitally controlled attenuator D1, a mixer M1, a band-pass filter F2, and a power amplifier A1 which are connected in sequence.

[0037] The input signal passes through the low-pass filter F1 and enters the digitally controlled attenuator, and then is mixed with the local oscillator to output the high-IF signal and the image frequency signal. The image frequency signal, local oscillator leakage, intermediate frequency leakage and other high-order combined frequencies are then filtered out by the band-pass filter F2. Finally, the high-IF signal is output through the power amplifier A1 and sent to the signal sending module.

[0038] In some possible embodiments, the superheterodyne secondary frequency conversion circuit specifically includes a bandpass filter F3, a low noise amplifier A2, a mixer M2, a low pass filter F4, a power amplifier A3, a digitally controlled attenuator D2 and a power amplifier A4 which are connected in sequence.

[0039] The input signal in the receiving signal receiving module first passes through the bandpass filter F3 to further filter out the out-of-band spurious and interference signals from the output of the receiving signal receiving module, and then is amplified by the low-noise amplifier A2, mixed with the local oscillator, and outputs the intermediate frequency signal. It passes through the low-pass filter F4 to filter out the local oscillator leakage, high intermediate frequency leakage and other combined frequencies, and then is amplified and output by the digitally controlled attenuator D2 and the power amplifier A3.

[0040] In some possible embodiments, the mixer M1 and the mixer M2 are both connected to a local oscillator LC, a power amplifier A5 is arranged between the local oscillator LC and the mixer M1, and a power amplifier A6 is arranged between the local oscillator LC and the mixer M2. The local oscillator is first split and then amplified in order to increase the isolation of the local oscillator port in the frequency conversion circuit to prevent the transmitting intermediate frequency from leaking to the receiving intermediate frequency and causing interference between transmission and reception.

[0041] In some possible embodiments, the signal sending module includes a bridge BR1, a bridge BR2, a mixer M3, a mixer M4, a driving amplifier A7 and a power amplifier A8; the bridge BR1, the mixer M3, the bridge BR2 and the mixer M4 are connected in sequence to form a connecting loop; one end of the driving amplifier A5 is connected to the mixer M3 and the mixer M4, and the other end is connected to the power amplifier A8.

[0042] In some possible embodiments, the signal receiving module includes a low noise amplifier A9, a power amplifier A10, a bridge BR3, a bridge BR4, a mixer M5, a mixer M6, a band pass filter F5, and an intermediate frequency amplifier A11;

[0043] The bridge BR3, the mixer M5, the bridge BR4 and the mixer M6 are connected in sequence to form a connected loop;

[0044] One end of the power amplifier P2 is connected to the mixer M5 and the mixer M6, and the other end is connected to the low noise amplifier A9;

[0045] The bridge BR4 is also connected in sequence to the bandpass filter F5 and the intermediate frequency amplifier A11.

[0046] In some possible embodiments, bridge BR1 is connected to frequency multiplier FM1, bridge BR3 is connected to frequency multiplier FM2, and the frequency multiplier FM has a multiple of at least six times. Bridge BR1, bridge BR2, bridge BR3 and bridge BR4 all use three-decibels 90° bridges. Mixer M3, mixer M4, mixer M5 and mixer M6 all use image rejection mixers.

[0047] The signal transmission module is a superheterodyne single-conversion structure. The mixer does not use a double-balanced mixer or harmonic mixing. Mixers M3 and M4 use mirror suppression mixing (IRM) to suppress the secondary sideband, eliminating the filter of the mixer output, which improves the RF output spurious suppression to a certain extent and reduces the design difficulty. The local oscillator signal is input from the outside, and mixer M3 integrates a 6-multiplier FM. The signal transmission module suppresses the secondary sideband by inputting the high-frequency signal through mirror suppression mixing, then amplifies it through the driver amplifier, and finally outputs it through the power amplifier.

[0048] The signal receiving module uses the same superheterodyne frequency conversion structure as the signal sending module. The mixer of the signal receiving module also uses the image suppression mixing (IRM) method. The advantage of this is that the image suppression filter between the low noise amplifier and the mixer is omitted, which reduces the design difficulty. The local oscillator signal is input from the outside, and the mixer integrates a 6-frequency multiplier FM.

[0049] The input RF signal is firstly amplified by low noise amplifier A9, then input into mixer M5 to suppress the secondary sideband and then mixed to output high intermediate frequency signal, and then filtered out by bandpass filter F5 to remove local oscillator leakage, combined spurious signal and out-of-band interference signal, and then amplified by high intermediate frequency to output.

[0050] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the utility model in detail. It should be understood that the above description is only the specific implementation method of the utility model and is not used to limit the protection scope of the utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. A broadband radio frequency front-end component, characterized in that: It includes a frequency conversion module, a signal sending module and a signal receiving module; The frequency conversion module includes a superheterodyne primary frequency conversion circuit and a superheterodyne secondary frequency conversion circuit; The superheterodyne primary frequency conversion circuit is connected to the signal sending module; The superheterodyne secondary frequency conversion circuit is connected to the signal receiving module; A duplexer DPX is arranged between the signal sending module and the signal receiving module.

2. A broadband RF front-end component according to claim 1, characterized in that: The superheterodyne primary frequency conversion circuit comprises a low-pass filter F1, a digitally controlled attenuator D1, a mixer M1, a band-pass filter F2, and a power amplifier A1 which are connected in sequence.

3. A broadband RF front-end component according to claim 2, characterized in that: The superheterodyne secondary frequency conversion circuit specifically includes a bandpass filter F3, a low noise amplifier A2, a mixer M2, a low pass filter F4, a power amplifier A3, a digitally controlled attenuator D2 and a power amplifier A4 which are connected in sequence.

4. A broadband RF front-end component according to claim 3, characterized in that: The mixer M1 and the mixer M2 are both connected to a local oscillator LC.

5. A broadband radio frequency front-end component according to claim 4, characterized in that: A power amplifier A5 is provided between the local oscillator LC and the mixer M1, and a power amplifier A6 is provided between the local oscillator LC and the mixer M2.

6. A broadband radio frequency front-end component according to claim 1, characterized in that: The signal transmission module includes a bridge BR1, a bridge BR2, a mixer M3, a mixer M4, a driving amplifier A7 and a power amplifier A8; The bridge BR1, mixer M3, bridge BR2 and mixer M4 are connected in sequence to form a connected loop; One end of the driving amplifier A5 is connected to the mixer M3 and the mixer M4, and the other end is connected to the power amplifier A8.

7. A broadband radio frequency front-end component according to claim 6, characterized in that: The signal receiving module includes a low noise amplifier A9, a power amplifier A10, a bridge BR3, a bridge BR4, a mixer M5, a mixer M6, a band pass filter F5, and an intermediate frequency amplifier A11; The bridge BR3, mixer M5, bridge BR4 and mixer M6 are connected in sequence to form a connected loop; One end of the power amplifier P2 is connected to the mixer M5 and the mixer M6, and the other end is connected to the low noise amplifier A9; The bridge BR4 is also connected to the bandpass filter F5 and the intermediate frequency amplifier A11 in sequence.

8. A broadband radio frequency front-end component according to claim 7, characterized in that: The bridge BR1 is connected to a frequency multiplier FM1, and the bridge BR3 is connected to a frequency multiplier FM2.

9. A broadband radio frequency front-end component according to claim 7, characterized in that: The bridges BR1, BR2, BR3 and BR4 all adopt three-decibel 90° bridges.

10. The broadband radio frequency front-end component according to claim 7, characterized in that: The mixer M3, the mixer M4, the mixer M5 and the mixer M6 are all image rejection mixers.

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