Balanced sideband separation radio frequency receiving device
By combining components such as RF couplers, power dividers, and mixers, the phase balance problem of balanced sideband split mixer receivers is solved, achieving efficient separation of upper and lower sideband signals and low noise characteristics, thus improving the system's sensitivity and economy.
Patent Information
- Application Number
- CN202423086392.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-13
- Publication Date
- 2025-11-21
- Estimated Expiration
- 2034-12-13
AI Technical Summary
Existing balanced sideband split mixer receivers have difficulty achieving complete phase balance between the RF signal and the local oscillator signal during manufacturing and assembly, resulting in limited image suppression, large system errors, and high component complexity and cost.
The system employs a combination of a first RF 90-degree coupler, a power divider, a second RF 90-degree coupler, a third RF 90-degree coupler, a mixer module, a first magic T, a second magic T, an intermediate frequency 90-degree coupler, and a load. The mixer achieves frequency conversion and phase conversion, while the power divider and coupler achieve power distribution and phase delay, thus separating the upper and lower sideband signals.
It achieves simultaneous detection of upper and lower sideband signals, avoids system errors, has a simple structure, high sensitivity, low equivalent noise temperature, and is easy to debug and optimize while being economical.
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Figure CN223584168U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to astronomical detection instrument field especially is related to a balanced sideband separation radio frequency receiving device. BACKGROUND
[0002] As a key component of radio astronomy telescopes, radio astronomy receiver systems have undergone a process from early performance limitations to gradual improvement. Early receiver systems had deficiencies in noise performance and sensitivity. With the application of low-noise amplifiers and cryogenic mixers, performance has improved, but traditional receiver systems gradually fail to meet the demand for higher observation accuracy and efficiency. In the field of modern communication and detection, the accurate reception and analysis of weak signals in complex electromagnetic environments is also a problem to be solved.
[0003] Balanced sideband separation mixer receivers have many significant advantages. First, they have high sensitivity and extremely low noise temperature, effectively receiving weak signals. For example, in radio astronomy observations, they can detect weak radio signals from more distant celestial bodies, providing more data for astronomical research. Second, the possibility of spectral line overlap is low, and the sideband type of the outgoing signal is fixed, reducing the probability of spectral line overlap. In spectral analysis, the signal spectrum is clearer, avoiding signal confusion and misjudgment caused by spectral line overlap. In millimeter wave band molecular line observations, different molecular line characteristics can be accurately distinguished, helping interstellar molecular research. Third, they have high-precision amplitude calibration capability, maintaining amplitude and phase stability during signal transmission, achieving high-precision amplitude calibration. This is crucial in scenarios that require accurate signal strength measurement, such as radar systems that can improve target detection and recognition accuracy. Fourth, they have good wideband receiving capability, with a wide receiving bandwidth that can adapt to different frequency range signal receiving requirements. In modern communication systems, it can be compatible with multiple communication standards and frequency bands, improving system versatility and adaptability.
[0004] Balanced sideband separation mixer receivers have important applications in multiple fields due to their advantages. In the field of radio astronomy observations, it is a core component of radio telescopes, widely used in galactic molecular cloud research, star formation and evolution observation, interstellar medium physics research, and molecular line sky survey. By receiving and analyzing cosmic weak radio signals, astronomers can gain a deeper understanding of the physical properties and evolution of celestial bodies. In deep space exploration, its high sensitivity and low noise characteristics enable it to effectively receive and process weak signals from distant spacecraft in deep space environments, providing support for spacecraft communication and control. In electronic reconnaissance and intelligence collection, it can be used to intercept and analyze enemy communication signals. Its wideband receiving capability and high-precision signal processing capability enable it to quickly and accurately acquire target signals and analyze and decode them in complex electromagnetic environments, providing support for intelligence collection and decision-making.
[0005] In summary, the balanced sideband separation mixer receiver has important application value, but the balanced sideband separation mixer receiver commonly used at present needs to use many radio frequency couplers, power dividers, mixers and filters and other components, the system complexity and design difficulty are high, and the cost is also high, the complex circuit structure can cause the loss and interference in the signal processing process to increase, and more delicate debugging and optimization are needed. In the balanced sideband separation mixer receiver, the phase balance of the radio frequency coupler and the mixer and other components needs to be ensured to avoid signal distortion and interference. However, due to errors in the manufacturing and assembly process, the phase balance can be difficult to completely achieve, when the frequencies of the radio frequency signal and the local oscillator signal are very close, the image rejection effect can be limited, and the separation observation can bring system errors. Utility model content
[0006] The utility model discloses a balanced sideband separation radio frequency receiving device which overcomes the defects of the prior art and separates upper and lower sideband signals.
[0007] The utility model discloses a balanced sideband separation radio frequency receiving device which overcomes the defects of the prior art and separates upper and lower sideband signals.
[0008] A balanced sideband separation radio frequency receiving device, the device includes first radio frequency 90 degree coupler, power divider, second radio frequency 90 degree coupler, third radio frequency 90 degree coupler, mixing module, first magic T, second magic T, intermediate frequency 90 degree coupler and load, the incident end of first radio frequency 90 degree coupler is connected radio frequency feed and load, the incident end of power divider is connected local oscillator signal source, the incident end of first radio frequency 90 degree coupler and power divider are connected with the input end of second radio frequency 90 degree coupler and third radio frequency 90 degree coupler respectively, the 4 incident ends of second radio frequency 90 degree coupler and third radio frequency 90 degree coupler are connected with the input end of first magic T and second magic T through mixing module, two by two, the incident end of two magic T is connected with intermediate frequency 90 degree coupler, and the output end of intermediate frequency 90 degree coupler includes 0 degree incident end outputting upper sideband signal and 90 degree incident end outputting lower sideband signal.
[0009] Further, the mixing module includes first mixer, second mixer, third mixer and fourth mixer;
[0010] Wherein, the incident end of first mixer and second mixer is connected with the two incident ends of second radio frequency 90 degree coupler respectively, and the incident end of first mixer and second mixer is connected with the incident end of first magic T;
[0011] The incident end of third mixer and fourth mixer is connected with the two incident ends of third radio frequency 90 degree coupler respectively, and the incident end of third mixer and fourth mixer is connected with the incident end of second magic T.
[0012] Further, the first radio frequency 90-degree coupler comprises two output ends outputting signals of same intensity and 90-degree phase difference, and the output ends are connected with the input ends of the second radio frequency 90-degree coupler and the third radio frequency 90-degree coupler respectively.
[0013] Further, the first radio frequency 90-degree coupler comprises two output ends outputting signals of same intensity and 90-degree phase difference, and the output ends are connected with the input ends of the second radio frequency 90-degree coupler and the third radio frequency 90-degree coupler respectively.
[0014] Further, the first radio frequency 90-degree coupler comprises two output ends outputting signals of same intensity and 90-degree phase difference, and the output ends are connected with the input ends of the second radio frequency 90-degree coupler and the third radio frequency 90-degree coupler respectively.
[0015] Further, the first radio frequency 90-degree coupler comprises two output ends outputting signals of same intensity and 90-degree phase difference, and the output ends are connected with the input ends of the second radio frequency 90-degree coupler and the third radio frequency 90-degree coupler respectively.
[0016] Further, the first radio frequency 90-degree coupler comprises two output ends outputting signals of same intensity and 90-degree phase difference, and the output ends are connected with the input ends of the second radio frequency 90-degree coupler and the third radio frequency 90-degree coupler respectively.
[0017] Further, the first radio frequency 90-degree coupler comprises two output ends outputting signals of same intensity and 90-degree phase difference, and the output ends are connected with the input ends of the second radio frequency 90-degree coupler and the third radio frequency 90-degree coupler respectively.
[0018] Further, the first radio frequency 90-degree coupler comprises two output ends outputting signals of same intensity and 90-degree phase difference, and the output ends are connected with the input ends of the second radio frequency 90-degree coupler and the third radio frequency 90-degree coupler respectively.
[0019] Further, the first radio frequency 90-degree coupler comprises two output ends outputting signals of same intensity and 90-degree phase difference, and the output ends are connected with the input ends of the second radio frequency 90-degree coupler and the third radio frequency 90-degree coupler respectively.
[0020] Compared with the prior art, the utility model has the following beneficial effects:
[0021] 1. The utility model discloses a mixer, magic T, power divider, radio frequency 90-degree coupler and intermediate frequency 90-degree coupler are organically combined, the mixer realizes the function of frequency conversion and phase conversion, and the power divider, radio frequency 90-degree coupler and intermediate frequency 90-degree coupler realize the function of power distribution and phase delay, finally realize the separation of upper and lower sideband signals, can realize the simultaneous detection of upper and lower sideband signals, and upper and lower sideband signals are emitted from the fixed port, effectively avoid the system error caused by discrete observation.
[0022] 2. The utility model has the characteristics of simple structure, high sensitivity and small equivalent noise temperature, and relatively simple debugging optimization also guarantees the economy. DRAWINGS
[0023] Figure 1 It is the structural schematic diagram of the utility model;
[0024] Figure 2 It is the application schematic diagram of one embodiment of the utility model. DETAILED DESCRIPTION
[0025] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative work should belong to the protection scope of the utility model.
[0026] A balanced sideband separation radio frequency receiving device, as shown in Figure 1 The device comprises a first radio frequency 90-degree coupler 1, a power divider 2, a second radio frequency 90-degree coupler 3, a third radio frequency 90-degree coupler 4, a mixing module 5, a first magic T 6, a second magic T 7, an intermediate frequency 90-degree coupler 8 and a load 9. Ideally, the image rejection ratio of the balanced sideband separation radio frequency receiving device is ∞.
[0027] In the device, the 0-degree incident end of the first radio frequency 90-degree coupler 1 is connected to a radio frequency feed source, the 90-degree incident end is connected to the load 9, and the output end outputs two-way signals with intensity 1:1 and phase difference 90 degrees. The two-way output ends are respectively connected to the input ends of the second radio frequency 90-degree coupler 3 and the third radio frequency 90-degree coupler 4.
[0028] The incident end of the power divider 2 is connected to a local oscillator signal source, the output end outputs two-way signals with intensity 1:1 and the same phase, and the two-way output ends are respectively connected to the input ends of the second radio frequency 90-degree coupler 3 and the third radio frequency 90-degree coupler 4.
[0029] The first radio frequency 90-degree coupler 1 and the power divider 2 are both connected to the device using a Y-shaped structure.
[0030] When the exit ends of the first radio frequency 90-degree coupler 1 and the power divider 2 are respectively connected to the second radio frequency 90-degree coupler 3 and the third radio frequency 90-degree coupler 4, they are also connected using a Y-shaped structure.
[0031] The four exit ends of the second radio frequency 90-degree coupler 3 and the third radio frequency 90-degree coupler 4 are connected to the input ends of the first magic T 6 and the second magic T 7 through the mixing module 5.
[0032] The mixing module 5 comprises a first mixer 51, a second mixer 52, a third mixer 53 and a fourth mixer 54, and the four mixers are independently biased and output sum frequency and difference frequency respectively.
[0033] The incident ends of the first mixer 51 and the second mixer 52 are respectively connected to the two exit ends of the second radio frequency 90-degree coupler 3, and the exit ends of the first mixer 51 and the second mixer 52 are connected to the incident end of the first magic T 6.
[0034] The input terminals of the third mixer 53 and the fourth mixer 54 are respectively connected to the two output terminals of the third RF 90-degree coupler 4, and the output terminals of the third mixer 53 and the fourth mixer 54 are connected to the input terminal of the second magic T7.
[0035] The two magic T's output terminals are connected to the intermediate frequency 90-degree coupler 8. The 0-degree output terminal of the intermediate frequency 90-degree coupler 8 outputs the upper sideband signal, and the 90-degree output terminal outputs the lower sideband signal.
[0036] In another embodiment, the receiving device is also connected to a digital signal display, the display screen of which outputs a sideband analog signal diagram.
[0037] The following example illustrates the practical application of the balanced sideband split RF receiver in this embodiment.
[0038] like Figure 2 As shown, quadrature hybrid is an orthogonal mixer. The first RF 90-degree coupler 1, the second RF 90-degree coupler 3, the third RF 90-degree coupler 4, and the intermediate frequency 90-degree coupler 8 are all orthogonal mixers. In-phase powerdivider is an in-phase power divider, i.e., power divider 2. Mixer bias+ refers to each mixer in the mixing module 5. The external load simulates the mixing process of the magic T, representing the first magic T6 and the second magic T7. 4K load is the load 9.
[0039] Although both the power divider 2 and the first RF 90-degree coupler 1 use a Y-type connection device to separate the input signal, this will cause a phase difference of π. Therefore, in order to solve this problem, the wires in the figure also use a Y-type structure at the junction of CE and DF, which will also produce a phase difference of π in the opposite direction. That is, when the output terminals of the first RF 90-degree coupler 1 and the power divider 2 are connected to the second RF 90-degree coupler 3 and the third RF 90-degree coupler 4 respectively, a Y-type connection is also used to generate a phase difference of π. The two phase differences just cancel each other out, so the phase difference can be ignored in the calculation.
[0040] Ideally, an RF signal is input to point A, the 90-degree incident end of the first RF 90-degree coupler 1, and an LO signal is input to point B, the input end of the power divider 2.
[0041] The input signal magnitude is as follows:
[0042]
[0043] After being processed by the first 90-degree radio frequency coupler 1, signals C and D are output respectively;
[0044] The signal C and the signal D are as follows:
[0045]
[0046] The B-LO signal is processed by the power divider 2, and the output signals E and F are obtained respectively.
[0047] The signal E and the signal F are as follows:
[0048]
[0049] First, the upper half of the road is analyzed. The signal C and the signal E are input into the second radio frequency 90-degree coupler 3, and the signals G and H are obtained after the second radio frequency 90-degree coupler 3 is processed.
[0050] The signal G and the signal H are as follows:
[0051]
[0052]
[0053] The signal G is then input into the first mixer 51, and the signal K is obtained after processing. The signal H is input into the second mixer 52, and the signal L is obtained after processing.
[0054] The signal K is as follows:
[0055]
[0056] Among them, the signal G will obtain an IF signal after processing, that is, a difference frequency signal, and the specific size is the latter part of the signal K size expression above. IF stands for intermediate frequency, which represents the intermediate frequency. According to the different ω, the IF signal will be different signals. Here, we do not consider the sum frequency signal, but only analyze the difference frequency signal, as follows:
[0057]
[0058] Similarly, according to the analysis steps of the signal K, the analysis result of the difference frequency signal of the signal L is as follows:
[0059] L:
[0060]
[0061] Next, the KL signal is combined and mixed with the external Load in a similar manner to the magic-T, and the signal O is obtained.
[0062] When ω RF >ω LO , that is, when the input signal is the upper sideband:
[0063] The sum signal of the magic-T output is:
[0064]
[0065] The difference signal of the magic-T output is:
[0066]
[0067] When ω RF <ω LO , that is, the input signal is the lower sideband:
[0068] The sum signal of the magic-T output is:
[0069]
[0070] The difference signal of the magic-T output is:
[0071]
[0072]
[0073] Next, the lower half of the case is analyzed. The signal D and the signal F are input into the third radio frequency 90-degree coupler 4, and after being processed by the third radio frequency 90-degree coupler 4, the signal I and the signal J are obtained.
[0074] The sizes of the signal I and the signal J are as follows:
[0075]
[0076] The signal I is then input into the third mixer 53, and after being processed, the signal M is obtained. The signal H is input into the fourth mixer 54, and after being processed, the signal N is obtained.
[0077] After being processed, the signal M will also obtain an IF signal, that is, a difference frequency signal. Here, the sum frequency signal is not considered, and only the difference frequency signal is analyzed, but it will be found that the upper and lower sidebands of the signal M difference frequency signal are the same, and the sizes are as follows:
[0078]
[0079] Similarly, the upper and lower sidebands of the signal N difference frequency signal are also the same, and the sizes are as follows:
[0080]
[0081] Next, the MN signals are combined, and a similar magic-T mixing is performed with the external Load to obtain the signal P.
[0082] When ω RF >ω LOWhen the input signal is the upper sideband:
[0083] The sum signal output by the magic T is:
[0084]
[0085] The difference signal output by the magic T is:
[0086]
[0087] When ω RF <ω LO When the input signal is the lower sideband:
[0088] The sum signal output by the magic T is:
[0089]
[0090] The difference signal output by the magic T is:
[0091]
[0092] Finally, the signal O and the signal P are input into the intermediate frequency 90-degree coupler 8 to obtain the following signals:
[0093] When ω RF >ω LO When the input signal is the upper sideband:
[0094] The upper port of the intermediate frequency 90-degree coupler 8 outputs:
[0095] The lower port of the intermediate frequency 90-degree coupler 8 outputs: 0.
[0096] That is, the upper sideband signal is emitted from the upper port, and the emitted signal strength is The phase is delayed by 90°.
[0097] When ω RF <ω LO When the input signal is the lower sideband:
[0098] The upper port of the intermediate frequency 90-degree coupler 8 outputs: 0
[0099] The lower port of the intermediate frequency 90-degree coupler 8 outputs:
[0100] That is, the lower sideband signal is emitted from the lower port, and the emitted signal strength is The phase sign changes and leads by 180°.
[0101] If the input signal input ports are reversed, the device can still keep the upper port outputting the upper sideband signal and the lower port outputting the lower sideband signal.
[0102] Using the device, the input radio frequency signal can be separated from the local oscillator signal only with simple structure, the upper sideband signal is always output on the upper port of the intermediate frequency 90-degree coupler 8, the lower sideband signal is output on the lower port of the intermediate frequency 90-degree coupler 8, and the separated signals are observed.
[0103] The above merely describes the specific implementation of the present application, but the protection scope of the present application is not limited to this, any skilled person in the art can easily think of various equivalent modifications or replacements within the technical range disclosed by the present application, and these modifications or replacements should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.
Claims
1. A balanced sideband-separated radio frequency receiving device, the device comprising a first RF 90-degree coupler (1), a power divider (2), a second RF 90-degree coupler (3), a third RF 90-degree coupler (4), a mixer module (5), a first magic T (6), a second magic T (7), an intermediate frequency 90-degree coupler (8), and a load (9), characterized in that, The input end of the first RF 90-degree coupler (1) is connected to the RF feed and the load (9), and the input end of the power divider (2) is connected to the local oscillator signal source. The output ends of the first RF 90-degree coupler (1) and the power divider (2) are respectively connected to the input ends of the second RF 90-degree coupler (3) and the third RF 90-degree coupler (4). The four output ends of the second RF 90-degree coupler (3) and the third RF 90-degree coupler (4) are connected to the input ends of the first magic T (6) and the second magic T (7) through the mixer module (5). The output ends of the two magic Ts are connected to the intermediate frequency 90-degree coupler (8). The output end of the intermediate frequency 90-degree coupler (8) includes a 0-degree output end that outputs the upper sideband signal and a 90-degree output end that outputs the lower sideband signal.
2. The balanced sideband-separated radio frequency receiver according to claim 1, characterized in that, The mixing module (5) includes a first mixer (51), a second mixer (52), a third mixer (53) and a fourth mixer (54); The input ends of the first mixer (51) and the second mixer (52) are respectively connected to the two output ends of the second RF 90-degree coupler (3), and the output ends of the first mixer (51) and the second mixer (52) are connected to the input end of the first magic T (6). The input terminals of the third mixer (53) and the fourth mixer (54) are respectively connected to the two output terminals of the third RF 90-degree coupler (4), and the output terminals of the third mixer (53) and the fourth mixer (54) are connected to the input terminal of the second magic T (7).
3. The balanced sideband-separated radio frequency receiver according to claim 1, characterized in that, The first RF 90-degree coupler (1) includes two output terminals that output signals with the same intensity but a 90-degree phase difference. The output terminals are respectively connected to the input terminals of the second RF 90-degree coupler (3) and the third RF 90-degree coupler (4).
4. A balanced sideband-separated radio frequency receiver according to claim 3, characterized in that, The output terminal of the first RF 90-degree coupler (1) is connected to the second RF 90-degree coupler (3) and the third RF 90-degree coupler (4) in a Y-type connection.
5. A balanced sideband-separated radio frequency receiver according to claim 1, characterized in that, The power divider (2) includes two output terminals that output signals with the same strength and phase. The output terminals are respectively connected to the input terminals of the second RF 90-degree coupler (3) and the third RF 90-degree coupler (4).
6. A balanced sideband-separated radio frequency receiver according to claim 5, characterized in that, The output of the power divider (2) is connected to the second RF 90-degree coupler (3) and the third RF 90-degree coupler (4) in a Y-type connection.
7. A balanced sideband-separated radio frequency receiver according to claim 1, characterized in that, The first RF 90-degree coupler (1) includes a 0-degree incident end and a 90-degree incident end. The 0-degree incident end is connected to an RF feed source, and the 90-degree incident end is connected to a load (9).
8. A balanced sideband-separated radio frequency receiver according to claim 1, characterized in that, The load (9) is a resistor.
9. A balanced sideband-separated radio frequency receiver according to claim 1, characterized in that, The receiving device is also connected to a digital signal display.
10. A balanced sideband-separated radio frequency receiver according to claim 9, characterized in that, The digital signal display includes a display screen that outputs a sideband analog signal graph.