High-frequency low-insertion-loss strong-suppression waveguide filter

Abstract

The invention discloses a high-frequency low-insertion-loss strong-suppression waveguide filter which comprises an I / O port, an electric coupling window, a square groove window and a zero point window, and far-end harmonic waves of the filter are optimal by adjusting the height of a resonant cavity. According to the high-frequency low-insertion-loss strong-suppression waveguide filter, the high integration level is achieved through the low-temperature co-fired ceramic (LTCC) three-dimensional integration technology, and the high-frequency low-insertion-loss strong-suppression waveguide filter can be applied to 7GHz communication.

Description

Technical Field

[0001] The invention relates to a high-frequency, low-insertion-loss, strong-suppression waveguide filter. Background Art

[0002] A filter is a frequency-selective device that allows specific frequency components in a signal to pass through while greatly attenuating other frequency components. The frequency-selective function of the filter can be used to filter out interference noise or perform spectrum analysis. In other words, any device or system that allows specific frequency components in a signal to pass through while greatly attenuating or suppressing other frequency components is called a filter.

[0003] With the development of communication technology, the performance requirements for filters are getting higher and higher. It is necessary to design a high-frequency, low-insertion-loss, strong-suppression waveguide filter that can be used for 7GHz communication. Summary of the invention

[0004] In order to solve the defects of the prior art, the present invention provides a high-frequency, low-insertion-loss, strong-suppression waveguide filter, including an I / O port, an electrical coupling window, a square slot window, and a zero-point window, and the far-end harmonics of the filter are optimized by adjusting the height of the resonant cavity.

[0005] Preferably, the I / O port is connected to the head and tail resonant cavities of the filter to enhance port coupling.

[0006] Preferably, the I / O port has an annular air window.

[0007] Preferably, the annular air window is used to adjust the port coupling amount.

[0008] Preferably, the electrically coupled window has four cavities at the front and rear, each forming a CQ structure, generating two pairs of left and right notch points to enhance near-edge suppression.

[0009] Preferably, the upper semi-annular window and the lower semi-annular window of the electrical coupling window are used to adjust the strength of the electrical coupling.

[0010] Preferably, the square slot windows are a pair, which are used to adjust two pairs of zero point balances.

[0011] Preferably, the zero point windows are a pair for adjusting the strength of the zero point.

[0012] The advantages and beneficial effects of the present invention are: providing a high-frequency, low-insertion-loss, strong-suppression waveguide filter that achieves high integration through low-temperature co-fired ceramic (LTCC) three-dimensional integration technology and can be applied to 7GHz communication.

[0013] The present invention also has the following characteristics: 1. The present invention adopts microwave low-loss dielectric ceramics, a dielectric constant of 5.0-10.0, and a dielectric loss of less than 0.001. After adding a certain proportion of adhesive, dispersant and solvent, a green ceramic material is formed through a casting process.

[0014] 2. The present invention adopts a multi-layer structure which is laminated together, cut and sintered into porcelain, and finally made into a product.

[0015] 3. The bandpass filter of the present invention adopts an integrated resonant cavity structure design, which is convenient for subsequent debugging and production.

[0016] 4. The height of the resonant cavity in the structure of the present invention is much smaller than that of the traditional dielectric waveguide, so that the resonant frequency of the filter is much greater than 2 times the frequency.

[0017] 5. The insertion loss of the filter in the passband of the present invention is less than 2.5dB.

[0018] 6. The far-end double frequency suppression of the filter of the present invention is greater than 60dB. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the high-frequency, low-insertion-loss, strong-suppression waveguide filter of the present invention; Figure 2 It is the S curve of a single BPF. DETAILED DESCRIPTION

[0020] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0021] The technical solutions specifically implemented in the present invention are as follows: like Figure 1 As shown, the present invention provides a high-frequency, low-insertion-loss, strong-suppression waveguide filter, including an I / O port, an electrical coupling window, a square slot window, and a zero-point window; 1 and 2 are filter I / O ports, which are connected to the head and tail resonant cavities of the filter to enhance port coupling; the I / O port has an annular air window to adjust the port coupling amount; 3 and 4 are the electric coupling windows of the filter, with 4 cavities at the head and tail, each forming a CQ structure, generating two pairs of left and right notch points to enhance near-edge suppression; the upper semi-circular window and the lower semi-circular window of the electric coupling window are used to adjust the strength of the electric coupling (to avoid difficulties in debugging due to deep holes); 5 and 6 are square slot windows, used to adjust two pairs of zero balance; 7 and 8 are zero point windows, used to adjust the zero point strength; 9 is the height of the filter resonant cavity, and the far-end harmonics of the filter are optimized by adjusting the height of the resonant cavity.

[0022] like Figure 2 It is the S curve of a single BPF.

[0023] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A high-frequency, low insertion loss, strong suppression waveguide filter, characterized in that: It includes an I / O port, an electric coupling window, a square slot window, and a zero point window, and the far-end harmonics of the filter are optimized by adjusting the height of the resonant cavity.

2. The high-frequency, low insertion loss, strong suppression waveguide filter according to claim 1, characterized in that: The I / O port is connected to the head and tail resonant cavities of the filter to strengthen port coupling.

3. The high-frequency, low insertion loss, strong suppression waveguide filter according to claim 2, characterized in that: The I / O port has an annular air window.

4. The high-frequency, low insertion loss, strong suppression waveguide filter according to claim 3, characterized in that: The annular air window is used to adjust the port coupling amount.

5. The high-frequency, low insertion loss, strong suppression waveguide filter according to claim 1, characterized in that: The electric coupling window has four cavities at the front and rear, each forming a CQ structure, generating two pairs of left and right notch points to enhance near-edge suppression.

6. The high-frequency, low insertion loss, strong suppression waveguide filter according to claim 5, characterized in that: The upper semi-circular window and the lower semi-circular window of the electric coupling window are used to adjust the strength of the electric coupling.

7. The high-frequency, low insertion loss, strong suppression waveguide filter according to claim 1, characterized in that: The square slot windows are a pair and are used to adjust two pairs of zero point balances.

8. The high-frequency, low insertion loss, strong suppression waveguide filter according to claim 1, characterized in that: The zero point windows are a pair and are used to adjust the strength of the zero point.

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