CN1992516A - Band-pass filter - Google Patents
Band-pass filter Download PDFInfo
- Publication number
- CN1992516A CN1992516A CN 200510121391 CN200510121391A CN1992516A CN 1992516 A CN1992516 A CN 1992516A CN 200510121391 CN200510121391 CN 200510121391 CN 200510121391 A CN200510121391 A CN 200510121391A CN 1992516 A CN1992516 A CN 1992516A
- Authority
- CN
- China
- Prior art keywords
- coupling part
- pass filter
- resonator
- band pass
- feed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Control Of Motors That Do Not Use Commutators (AREA)
Abstract
It is a band-pass filter, placed in a substrate, and the said band-pass filter includes an input, an output, a first coupling unit, a second coupling unit and a resonator. The input is used to feed in electromagnetic signals, and the output is used to feed out electromagnetic signals. The first coupling unit electrical connects with the input, and the second coupling unit electrical connects with the output, parallel placed with the first coupling unit. The resonator is parallel placed between the first coupling unit and the second coupling unit, and the resonator includes a groove. As the implementation of the invention, due to the band-pass filter having resonator with a groove, and using the capacitive feed-in and capacitive feed-out, it can not only reduce its occupied area, but also has good filtering function.
Description
[technical field]
The present invention relates to a kind of high frequency assembly, relate in particular to a kind of filter.
[background technology]
In recent years, because the market demand of mobile communication product heightens, make that the development of radio communication is more rapid, in numerous wireless communication standards, the most noticeable is that U.S.'s Institute of Electrical and Electronics Engineers is (hereinafter to be referred as IEEE) 802.11 WLAN of Zhi Dinging (Wireless Local AreaNetwork) agreement.This agreement was formulated in 1997, and it not only provides many unprecedented functions on the radio communication, and the solution that provides the wireless communications products that can make various different brands to be communicated with each other.The formulation of this agreement has been opened a new milestone for the radio communication development undoubtedly.IEEE 802.11b/g is current standard commonly used in many standards that IEEE formulated, and its working frequency range is 2.45GHz.
Filter is the indispensable high frequency assembly in the mobile communication product simultaneously, and its major function is to be used for crossover frequency,, blocks the signal of other frequencies by the signal of some frequencies that is.Desirable filter characteristic should be that the passband frequency range is undamped and infinitely great in decay in frequency range, and the saltus step of passband and cut-off frequency should be precipitous as much as possible.In the radio-frequency module (RadioFrequency Module) of IEEE 802.11b/g product, the part assembly still has generation or receives the unnecessary signal ability of (being called noise) in the both sides of nearby pass (2.45GHz).This noise easily produces many negative effects to communication products.Outside for product, can produce problem as electromagnetic interference (EMI), for product inside, then can cause the signal quality of emission/reception not good, therefore the performance of product is greatly affected.In present design, normally strengthen the filter function of filter, yet when increasing resonator, also can increase the shared area of filter by the quantity that increases resonator.
In addition, because many wireless communications products all develop towards light, thin, short, little direction, so need be under the prerequisite of the performance of taking into account filter simultaneously the shared area of filter be reduced.
[summary of the invention]
For solving the deficiency that above-mentioned prior art exists, the technical issues that need to address are to reduce the shared area of filter under the prerequisite that does not influence performance of filter.
A kind of band pass filter is arranged on the substrate, and described band pass filter comprises an input, an output, one first coupling part, one second coupling part, and a resonator.Input is used for the feed-in electromagnetic wave signal, and output is used to feed out electromagnetic wave signal.First coupling part is electrically connected at input, and second coupling part is electrically connected at output, and is arranged side by side with first coupling part.Resonator is parallel to be arranged between first coupling part and second coupling part, and resonator comprises a groove.
Band pass filter in the embodiment of the present invention has the resonator of groove owing to have one, and adopts condenser type feed-in and condenser type to feed out, and not only can reduce its shared area, also has filter function preferably simultaneously.
[description of drawings]
Fig. 1 is the schematic diagram of band pass filter in the embodiment of the present invention.
Fig. 2 is the resolution chart of band pass filter in electromagnetical analogies gained embodiment of the present invention.
[embodiment]
See also Fig. 1, be depicted as the schematic diagram of band pass filter 10 in the embodiment of the present invention.
In the present embodiment, band pass filter 10 is arranged on the substrate 20, and it comprises an input 100, an output 120, one first coupling part 140, one second coupling part 160 and a resonator 180.
Input 100 is used for the feed-in electromagnetic wave signal, and output 120 is used to feed out electromagnetic wave signal.Input 100 roughly is positioned at same straight line with output 120, and input 100 and output 120 are 50 ohm of matched impedances of band pass filter 10.So the filter 10 in the present embodiment does not need to increase extra electric capacity or resistance is made matched impedance, to reach the purpose of the volume that dwindles filter 10.
First coupling part 140 is electrically connected at input 100, the second coupling parts 160 and is electrically connected at output 120, and is arranged side by side with first coupling part 140.
Resonator 180 comprises a groove 1800, and resonator 180 parallel being arranged between first coupling part 140 and second coupling part 160.In the present embodiment, resonator 180 and groove 1800 all are square, and groove 1800 is arranged at the approximate centre position of resonator 180.Resonator 180 comprises one the 3rd coupling part 1820, one the 4th coupling part 1840, one the 5th coupling part 1860 and one the 6th coupling part 1880.
The 3rd coupling part 1820 all equates with the length and the width of the 4th coupling part 1840, and is parallel to each other.The 5th coupling part 1860 all equates with the length and the width of the 6th coupling part 1880, and is parallel to each other.The 5th coupling part 1860 is vertically connected at an end of the 3rd coupling part 1820 and the 4th coupling part 1840, and the 6th coupling part 1880 is vertically connected at the other end of the 3rd coupling part 1820 and the 4th coupling part 1840.That is, the 3rd coupling part 1820, the 4th coupling part 1840, the 5th coupling part 1860 and the 6th coupling part 1880 are connected to each other the square trench 1800 of common formation resonator 180.
Resonator 180 can be coupled by the 3rd coupling part 1820 and the 4th coupling part 1840.The 3rd coupling part 1820, the 4th coupling part 1840, the 5th coupling part 1860 and the 6th coupling part 1880 are connected to each other and form resonance.
First coupling part 140 and the 3rd coupling part 1820 form a feed-in electric capacity, with the electromagnetic wave signal feed-in resonator 180 that will transmit from input 100.Second coupling part 160 and the 4th coupling part 1840 form one and feed out electric capacity, so that electromagnetic wave signal is fed out to output 120 from resonator 180.The selection of the load point of resonator 180 should guarantee that the shortest feed-in path of electromagnetic wave signal is about 1/4th of resonator 180 girths, comes across near the frequency range of center with the transmission zero of control filters 180.Simultaneously, the size of adjusting feed-in electric capacity and feeding out electric capacity is to guarantee that filter 180 has filter function preferably in the passband frequency range.
See also Fig. 2, be depicted as the resolution chart of band pass filter 10 in electromagnetical analogies gained embodiment of the present invention.Among the figure transverse axis represent by the signal of band pass filter in the embodiment of the present invention 10 frequency (unit: GHz), the longitudinal axis represent the gain (unit: dB), the quadrant district comprises the scattering parameter (S-parameter:S of transmission
21) gain and the reflection scattering parameter (S-parameter:S
11) gain.Scattering parameter (the S of transmission
21) expression by the signal of band pass filter 10 in the one embodiment of the present invention input power and the relation between the power output of signal, its corresponding mathematical function is expressed as:
Power output/input power (dB)=20 * Log|S
21|.
The signal of band pass filter 10 is in transmission course in embodiment of the present invention, and the part power of signal is reflected back toward signal source.The power that is reflected back toward signal source is called reflection power.Be expressed as by the signal gain of band pass filter in the embodiment of the present invention 10 and the mathematical function relationship formula between input power and the reflection power:
Reflection power/incident power (dB)=20 * Log|S
11|.
As shown in Figure 2, band pass filter 10 has good band pass filter performance in the embodiment of the present invention.From curve | S
21| can be observed, form the insertion loss of steeper " transition slope " and the signal in passband frequency range near 0 between passband frequency range and decay frequency range.Simultaneously from curve | S
11| can be observed, the signal reflex loss absolute value in the passband frequency range is greater than 10, and outside the passband frequency range, then signal reflex loss absolute value is less than 10.In addition, in the embodiment of the present invention there be the first zero A and the second zero point B except producing near passband frequency range (2.45GHz) band pass filter 10, also subsidiary produce have one the 3rd zero point C, can more effectively suppress the outer noise of passband frequency range, with the filter function of enhancement band filter 10.
Band pass filter 10 in the embodiment of the present invention is owing to have the resonator 180 of a with groove 1800, and condenser type feed-in and condenser type feed out, not only can reduce the shared volume of band pass filter 10, also can make band pass filter 10 have filter function preferably simultaneously.
Claims (11)
1. a band pass filter is arranged on the substrate, it is characterized in that described band pass filter comprises:
One input is used for the feed-in electromagnetic wave signal;
One output is used to feed out electromagnetic wave signal;
One first coupling part is electrically connected at described input;
One second coupling part is arranged side by side with described first coupling part, and is electrically connected at described output; And
One resonator, parallel being arranged between described first coupling part and described second coupling part, described resonator comprises a groove.
2. band pass filter as claimed in claim 1 is characterized in that described input and described output are 50 ohm of matched impedances.
3. band pass filter as claimed in claim 1 is characterized in that described input and described output roughly are positioned at same straight line.
4. band pass filter as claimed in claim 1, it is square to it is characterized in that described resonator and described groove are, and described groove is arranged at the approximate centre position of described resonator.
5. band pass filter as claimed in claim 4 is characterized in that described resonator comprises one the 3rd coupling part and one the 4th coupling part, and described the 3rd coupling part all equates with described the 4th coupling part length and width, and is parallel to each other.
6. band pass filter as claimed in claim 5 is characterized in that described resonator can be coupled by described the 3rd coupling part and described the 4th coupling part.
7. band pass filter as claimed in claim 5 is characterized in that described first coupling part and described the 3rd coupling part form a feed-in electric capacity, with the described resonator of electromagnetic wave signal feed-in that will transmit from described input.
8. band pass filter as claimed in claim 5 is characterized in that described second coupling part and described the 4th coupling part form one and feed out electric capacity, so that electromagnetic wave signal is fed out to described output from described resonator.
9. band pass filter as claimed in claim 5, it is characterized in that described resonator more comprises one the 5th coupling part and one the 6th coupling part, described the 5th coupling part all equates with described the 6th coupling part length and width, and be parallel to each other, and described the 3rd coupling part, described the 4th coupling part, described the 5th coupling part and described the 6th coupling part are connected to each other the groove that constitutes described resonator.
10. band pass filter as claimed in claim 9 is characterized in that described the 3rd coupling part, described the 4th coupling part, described the 5th coupling part and described the 6th coupling part are connected to each other formation resonance.
11. band pass filter as claimed in claim 1 is characterized in that the shortest feed-in path of described resonator is about 1/4th of described resonator girth.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510121391 CN1992516A (en) | 2005-12-28 | 2005-12-28 | Band-pass filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510121391 CN1992516A (en) | 2005-12-28 | 2005-12-28 | Band-pass filter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1992516A true CN1992516A (en) | 2007-07-04 |
Family
ID=38214509
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200510121391 Pending CN1992516A (en) | 2005-12-28 | 2005-12-28 | Band-pass filter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1992516A (en) |
-
2005
- 2005-12-28 CN CN 200510121391 patent/CN1992516A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103633400B (en) | A kind of micro-strip duplexer based on electromagnetism hybrid coupled | |
| JP2010515331A (en) | Power distributor using dual band-CRLH transmission line and power combiner | |
| CN113872532B (en) | Coupling circuit applied to 4G full-band power amplifier and electronic equipment | |
| CN201528031U (en) | L-type coupled-structure dual-mode microstrip bandpass filter | |
| CN109713411B (en) | Microstrip dual-frequency broadband filter | |
| CN101635383A (en) | Micro-strip dual-mode filter with intensified coupling and harmonic suppression characteristics | |
| CN114204240A (en) | Vertical transition structure of broadband in multilayer microwave board | |
| CN202434677U (en) | High pass filter | |
| CN204375890U (en) | Based on the ultra-broadband dual-frequency band pass filter of dual-mode resonator | |
| CN101150215A (en) | Filter | |
| CN101043096A (en) | Low-pass filter with wide cut-off bandwidth | |
| CN101034881A (en) | Band-pass filter | |
| CN104134836A (en) | Planar duplexer based on quarter-wavelength short circuit feeder | |
| CN206564311U (en) | The plane bandpass filter that a kind of Wide stop bands suppress | |
| CN104009271B (en) | A kind of plane bandpass filter based on cascade four resonators | |
| CN200950464Y (en) | Semi-module substrate integrated waveguide filter | |
| US7576628B2 (en) | Low-pass filter | |
| CN100544115C (en) | Dual transfer zero low-pass filter | |
| CN201185220Y (en) | Filter | |
| CN1956255A (en) | Low-pass filter | |
| CN1992516A (en) | Band-pass filter | |
| CN101043095A (en) | Minisize band-pass filter | |
| US8253515B2 (en) | Band-pass filter | |
| CN1956256A (en) | Band-pass filter | |
| CN100468858C (en) | Double frequency filter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |