CN2323516Y - VHF low band radio frequency surface acoustic wave filter - Google Patents
VHF low band radio frequency surface acoustic wave filter Download PDFInfo
- Publication number
- CN2323516Y CN2323516Y CN 97231167 CN97231167U CN2323516Y CN 2323516 Y CN2323516 Y CN 2323516Y CN 97231167 CN97231167 CN 97231167 CN 97231167 U CN97231167 U CN 97231167U CN 2323516 Y CN2323516 Y CN 2323516Y
- Authority
- CN
- China
- Prior art keywords
- acoustic wave
- surface acoustic
- wave filter
- radio frequency
- utility
- 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.)
- Expired - Fee Related
Links
Landscapes
- Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)
Abstract
The utility model relates to a surface acoustic wave filter used at the front end of the adjacent frequency of cable televisions for the VHF low band RF treatment. The utility model adopts piezoelectric crystal Y128 DEG lithium niobate as a base sheet and is composed of two transducers and a multi-strip coupler, and the weighting of the transducers totally adopts digit cutting weighting. The performance index of the utility model is obviously superior to past inductance-capacitance filters and helical filters.
Description
The utility model relates to a kind of low section of very high frequency(VHF) radio frequency processing Surface Acoustic Wave Filter that is used for the adjacent front end frequently of cable TV.
The adjacent front end system frequently of cable TV divides two big classes: intermediate frequency process front end and radio frequency processing front end.The choke-condenser filter or the screw-filter of radio frequency processing front end use in the past because performance index are poor, regulate shortcomings such as complexity, consistency of product and poor stability, more and more can not satisfy the requirement of front end manufacturer large-scale production.
The purpose of this utility model is to propose a kind of low section of very high frequency(VHF) Surface Acoustic Wave Filter of being made up of transducer and multistrip coupler, it has that passband fluctuation is little, band outer suppresses high, Group Delay Ripple is little and need adjustment, high conformity, characteristics such as reliable and stable, thereby solved the existing in prior technology problem.
The technical scheme that the utility model adopted is: it is made up of two transducers on the piezoelectric chip and multistrip coupler, said transducer and multistrip coupler are by the aluminium film that is plated on the piezoelectric chip, make through semiconductor planar technology, its input and output electrode by the lead-in wire with base with the signal input and output, the weighting of transducer is all adopted and is cut the finger weighting scheme.
The low section of very high frequency(VHF) in cable TV radio frequency processing Surface Acoustic Wave Filter (comprising that TV 1 channel is to～5 channels) filter, because band connection frequency lower (49.75～72.25 megahertzes, 77.25～91.75 megahertzes), relative bandwidth broad (greater than 8%), variations in temperature and the frequency drift that causes is less, can adopt the piezoelectric Y128 ° lithium niobate of high coupling coefficient, high-temperature coefficient, be fit to the use of multistrip coupler, take two methods for designing that refer to weighted transducer of cutting.
Radio frequency processing Surface Acoustic Wave Filter in the utility model ,-1dB bandwidth are 6.5 megahertzes, and the squareness factor of device is less than 1.3, and passband fluctuation is less than 1dB, and band is outer to be suppressed greater than 40dB, and Group Delay Ripple is less than 60ns.The performance index of device are better than traditional choke-condenser filter and screw-filter.
Advantage of the present utility model is that volume is little, in light weight, compare with traditional choke-condenser filter, screw-filter, have that group delay characteristic preferably, less passband fluctuation, higher band are outer to be suppressed and produce good reproducibility, need not to adjust and advantage that temperature stability is good, especially be fit to large-scale mass production.
Fig. 1 is the partial cutaway structural representation of the utility model embodiment.
Fig. 2 is the chip structure schematic diagram among Fig. 1.
Fig. 3 is the amplitude-frequency response of Fig. 2 embodiment.
Below in conjunction with accompanying drawing the utility model preferred embodiment is described further.
As shown in Figure 1, it is the structural representation that is used for the low section of the very high frequency(VHF) radio frequency processing Surface Acoustic Wave Filter embodiment of the adjacent front end frequently of cable TV, the utility model is made up of two transducers 6,7 and many joint couplers 8 on chip 2, be by the aluminium film that is plated in piezoelectric chip, make through semiconductor planar technology.Surface Acoustic Wave Filter chip 2 is bonded on the base 1, and it inputs or outputs electrode and links to each other with pin 4 by lead-in wire 3.As depicted in figs. 1 and 2.
Fig. 2 is the structural representation of 4 channel Surface Acoustic Wave Filter chips 2 among Fig. 1 embodiment.By two transducers 6 on the Y128 ° of lithium niobate substrate 5 and 7 and multistrip coupler 8 form.Two transducer weightings all take to cut the finger weighting, and finger width and interval are λ/8 (λ is the centre frequency wavelength), and transducer length is 90 λ, and width is 40 λ.Multistrip coupler 8 finger width and interval are 3 λ/16, and length is 30 λ, and width is 80 λ.
Fig. 3 is the amplitude-frequency response of Fig. 2 embodiment.The squareness factor of the utility model device is less than 1.3, and passband fluctuation is less than 1dB, and band is outer to be suppressed greater than 40dB.Its amplitude-frequency response, as shown in Figure 1.
Claims (2)
1. the low section of a very high frequency(VHF) radio frequency Surface Acoustic Wave Filter is characterized in that it is made up of two transducers and multistrip coupler on piezoelectric substrate, its input and output electrode by lead-in wire and base with the signal input and output.
2. according to the low section of the said very high frequency(VHF) of claim 1 radio frequency Surface Acoustic Wave Filter, it is characterized in that said transducer, its weighting is all adopted and is cut the finger weighting.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 97231167 CN2323516Y (en) | 1997-12-31 | 1997-12-31 | VHF low band radio frequency surface acoustic wave filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 97231167 CN2323516Y (en) | 1997-12-31 | 1997-12-31 | VHF low band radio frequency surface acoustic wave filter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2323516Y true CN2323516Y (en) | 1999-06-09 |
Family
ID=33943450
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 97231167 Expired - Fee Related CN2323516Y (en) | 1997-12-31 | 1997-12-31 | VHF low band radio frequency surface acoustic wave filter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2323516Y (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102393271A (en) * | 2011-11-09 | 2012-03-28 | 东华大学 | Surface acoustic wave pressure sensor based on multiple couplers |
| CN101895271B (en) * | 2006-03-17 | 2013-02-27 | 株式会社村田制作所 | Elastic wave resonator |
| CN106230401A (en) * | 2016-07-15 | 2016-12-14 | 南京大学 | A kind of slow sound chronotron based on surface acoustic wave phonon crystal |
-
1997
- 1997-12-31 CN CN 97231167 patent/CN2323516Y/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101895271B (en) * | 2006-03-17 | 2013-02-27 | 株式会社村田制作所 | Elastic wave resonator |
| CN102393271A (en) * | 2011-11-09 | 2012-03-28 | 东华大学 | Surface acoustic wave pressure sensor based on multiple couplers |
| CN106230401A (en) * | 2016-07-15 | 2016-12-14 | 南京大学 | A kind of slow sound chronotron based on surface acoustic wave phonon crystal |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1073306C (en) | Surface acoustic wave device | |
| CN109787579A (en) | A kind of SAW resonator with the spuious function of reduction | |
| EP0322622A2 (en) | Monolithic lattice saw filter | |
| US6504454B2 (en) | Longitudinally coupled surface acoustic wave filter | |
| CN2323516Y (en) | VHF low band radio frequency surface acoustic wave filter | |
| CN115567025A (en) | Multilayer structure spurious response free SH type surface acoustic wave filter | |
| CN108512525B (en) | Sound surface transverse wave resonant filter | |
| US20210184647A1 (en) | Interdigital transducer arrangements for surface acoustic wave devices | |
| CN2323517Y (en) | VHF high band radio frequency surface acoustic wave filter | |
| CN219107409U (en) | SAW filter for Band1 receiving frequency Band | |
| US20120119848A1 (en) | Superlattice crystal resonator and its usage as superlattice crystal filter | |
| CN202737825U (en) | SR580T75 type low loss SAW resonator | |
| US5625329A (en) | Surface acoustic wave filter with an optimizing reflector thickness-to-wavelength ratio | |
| CN111224209A (en) | Waveguide band-pass filter based on waveguide re-cut-off characteristic and design method thereof | |
| CN101217210B (en) | A three frequency band filter based on parallel coupled line structure | |
| CN203504508U (en) | Surface acoustic wave filter used for mobile phone | |
| CN219087114U (en) | SAW filter for Band7 receiving frequency Band | |
| CN114421923A (en) | High-performance surface acoustic wave filter | |
| JP2709713B2 (en) | Resonator filter | |
| CN201312289Y (en) | SF24K400 narrow-band low-insertion loss saw filter | |
| CN115955212B (en) | SAW filter with enlarged bandwidth | |
| JPH07122965A (en) | Surface acoustic wave filter | |
| CN202918253U (en) | SF1000M36A type surface acoustic wave filter | |
| CN217849391U (en) | Duplexer and radio frequency communication device | |
| CN201213251Y (en) | SAW filter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |