CN202979142U

CN202979142U - Antenna isolator

Info

Publication number: CN202979142U
Application number: CN 201220684384
Authority: CN
Inventors: 覃达开; 陈进; 钱自进; 鄢家杰; 范西君; 王军军
Original assignee: SICHUAN CHANGHONG ELECTRONIC PARTS CO Ltd
Current assignee: Sichuan Ailian Technology Co ltd
Priority date: 2012-12-12
Filing date: 2012-12-12
Publication date: 2013-06-05
Anticipated expiration: 2022-12-12

Abstract

The utility model relates to an antenna isolator and mainly solves the technical problem about providing an antenna isolator capable of performing EOC (Ethernet over coax) filtering. The technical scheme includes that the antenna isolator comprises an isolator body with an input end, an isolation circuit, an output end, a power source ground wire interface and a cable digital television signal ground wire interface, the isolator body further comprises an EOC filtering circuit which is connected with the isolation circuit; when the input end is connected with the EOC filtering circuit, the isolation circuit is connected with the output end; and when the input end is connected with the isolation circuit, the EOC filtering circuit is connected with the output end. The antenna isolator has the advantages of high integration, strong practicability, low cost and applicability to isolators.

Description

The antenna isolator

Technical field

The utility model relates to a kind of antenna isolator.

Background technology

Along with the large tracts of land of panel TV set and set-top box is universal, repeatedly occurred damaging the phenomenon of even spontaneous combustion because potential difference causes panel TV set or set-top box on market, main cause is that present TV receiving system (television set or set-top box) adopts 3 core power lines more and more, and the two-way ground wire is respectively power ground (ground wire of cable TV) and digital catv signal ground wire (being the metal shell of cable TV signal line).In fact, when fitting up due to the user, the voltage of the voltage of power ground and digital catv signal ground wire is variant, there is the present situation of ground connection confusion in some old-fashioned public housings, may cause digital catv signal and TV receiving system junction to have the situation of heating.Can cause television set spontaneous combustion, the danger such as on fire when situation is serious, common solution is between TV receiving system and cable, increases an antenna isolator, can effectively avoid the potential safety hazard that causes because of potential difference.

In addition, the requirement of and the integration of three networks universal along with the large tracts of land of panel TV and set-top box, the more and more users of China have completed the bilateral network transformation.At present, the mainstream technology that tradition cable TV industry is carried out the bilateral network transformation is EPON+EOC, its function can be with the transmission network of the One-to-All Broadcast formula in traditional cable television system, transform the network that can transmit broadcasting service and bi-directional data traffic as, greatly improved the operation ability of network.This pattern can take full advantage of the coaxial cable resource of existing network, can effectively save the networking cost, and transformation speed is fast, and the terminal equipment cost is lower, reduces customer investment, has been that the Virtual network operator of majority is as the first-selection of bidirectional network reconstruction.

EOC(Ethernet over Coax ether data are transmitted by coaxial cable) be exactly data-signal (being generally 0-65MHz up/down row signal) and digital catv signal (110-870MHz numeral DVB-C signal) the employing frequency multiplexing technique with Ethernet, these two signals are transmitted in same coaxial cable.And jointly transmitting digital catv signal and data-signal in same coaxial cable, data-signal (signal amplitude is approximately up to 120dBuV) will inevitably produce digital catv signal and disturb.

Cable TV two-way network transmission coaxial-cable line attenuation is very large, guaranteeing that user side is in transmission range situation certain between the residential quarter, require the level of RF signals of up/down row signal (0-65MHz) very strong, generally this signal level can arrive the 110-120dBuV left and right, so strong radiofrequency signal enters in TV receiving system by cable, will produce intermodulation product and nonlinear distortion component, the receptivity of severe jamming TV receiving system with digital catv signal (110-870MHz).For solving the interference of up/down row signal, common mode is to increase good EOC filter circuit to realize suppressing interference signal in TV receiving system, thereby reach the application requirements of bidirectional transmission system, make data-signal and digital catv signal enter subscriber household by same cable.TV receiving system is watched digital catv signal, and number video on demand signal is up by the EOC mode.But need to have the EOC filter circuit in each TV receiving system, can increase undoubtedly the cost of TV receiving system.Can consider the EOC filter circuit is separated, carry out filtering at the TV receiving system leading portion.

The utility model content

Technical problem to be solved in the utility model is to provide a kind of antenna isolator that can carry out EOC filtering.

The technical scheme that its technical problem that solves the utility model adopts is: the antenna isolator, comprise have input, the isolator of buffer circuit, output, power ground interface and digital catv signal interface of the ground wire, isolator also comprises the EOC filter circuit, and the EOC filter circuit is connected with buffer circuit; When input is connected with the EOC filter circuit, buffer circuit is connected with output; When input is connected with buffer circuit, the EOC filter circuit is connected with output.

Concrete, described EOC filter circuit comprises the first electric capacity, the second electric capacity, the 3rd electric capacity, the 4th electric capacity, the 5th electric capacity, the first inductance, the second inductance, the 3rd inductance and the 4th inductance; One end of the second electric capacity is connected with input or buffer circuit, and the other end of the second electric capacity is connected with an end of the 3rd inductance, and the other end of the 3rd inductance is connected with buffer circuit or output by the 4th electric capacity; One end of the second electric capacity is connected with an end of the first electric capacity again, and the other end of the first electric capacity is by the first inductance ground connection; The other end of the second electric capacity is connected with an end of the 3rd electric capacity again, and the other end of the 3rd electric capacity is by the second inductance ground connection; The other end of the 3rd inductance is connected with an end of the 5th electric capacity again, and the other end of the 5th electric capacity is by the 4th inductance ground connection.

Concrete, the first electric capacity is 56pF, and the second electric capacity is 22pF, and the 3rd electric capacity is 100pF, and the 4th electric capacity is 56pF, the 5th electric capacity is 150pF; The first inductance is 100nH, and the second inductance is 100nH, and the 3rd inductance is 4.7nH, and the 4th inductance is 100nH.

As the preferred version of technique scheme, described buffer circuit comprises signal capacitance and at least one ground wire capacitance; The signal capacitance be connected between EOC filter circuit and output or input and EOC filter circuit between; The ground wire capacitance is connected between power ground interface and digital catv signal interface of the ground wire.

Further, the signal capacitance is one.

Further, the number of described ground wire capacitance is four.

Further, described ground wire capacitance is parallel with one another.

Preferably, the appearance value of described signal capacitance and ground wire capacitance is 1nF.

The beneficial effects of the utility model are: this antenna isolator carries the EOC filter circuit, improve the uplink/downlink data-signal to the interference of digital catv signal, need not the otherwise designed interlock circuit in TV receiving system, integrated height, practical, with low cost.

Description of drawings

Fig. 1 is the construction unit block diagram of the utility model embodiment;

Fig. 2 is the particular circuit configurations schematic diagram of the utility model embodiment;

Wherein, C1 is that signal capacitance, C2, C3, C4 and C5 are the ground wire capacitance, and C6 is the first electric capacity, C7 is the second electric capacity, C8 is the 3rd electric capacity, and C9 is the 4th electric capacity, and C10 is the 5th electric capacity, L1 is the first inductance, L2 is the second inductance, and L3 is the 3rd inductance, and L4 is the 4th inductance, 1 is the power ground interface, and 2 is the digital catv signal interface of the ground wire.

Embodiment

Below in conjunction with drawings and Examples, the utility model is further illustrated.

Antenna isolator of the present utility model, comprise have input, the isolator of buffer circuit, output, power ground interface and digital catv signal interface of the ground wire, isolator also comprises the EOC filter circuit, the EOC filter circuit is connected with buffer circuit; When input is connected with the EOC filter circuit, buffer circuit is connected with output; When input is connected with buffer circuit, the EOC filter circuit is connected with output.

Embodiment

Fig. 1 is the construction unit block diagram of the utility model embodiment, antenna isolator in the present embodiment, comprise have input, the isolator of buffer circuit, output, power ground interface and digital catv signal interface of the ground wire, isolator also comprises the EOC filter circuit, and the EOC filter circuit is connected with buffer circuit; Input be connected with the EOC filter circuit by buffer circuit, the EOC filter circuit also is connected with output.

As Fig. 2, the EOC filter circuit of the utility model embodiment comprises the first capacitor C 6, the second capacitor C 7, the 3rd capacitor C 8, the 4th capacitor C 9, the 5th capacitor C 10, the first inductance L 1, the second inductance L 2, the 3rd inductance L 3 and the 4th inductance L 4; One end of the second capacitor C 7 is connected with buffer circuit, and the other end of the second capacitor C 7 is connected with an end of the 3rd inductance L 3, and the other end of the 3rd inductance L 3 is connected with output by the 4th capacitor C 9; One end of the second capacitor C 7 is connected with an end of the first capacitor C 6 again, and the other end of the first capacitor C 6 is by the first inductance L 1 ground connection; The other end of the second capacitor C 7 is connected with an end of the 3rd capacitor C 8 again, and the other end of the 3rd capacitor C 8 is by the second inductance L 2 ground connection; The other end of the 3rd inductance L 3 is connected with an end of the 5th capacitor C 10 again, and the other end of the 5th capacitor C 10 is by the 4th inductance L 4 ground connection.

In order to realize better the EOC filter function, the first capacitor C 6 is 56pF, and the second capacitor C 7 is 22pF, and the 3rd capacitor C 8 is 100pF, and the 4th capacitor C 9 is 56pF, and the 5th capacitor C 10 is 150pF; The first inductance L 1 is 100nH, and the second inductance L 2 is 100nH, and the 3rd inductance L 3 is 4.7nH, and the 4th inductance L 4 is 100nH.

Buffer circuit comprises a signal capacitance C1 and four ground wire capacitance C2, C3, C4 and C5 parallel with one another; Signal capacitance C1 is connected between input and EOC filter circuit; Ground wire capacitance C2, C3, C4 and C5 are connected between power ground interface 1 and digital catv signal interface of the ground wire 2; The appearance value of described signal capacitance C1 and ground wire capacitance C2, C3, C4 and C5 is 1nF.

Said elements forms the EOC filter network jointly, form a high performance high-pass filtering circuit, its to the signal suppressing ability of 0-65MHz greater than 30dB, the effective up/down row data-signal in limiting circuitry, avoid data-signal to enter the signal processing unit of TV receiving system, cause television receiver unit the problem that the image mosaic maybe can't receive to occur.Simultaneously, the digital catv signal that 110-858MHz receives is decayed less than 2dB, do not affect the transmission of normal digital catv signal.

Claims

1. antenna isolator, comprise have input, the isolator of buffer circuit, output, power ground interface and digital catv signal interface of the ground wire, it is characterized in that, isolator also comprises the EOC filter circuit, the EOC filter circuit is connected with buffer circuit; When input is connected with the EOC filter circuit, buffer circuit is connected with output; When input is connected with buffer circuit, the EOC filter circuit is connected with output.

2. antenna isolator as claimed in claim 1, it is characterized in that, described EOC filter circuit comprises the first electric capacity (C6), the second electric capacity (C7), the 3rd electric capacity (C8), the 4th electric capacity (C9), the 5th electric capacity (C10), the first inductance (L1), the second inductance (L2), the 3rd inductance (L3) and the 4th inductance (L4); One end of the second electric capacity (C7) is connected with input or buffer circuit, the other end of the second electric capacity (C7) is connected with an end of the 3rd inductance (L3), and the other end of the 3rd inductance (L3) is connected with buffer circuit or output by the 4th electric capacity (C9); One end of the second electric capacity (C7) is connected with an end of the first electric capacity (C6) again, and the other end of the first electric capacity (C6) is by the first inductance (L1) ground connection; The other end of the second electric capacity (C7) is connected with an end of the 3rd electric capacity (C8) again, and the other end of the 3rd electric capacity (C8) is by the second inductance (L2) ground connection; The other end of the 3rd inductance (L3) is connected with an end of the 5th electric capacity (C10) again, and the other end of the 5th electric capacity (C10) is by the 4th inductance (L4) ground connection.

3. antenna isolator as claimed in claim 2, is characterized in that, the first electric capacity (C6) is 56pF, and the second electric capacity (C7) is 22pF, and the 3rd electric capacity (C8) is 100pF, and the 4th electric capacity (C9) is 56pF, and the 5th electric capacity (C10) is 150pF; The first inductance (L1) is 100nH, and the second inductance (L2) is 100nH, and the 3rd inductance (L3) is 4.7nH, and the 4th inductance (L4) is 100nH.

4. as claim 1 or 2 or 3 described antenna isolators, it is characterized in that, described buffer circuit comprises signal capacitance and at least one ground wire capacitance; The signal capacitance be connected between EOC filter circuit and output or input and EOC filter circuit between; The ground wire capacitance is connected between power ground interface and digital catv signal interface of the ground wire.

5. antenna isolator as claimed in claim 4, is characterized in that, the signal capacitance is one.

6. antenna isolator as claimed in claim 4, is characterized in that, the number of described ground wire capacitance is four.

7. antenna isolator as claimed in claim 6, is characterized in that, described ground wire capacitance is parallel with one another.

8. antenna isolator as claimed in claim 7, is characterized in that, the appearance value of described signal capacitance and ground wire capacitance is 1nF.