DE10219847A1 - Method and device for generating at least one transponder in the satellite intermediate frequency level - Google Patents

Abstract

The invention relates to an improved method and an improved device for producing at least one transponder (33) in the satellite intermediate frequency plane and for combining said transponder with the satellite intermediate frequency band. The improved method and device are characterised in that the mixing products of the local oscillators for the lower and upper satellite bands are outside the satellite intermediate frequency bands, the transponder (33, 33a, 33b, ) is produced by means of direct conversion into the desired frequency band, and the transponder and a selected frequency band are diverted onto a cable.

Description

The invention relates to a method and a Device for generating at least one transponder in the Satellite intermediate frequency level according to the generic term of Claims 1 and 7 respectively.

With conventional single reception systems can on the subscriber side, the converter can be controlled so that both the vertical as well as the horizontal polarizations can be received. Switching the Polarization is traditionally done by switching one Supply voltage of 14 V (for the reception of the vertical Polarizations) to 18 V (for receiving the horizontal Polarizations). With newer systems can for example by feeding a frequency tone of 22 kHz also a switch from a lower to an upper Frequency band can be made, what more Satellite programs can be received.

While always with such a single reception system only one participant via the connected receiver can receive the program selected by him so-called twin converters (twin LNB) receive both Polarizations, for example for both the mentioned lower as well as for the upper frequency band. However, this requires that the Comprehensive converter circuit Input reception circuitry basically two derivatives to connected subscriber or receiver includes, then for example, a program on the connected TV received and via a connected to the twin receiver Video device (VCR) on the second antenna line to be able to record another program.

From DE 197 13 124 C2, however, a satellite Reception system became known with the two participants on a single antenna lead separately Can receive programs. This is done according to the above mentioned prior publication suggested that two Converter or a twin converter can be used, whereby the two converter outputs at least indirectly be interconnected, and in one of the two Converter output lines switched a receiving module is what selectively different Satellite programs with vertical or horizontal polarization are receivable. This is what is received Satellite program in this receiver module in this one Received module assigned frequency signal implemented and in the Subscriber antenna line fed. Over the other As usual, the converter output is also from Recipients selected and in the converter accordingly controlled upper or lower vertically or horizontally polarized signal received in the IF plane.

Otherwise, multiple participants can use one Antenna line only then independent of several programs received when a so-called coupling station is used becomes. So-called satellite frequency converters are used used, so-called Sat. ZF1 converter, in which individual frequency ranges, for example transponders with approx. 40 MHz bandwidth, selected and newly combined on the single cable can be transmitted. Because of the available Bandwidth of 950-2150 MHz and the required The distance between the transponders is the number of transmitted transponder restricted. The number of connectable receiver on the cable network is in contrast free.

However, the selection of the transponders by the receiver made, d. H. that each receiver has a set of satellite ZF1 / Sat.-ZF1 converter and the upstream matrix controlled, the program selection is again unlimited, however, the number of receivers that can be connected is the same the number of the mentioned Sat. IF1 / Sat. IF1 converter. In contrast, only two or at least very few should Receiver are supplied with a cable, so is that Combination of an implemented satellite IF1 / satellite IF1 band for the receiver and a selected transponder for the a second receiver is an advantageous solution.

However, the Sat.-ZF1 / Sat.-ZF1 converter is available of a transponder based on the known techniques very complex and expensive. For example, at State of the art the Ku band (10700 MHz to 12750 MHz) by mixing with a first local oscillator of 9750 MHz in a satellite IF1 frequency range from 950 to 1950 MHz and with a second local oscillator of 10600 MHz for example in a satellite IF1 frequency range of 1100 MHz implemented up to 2150 MHz. This already brings some Disadvantage that due to the local oscillator frequencies chosen unwanted mixed products are generated which in the used intermediate frequency level fall.

Around individual transponders from these frequency bands must select a matrix for the selection of the Frequency bands are used. Furthermore, with a Mixer and a tunable local oscillator with a Tuning frequency from 1400 MHz to 2700 MHz, for example implementation in the intermediate frequency level with an IF Frequency of 480 MHz. Because of the additional need for image rejection must also a tunable bandpass filter in front of the mixer be used. With a further provided downstream SAW filter of 480 MHz is then the selected transponder selected. To dampen the SAW Equalizing filters also requires additional reinforcement be made. Finally, another one Mixer with another local oscillator Implementation back to the Sat. ZF1 level. So as mentioned is the need to use two local oscillators as well as the necessary shielding and also the selection for Avoiding undesirable mixed products is very disadvantageous.

The object of the present invention is therefore based on from the generic state of the aforementioned Technology a transponder selection with significantly reduced To create effort and space. Such Transponder selection should have at least one twin reception on one Allow one-cable structure.

The object is achieved according to the method corresponding to that in claim 1 and with respect to Device according to the features specified in claim 7 solved. Advantageous embodiments of the invention are shown in specified in the subclaims.

It is surprising that according to the invention with a comparatively low cost such a solution for one-cable structures is feasible. For each recipient, a is selected certain program implemented in a transponder area. This transponder can then be used with a satellite ZF1 band can be combined, with the second participant the received programs transmitted via this satellite IF1 band receives.

The advantages of the solution according to the invention are all the more more evident when dealing with the difficulties and disadvantages of the prior art are compared. So had to State of the art the combination of a transponder with a lower frequency band because of the lower Frequency limit of 950 MHz in the frequency range between 900-950 MHz. With a combination of the Transponders with an upper frequency band must be used despite high Selection by the SAW filter when implementing the Transponders to suppress unwanted signals below 1100 MHz then a crossover with very high selection can be used. This is not a insignificant technical effort.

In contrast, a first implementation of the lower satellite intermediate frequency band with a Local oscillator of preferably exactly 9550 MHz and a first one Implementation of the upper satellite frequency band with one Local oscillator of preferably exactly 1625 MHz proposed. This results in a usable frequency range of approx. 900 to 1000 MHz for the new transponder frequency. The Mixed products of the two local oscillators are then included 1075 and 2150 MHz exactly at the lower and upper limits the satellite intermediate frequency bands, here at 1150 up to 2150 MHz for the lower or 1075 to 2125 MHz for the upper band and interfere because of the protective distances on the Band limits no signal. Of course, from the local oscillators mentioned above also deviate values of preferably less than ± 200 MHz, preferably less than ± 100 MHz or less than ± 50 MHz or even less used to be at least ± 10 MHz approximately take advantage of the advantages of the invention can. Correspondingly in a preferred embodiment the features according to subclaim 2 or 8 is a first Implementation of the lower satellite frequency band with one Local oscillator from e.g. B. 9600 MHz and a first implementation the upper satellite frequency band with a Local oscillator from e.g. B. 13850 MHz proposed. Based on these compared to the prior art other local oscillator Frequencies it becomes possible that the lower limit for that lower frequency band with the lower limit for the upper frequency band (high band) with 1100 MHz each matches. From the above description it can be seen that there is not one for the second mixer Local oscillator frequency of 10600 MHz, for example is used, but in contrast a local oscillator Frequency above the top of the top Frequency band. As a result, according to the invention made inverse implementation such that the above the upper limit of the upper frequency band Frequency range (i.e. above 12750 MHz) into one Range below 1100 MHz is implemented by Otherwise, transponders and satellite signals are completely free is.

This can be done by simply implementing the mixer Use only one tunable oscillator and only a subsequent selection of a suitable one Bandpass filter with a freely selectable transponder, for example a satellite IF1 / satellite IF1 center frequency of 950 MHz be implemented.

In a preferred embodiment, such Transponder with a freely selectable satellite intermediate Combined frequency band, preferably over a Crossover. This results in the converted frequency band a frequency range of, for example, less than 1000 MHz, with the desired transponder with the highest possible frequency without distortion by the lower Crossover frequency filter. Preferred is therefore also a terrestrial frequency range switch on a crossover. This results in the desired transponder then even a bandpass filter Characteristics.

From the description there is a significant advantage that, for example, a tracking filter, a tunable one Bandpass filter is not required because of the Mirror frequencies always above the converted band ranges are the two local oscillators of the Converter (LNB) can be implemented.

Since only a few components are required and only one low demands are placed on the shielding a preferred embodiment of the converter described and the crossover directly into a converter (LNB) can be installed. It can be used with everyone at the Converter (LNB) connected two receivers or cables a twin receiver for a complete independent Program selection can be connected.

For the sake of completeness it is mentioned that at a multi-user system a converter with the two Local oscillators are also spatially separated from a matrix with converters and a combination of the selected ones Transponders with a selected Sat. ZF1 band can be positioned. Finally, however, it is according to the invention also possible, especially with special quality of Crossover and the filter used, e.g. B. also two or three selected transponders with the not implemented satellite ZF1 band to combine. Finally, you can according to the invention even several transponder tapes without Combination combined with a satellite ZF1 band become.

Further advantages, details and features of the invention follow from the drawings illustrated embodiments. Show in individual:

Fig. 1 is an illustration of an improved LNB's with improved selected local oscillator frequencies for the first and second local oscillator;

FIG. 1a is an illustration of an inventive universal twin LNBs mi improved determination of local oscillators LO1 and LO2;

Figure 2 shows an inventive universal twin LNB with additionally generated transponder combined with a freely selectable satellite ZF1-band via a cable crossover and derivative-A is fed into a.

FIG. 2a schematic representation of a transponder with a transponder width of 40 MHz and a center frequency of 950 MHz;

Fig. 3 is a schematic representation of the combination of the transponder with a satellite ZF1 band;

FIG. 4 shows a representation corresponding to FIG. 3 when a terrestrial frequency range is also added;

Fig. 5 is an illustration of a one-cable twin LNB;

Fig. 6 is the representation of a one-cable Quattro- solution;

FIG. 7a is a switching matrix according to the prior art;

FIG. 7b is a switch matrix according to the invention extended;

Fig. 8 is an example of a one-cable converter Tripple- solution;

. FIG. 9 is an illustration of the combination of two transponders areas with satellite ZF1- band, as can be seen in realization of a circuit according to Fig 8;

FIG. 10 is an example of a one-cable quad LNB solution; and

Fig. 11 is an illustration of four with respect to a combined transponder according to the circuit of Fig. 10.

In Fig. 1, the basic structure of a satellite receiving system according to the invention with a so-called universal twin converter (LNB) 1 is shown in a schematic arrangement. As is known from a satellite antenna. B. received via a so-called horn, not shown in detail, the vertically and horizontally polarized signals in an upper and lower frequency band and implemented via a polarization switch in two branches 1 'and 1 ".

In both branches 1 'and 1 "shown in FIG. 1, an amplifier arrangement 3 and a downstream bandpass filter 5 are provided, for example.

A mixer 7 is then arranged in each of the two branches. Furthermore, two local oscillators 9 and 11 are provided, via which the respective received satellite frequency is converted into a satellite intermediate frequency in the mixers 7 . As is known, the downlink frequencies of the satellites in the Ku band in Europe are 10700 MHz to 12750 MHz. The lower frequency band (low band) ranges from 10700 MHz to about 11700 MHz. The upper frequency band (high band) extends from 11700 MHz to 12750 MHz. If the universal twin converter according to FIG. 1 in the upper branch 1 ′ is to be used to convert the lower frequency band into the satellite intermediate frequency band range, this will be done with the local oscillator frequency of 9550 MHz, that is to say with the local oscillator frequency of the local oscillator 9 operating at a lower frequency in the respective assigned mixer 7 . This converts the lower received satellite frequency band from 10700 MHz to 11700 MHz into a satellite intermediate frequency from 1150 MHz to 2150 MHz.

If the upper frequency band range, for example the vertically or horizontally polarized received signals in the first or in the second branch 1 ', 1 ", is to be converted accordingly, this is done with the second local oscillator 11 with the high local oscillator frequency of 10625 MHz chosen according to the invention there is an inverse conversion of the received upper satellite frequency band from 11700 MHz to 12750 MHz into a satellite IF range from 1075 MHz to 2125 MHz.This means that the conversion takes place in such a way that the mixed product of the two local oscillator frequencies does not translate into the Satellite IF level falls into it, but in the present case is carried out in such a way that the lower and the upper received satellite frequency band are implemented at the upper end of the satellite intermediate frequency level. This also ensures that the mixed products of the two local oscillator frequencies with 1075 MHz and 2150 MHz exactly to the lower one The upper and lower limits of the satellite intermediate frequency bands are 1150 to 2150 MHz for the lower and 1075 to 2125 MHz for the upper band and therefore do not interfere with any signal due to the protective distances at the band limits. This is made possible, among other things, by selecting the higher local oscillator frequency so that it is higher than the lower end of the upper frequency band, i.e. at 13850 MHz higher than the lower end of the upper frequency band at 12750 MHz.

The local oscillators 7 can again be followed by single- or multi-stage amplifier arrangements 8 .

A universal twin LNB improved according to the invention is now shown with reference to FIG. 1a. The basic principle is similar to that of FIG. 1. The only difference in this exemplary embodiment is that the first local oscillator frequency LO1 is 9600 MHz and the second local oscillator frequency LO2 is 13850 MHz. This translates the lower satellite frequency band from 10700 to 11700 MHz into a satellite IF from 1100 MHz to 2100 MHz. The upper satellite frequency band is also converted into a satellite intermediate frequency from 1100 MHz to 2150 MHz. In other words, the conversion takes place in such a way that the lower limit frequency for the lower frequency band is the same as for the received upper frequency band and in the exemplary embodiment shown is significantly higher than the lower frequency limit of the low band for a standard universal LNB.

In the exemplary embodiment shown in FIG. 1a, the corresponding conversion of the upper satellite frequency band into the satellite IF level takes place using a local oscillator frequency that lies above the upper satellite frequency band.

At the two outputs 15 of the two branches 1 ', 1 "is connected a 2-x-2 matrix 19 , at whose two outputs 21 a and 21 b, as is known, one subscriber could be connected, the lower or upper one of the vertical or horizontal polarizations.

According to the invention but is now connected to the one output, in the embodiment shown at the output 21b a further mixer 23, which via a variable frequency oscillator 25, for example, from 2025 to 3100 MHz with a subsequent selection, z. B. by means of a bandpass filter 26 at z. B. 950 MHz center frequency and a bandwidth of 40 MHz generates a freely selectable transponder, as shown with reference to Fig. 2a.

The transponder branch 29 b provided with the mixer 23 and a bandpass filter 26 can now be connected to the branch 29 a connected to the other output 21 a via a downstream crossover 27 . The output 27 a of the crossover 47 is thus connected to a single antenna cable 31 , usually a coax cable. This one-cable solution then enables twin reception. As a result, the transponder 33 generated is combined with a freely selectable satellite IF band 35 , as is shown schematically in FIG. 3. This results in a frequency range of z for the converted frequency band, ie for the transponder. B. less than 1000 MHz, the frequency band representing the desired transponder with the highest possible frequency, at a center frequency of z. B. 950 MHz without any distortion by the low-pass filter of the crossover.

Based on Fig. 4 is shown, for example, that can be switched in via a further crossover, a terrestrial portion 37 yet, which adjoins at 862 MHz. This even results in a bandpass filter characteristic for the desired transponder 33 .

An extension of the principle explained in the sense of a one-cable-twin converter is described with reference to FIG. 5. A converter structure is used here, which ultimately feeds a 4 × 4 matrix 19 via four branches 1 a to 1 d, so that at the output of this matrix the lower frequency band received via the vertical polarization is known, that via the vertical Upper frequency band received polarization, the lower frequency band received via horizontal polarization and, for example, the upper frequency band received via horizontal polarization, are each present separately and simultaneously. As a result, an arbitrarily large number of participants can be connected by appropriately linking several matrixes. In the exemplary embodiment shown, however, two outputs are connected together according to the invention at outputs 21 a to 21 d of the matrix circuit 19 via a subsequent crossover 27 , one output of the matrix being switched through directly over a distance 29 a with the input of the crossover and in the other branch a so-called transponder branch is formed 29 b, in which again a mixer 23 with a subsequent band pass filter 26 is arranged while the mixer is operated with a tunable oscillator 25 with a suitable frequency band. A twin operation can then be carried out at the outputs 27 a of the then two crossovers 27 .

This principle can be expanded accordingly, as is explained, for example, using a 4 × 8 matrix 19 with reference to FIG. 6. With corresponding expansion at the four outputs 27 a of the four crossovers 27 , twin operation is possible in each case.

Referring to Fig. 7a and 7b is shown, the matrix may also be arranged separately from the local oscillators of the converter (LNB). In Fig. 7a while a conventional converter is shown, at the four outputs in the IF level, respectively the upper and abuts the lower frequency band of the vertically or horizontally received signals. It is indicated in FIG. 7a that the two local oscillators 9 and 11 can operate with a local oscillator frequency of 9600 MHz or 13850 MHz, as shown with reference to FIG. 1a, or as explained with reference to FIG. 1 , with a local oscillator frequency of 9550 MHz or 10625 MHz. The conversion in the satellite intermediate frequency level then takes place accordingly, as has been explained with reference to the exemplary embodiments according to FIG. 1 or FIG. 1a.

Spatially separated from this, for example, a switch matrix 37 , as is known from the prior art, can then be connected downstream of the converter shown in FIG. 7a. Several of the switch matrix arrangements can also be connected in series one behind the other. In this case, as in the previous examples, two outputs, namely a first branch 29 a and a transponder branch 29 b, are again connected together at the outputs shown below in FIG. 7 b, again via a crossover 27 .

In this example as well, as in the exemplary embodiment according to FIG. 4, the output 27 a of the relevant crossover 27 is connected to the input of a further crossover, a terrestrial signal being fed in at the second input of the downstream crossover 39 . Twin operation can then again be carried out at the output 41 of these downstream crossovers 39 , for which purpose an antenna cable 31 is usually connected in each case.

Referring to Fig. 8 and 9 is explained that not only a transponder-band area with a satellite IF-band region may be combined, but that also a so-called one-cable triple-converter solution is possible, offset in the example, two spaced- Transponder frequency ranges can be combined with a satellite IF band range.

In this case, using a 4 × 6 matrix, three outputs 21 a, 21 b, 21 c on the one hand and 21d, 21e, 21f on the other hand are interconnected via three parallel lines of a downstream crossover 27 , with one branch 29 a in each case between the matrix and the crossover is switched through, in a second branch 29 b again a mixer controlled by a local oscillator, preferably with a downstream bandpass filter for generating a first transponder 33, for example with a transponder center frequency of 950 MHz and finally in the third branch line 29 c another mixer with a further local oscillator is provided, the local oscillator frequency being chosen such that a second transponder 33 a with a transponder center frequency of, for example, 1020 MHz is generated via the mixer. As shown in FIG. 9, the two transponder ranges are also at a distance below the lower limit of 1100 MHz of the satellite intermediate frequency band range which then adjoins upwards.

Finally, the principle described could also be expanded in accordance with FIGS. 10 and 11 in such a way that a plurality of transponders with a frequency spacing from one another are generated, and these transponder branches 29 are then combined via a crossover network. This allows multiple transponders to be fed onto a single common antenna line.

Claims (12)

1. Method for generating at least one transponder ( 33 ) in the satellite intermediate frequency level (satellite IF level) in combination with at least one further transponder ( 33 a, 33 b,...) And / or in combination with a frequency band ( 35 ) converted from an upper or a lower satellite frequency band into the satellite IF level, for which purpose a converter arrangement ( 1 ) with an integrated or downstream matrix ( 19 , 37 ) with at least two outputs ( 21 a, 21 b) is used, the signals present at the outputs ( 21 a, 21 b) preferably being fed into at least one connected antenna line ( 31 ) via a summation circuit or a crossover ( 27 ), characterized by the following further features the lower and the upper received satellite frequency band are converted to the upper end of the satellite intermediate frequency level, - For the conversion of the lower and the upper satellite frequency band into the satellite frequency level, a local oscillator combination is used such that the mixed products of the local oscillators do not fall within the occupied satellite frequency, and - The transponder ( 33 , 33 a, 33 b,...) is preferably generated in the range from 950 to 1075 MHz by means of direct conversion. 2. The method according to claim 1, characterized in that a combination of the local oscillators Underlay for the lower satellite frequency band and Overlay is used for the upper satellite frequency band. 3. The method according to any one of claims 1 to 2, characterized characterized that the lower frequency limit of the in the Satellite intermediate frequency level implemented lower Satellite frequency band and the lower frequency limit the implemented in the satellite intermediate frequency level upper satellite frequency band is approximately 1100 MHz. 4. The method according to any one of claims 1 to 3, characterized in that the transponder ( 33 ) by simple implementation with a mixer ( 23 ) and a tunable oscillator ( 25 ) preferably with a frequency range from 2025 to 3100 MHz and preferably a subsequent selection is generated by means of a bandpass filter ( 26 ) or a lowpass filter. 5. The method according to any one of claims 1 to 4, characterized in that for generating at least one second transponder ( 33 a) and optionally further transponders ( 33 b, 33 c...) At correspondingly provided further outputs ( 21 a, 21 b , 21 c..) Of a matrix ( 19 , 37 ) connected downstream of the converter ( 1 ) each further mixer ( 25 ) serving for simple implementation, each with a tunable local oscillator ( 25 ) and preferably each with a downstream selection in the form of a bandpass filter ( 26 ) are used, the transponders ( 33 , 33 a, 33 b,...) Thus produced preferably being fed via a crossover ( 27 ) into a common antenna line ( 31 ). 6. The method according to any one of claims 1 to 5, characterized in that in addition to the at least one transponder ( 33 ) in the common antenna line ( 31 ) an upper or lower satellite frequency band ( 35 ) implemented in the satellite intermediate frequency level is fed , whose lower frequency limit in the satellite intermediate frequency level is above the transponder ( 33 ). 7. Device for generating at least one transponder ( 33 ) in the satellite intermediate frequency level (satellite IF level) in combination with at least one further transponder ( 33 a, 33 b,...) And / or in combination with a frequency band converted from an upper or a lower satellite frequency band into the satellite IF level, with a converter arrangement preferably with an integrated or upstream matrix ( 19 , 37 ) with at least two outputs ( 21 a, 21 b) for feeding of the signals present there, preferably via a downstream crossover ( 27 ) or a summation circuit in a connected antenna line ( 31 ), characterized by the following further features the structure is such that the lower and the upper received satellite frequency band are implemented at the upper end of the satellite intermediate frequency level, - The implementation of the lower and the upper satellite frequency band in the satellite frequency level is based on a local oscillator combination such that the mixed products of the local oscillators do not fall within the occupied satellite frequency, and - The transponder ( 33 , 33 a, 33 b,...) can be generated by direct conversion into the desired frequency band. 8. The device according to claim 7, characterized in that that the structure is such that over the Local oscillators a combination of subposition for the lower one Satellite frequency band and overlay for the upper one Satellite frequency band is used. 9. The device according to claim 7 or 8, characterized characterized that the lower frequency limit of the in the Satellite intermediate frequency level implemented lower Satellite frequency band and the lower frequency limit the implemented in the satellite intermediate frequency level upper satellite frequency band is approximately 1100 MHz. 10. Device according to one of claims 7 to 9, characterized in that the transponder ( 33 ) by simple implementation with a mixer ( 23 ) and a tunable oscillator ( 25 ) preferably with a frequency range from 2025 to 3100 MHz and preferably a subsequent selection can be generated by means of a bandpass filter ( 26 ). 11. The device according to one of claims 7 to 10, characterized in that for generating at least one second transponder ( 33 a) and optionally further transponders ( 33 b, 33 c...) At correspondingly provided further outputs ( 21 a, 21 b , 21 c..) Of a matrix ( 19 , 37 ) connected downstream of the converter ( 1 ) each further mixer ( 25 ) serving for simple implementation, each with a tunable local oscillator ( 25 ), preferably with a downstream selection in the form of a bandpass filter ( 26 ) are provided, the transponders ( 33 , 33 a, 33 b,...) generated in this way being able to be fed preferably into a common antenna line ( 31 ) via a crossover ( 27 ). 12. Device according to one of claims 7 to 11, characterized in that in addition to the at least one transponder ( 33 ) in the common antenna line ( 31 ), an upper or lower satellite frequency band implemented in the satellite frequency level, the lower of which can be fed Frequency limit in the satellite frequency level is above the transponder ( 33 ).