Patent Application
20100271985
The invention concerns a device for receiving and transmitting mobile telephony signals with multiple transmit-receive branches in accordance with the preamble of claim 1.
In mobile telephony there is a constant requirement to achieve ever-higher transmission speeds. This being the case various technical standards have been created which have brought continued improvements in transmission methods. Thus in mobile telephony a distinction can be made, for example, between systems such as GSM (Global System for Mobile Communications), HSCSD (High Speed Circuit Switched Data), EDGE (Enhanced Data rates for GSM Evolution), UMTS (Universal Mobile Telecommunications System) and for example HSPA (High-Speed Packet Access). Here the UMTS method is referred to as a third generation technology.
Apart from this UMTS technology a further development, the Long Term Evolution (LTE) technology is now on the horizon which will supersede or further develop UMTS. In this respect the LTE technology is also being referred to as the 3.9-generation, which thus in terms of its timing comes just before the fourth generation technologies, but which nevertheless compared to alternative technologies such as WiMAX should allow a comparatively cost-effective and “seamless”, and therefore evolutionary, further development from UMTS to LTE.
Here, as will be known, the LTE technology uses Orthogonal-Frequency-Division-Multiplexing methods (OFDM), which ultimately are based on the FDM technology, that is Frequency-Division-Multiplexing. With FDM it is a case of a telecommunications multiplexing method, with which several signals can be transmitted simultaneously distributed over multiple carriers, whereby the multiple carriers are assigned different frequencies. With the orthogonal FDM method it is also a case of a multi-carrier modulation method, in which multiple orthogonal carrier signals are used for digital data transmission.
Furthermore, here the LTE technology is also based on the MIMO technology, for which antennas are used which take account of the Multiple-Input-Multiple-Output principle.
LTE technology is also characterized here, for example, by comparatively low latency periods, whereby voice services (VoIP) or for example also video telephony can be improved. So, for example, with the 4×4 MIMO technology a peak data rate of, for example, more than 300 Mbps can be achieved in the downlink. In the process the uplink still achieves a peak data rate of over 75 Mbps, if for example a single antenna is used.
Here, in known mobile telephony networks, on the base station side as a rule antenna are used which mainly have one or two antenna systems for the transmit branch and more often than not two antenna systems for the receive branch.
The term “antenna system” here can mean two separate antennas, or also a dual polarized antenna with two decoupled connections for the two polarization planes which are perpendicular to one another. In the case of reception therefore, a polarization diversity that improves the reception quality or also a so-called space diversity is or are present.
Conventional mobile telephony base stations normally comprise all the essential parts that are necessary for operating such a base station. In order to minimize additional losses both in the transmission and reception direction, however, a module referred to as a Remote Radio Head (RHH) which is separate from the radio server and remote from this, i.e. as a rule in the vicinity of the antenna on a mast, can be provided. This essentially takes care of transmission and reception amplification and modulation of the carrier with the I/Q-signals transmitted via the optical interface. Communication between the radio server and the remote radio head RRH provided separately from this and in the vicinity of the mast preferably takes place via an optical interface.
As already mentioned in the latest mobile radio standard generation the use of antennas is envisaged which comprise radiator devices in various slots.
This opens up the possibility outlined at the outset of operating the antenna using the so-called MIMO technology. Here several data streams are transmitted both on the transmission side and the reception side via the transceiver unit to the different antenna systems.
This also means that both for MIMO operation of the base station and also when conventional remote radio heads (RHH) are used the number of transceiver units required increases. Even if several transceiver branches are combined in a single housing, normally the number of A/D converters, the number of signal conditioning modules and the number of reception amplifiers increase approximately linearly with the number of antenna systems used.
A transceiver module for operating a mobile telephony base station employing MIMO technology is, for example, known from EP 1 923 954 A1. Here the base station is equipped with an antenna device which comprises n slots, in which in each case offset vertically to each other dual polarized radiators are arranged, which for example radiate with an alignment that is at a +45° or −45° angle to the horizontal (or the vertical). Via a transmission unit the various slot inputs of the antenna device each have a transmission signal fed to them, with furthermore a receiver unit being connected to the various outputs of the antenna slots. Both the transmission unit and the reception unit have a number of connections for this purpose which are connected with the various connections on the slots of the individual antenna devices.
A MIMO system, for example with two transmission and two reception antennas, is also known from EP 1 643 661 B1.
The object of the present invention is to provide in comparison an improved transceiver module for reception and transmission of mobile telephony signals with multiple transmit-receive branches, which is preferably operated with a radio server on the base station side and which at the same time is preferably positioned in the vicinity of the antenna, for example on an antenna mast or other antenna installation point.
With the solution according to the invention an unexpectedly high variability is created which takes account of different transmission-reception scenarios and different development possibilities and thus allows cost-effective adaptations to be made according to changes in the requirements situation.
The solution according to the invention is characterized, inter alia, in that with the signal conditioning by channel of the transmission signal for the individual channels separate power amplifiers are provided, whereby for the transmission and reception of the signals for each channel or at least for the majority of the channels associated duplex filters are provided. Here the invention assumes that at least four channels are created. The essence of the invention is that a controller device is provided, via which several or all of the power amplifiers, which are connected in several or all channels, can be operated in-phase relation or phase locked to each other. This allows the transmission signals amplified in the channels concerned to be synchronized and thus interconnected with each other and alternatively by means of the multiple duplex filters that are present the individual channels can also be operated separately with various signals. This allows a transmission signal with a higher transmission power to be radiated.
The variability according to the invention as well as the possibility for adaptation according to the invention to various altered operational states, to frequency bands to be transmitted, carrier frequencies and so on, is preferably achieved in that a switching matrix is provided, via which the transmission signals with a specifiable carrier frequency and power amplifiers connected downstream can be fed as required to the various antenna systems. Here, via the switching matrix provided according to the invention, it is possible, for example, to feed to at least four transmission devices (frequency carriers) four separate antenna devices (whereby the four separate antenna systems can also comprise two slots with several dual polarized radiator devices, in which therefore radiators are provided in each of the two antenna slots, which because of their polarization direction or polarization planes being perpendicular to one another are decoupled from one another). It is also possible, however, by means of the switching matrix provided in accordance with the invention, for example with four transmission channels (transmission frequency carriers) to interconnect two, three or all four transmission signals on a single antenna input, whereby on the basis of the interconnection a higher transmission power can be achieved on an output.
According to the invention, however, it is also provided that the phase angles of the signals which are fed to the amplifiers, which are assigned to the individual transmission channels, are coupled in a phase-locked manner.
Thus in the context of the invention it is possible for, for example, two UMTS channels to be inter connected with a virtual doubling of the antenna beam power or for GSM carrier frequencies to be interconnected and fed to a second separate antenna input, etc. As mentioned, it is possible for all four transmission signals to be interconnected on one antenna input or for example for various carrier frequencies for various channels to be provided which feed the transmission signals to the different antenna inputs. In so doing in subsequent upgrades of the mobile telephony base station as a whole, new developments can be taken into account and for example a new channel based on the LTE technology or a number of channels based on the LTE technology implemented.
Generally speaking according to the invention at least one 4-channel version of a transceiver unit is built, which is equipped with a controllable matrix circuit and with which, as mentioned, the power amplifiers provided for the respective transmission branch can be coupled in a phase-locked manner in the transmission channel concerned. With this configuration ultimately different standards can be supported. In addition a previously unanticipated variety of configuration possibilities results. For in the context of the invention various carriers can be transmitted via various branches, whereby two or more identical carriers can be interconnected on a single branch, i.e. on a single antenna input. This transceiver module is preferably created in a remote radio head (RHH) with the at least four transceiver units mentioned, which can also have additional advantages:
Finally, a high bandwidth range of the device according to the invention can be achieved by the duplex filter comprising at least two transmission signal band-pass filters connected in parallel. These can be interconnected differently on the input side. Finally, in order to achieve a higher bandwidth range, the power amplifiers can also combine individual power amplifiers for different frequency ranges connected in parallel.
Other advantages, details and features of the invention can be seen from the following embodiments discussed with the help of drawings. In detail, these show as follows:
a to 14a: schematic representations supplementary to
b: a modified embodiment from
In the embodiment shown, two lines run between the radio server RS in the base station and the remote radio head RRH provided in the vicinity of the antenna, that is to say a main line 7, which preferably comprises a fiber-optic cable 7′. Via this main line 7 as a rule the transmission and reception signals and the control signals for operation of the remote radio head RRH are transmitted. The payload data and control data are also transmitted via the main line 7. In addition, between the radio server RS and the remote radio head RHH a further line 9 also runs, over which, for example, a direct current supply for the components provided in or on the antenna ANT and in the remote radio head RRH is possible
Only in the event that the antenna arrangement shown in
The basic design of the remote radio head RRH can be seen from
As already indicated in
Finally at this point, it is additionally noted in connection with
From the basic structure of the remote radio head RRH according to
On the input side of the RRH, where the main line 7 preferably ending with a fiber-optic cable 7′, is connected, initially a digital platform A that can be configured in different ways is connected, which in the following will also be referred to for short as channel module stage A. In the case shown this stage essentially serves for transmit-receive signal conditioning for each of the four channels K1, K2, K3 and K4 in the embodiment shown.
For connection 7a, i.e. for the connection of the fiber-optic cable 7′ for transmission of the payload and control data, as a connection interface 7a, for example an Ethernet connection (in particular a Giga-Ethernet connection) or for example a CPRI (common Public Radio Interface) or for example an OBSAI (Open Base Station Architecture Initiative) can be used or other suitable interfaces provided for.
For the four transmission and reception channels K1 to K4 for the transmission of the respective transmission signal TX to one of the associated antennas ANT1 to ANT4 in each case a digital-analogue converter DAC and conversely for the reception of a signal RX received from one of the antennas ANT1 to ANT4 an analogue-digital converter ADC can be provided in channel module stage A.
Accordingly the abovementioned digital-analogue converter or analogue-digital converter can be subdivided into channel modules KM1 to KM4. As indicated further in the following, these channel modules can for example be controlled with additionally provided control units, microprocessors, storage elements and so on, via a field-programmable gate array FPGA, which allows conditioning in parallel for the payload and control data. As shown further on, channel modules KM1 to KM4 can have the most varied of configurations, in order to allow via these the most varied of services if necessary (e.g. GSM services, UMTS services, LTE services and so on) to be provided.
The next stage B comprises a mixer and/or amplifier stage B, which ultimately could also be implemented as two separate stages for signal mixing or amplification.
In addition, for each channel an amplifier/mixer module VM1 to VM4 for the channel-dependent transmission path TX with a mixer 19 is provided via which the analogue transmission signals are mixed up to the carrier frequency. Conversely, in the respective reception branch RX of any channel via a corresponding mixer 19′ the reception signal is mixed down.
The TX signal mixed up via the mixer 19 to the carrier transmission frequency is amplified after the mixer 19 via a power amplifier (PA) 21. The signal RX received in the respective mixer-amplifier stage B is in the opposite direction via a low-noise amplifier (LNA) 21′ likewise amplified prior to mixing down in the mixer 19′.
The outputs 23 on the antenna side for the respective transmission signal TX to the mixer-transmitter stage B provided for each channel are connected with corresponding inputs 25 to a switching matrix MX, which is designed as an n/n switching matrix. This switching matrix forms the third stage C.
On the antenna side as the final stage D for each channel K1 to K4 a duplex filter DF1 to DF4 connects to this switching matrix, which on the output 29 for the transmission signal TX on the antenna side in each branch feeds the correspondingly mixed up, amplified and conditioned transmission signal to a first input 31 of a respective duplex filter DF1 to DF4 and at the antenna connection 32 via the transmit-receive line 11a is fed the associated antenna system. The connection 32 from the first duplex filter DF1 is for example connected via the transmit-receive line 11a with the first antenna system ANT1. Accordingly the duplex filters of the other channels K2 to K4 are connected with the other antennas ANT2 to ANT4 via the respective antenna lines 11b to 11d.
Alternatively the RX signal received via the respective antenna system is fed via the transmit-receive line 11a, 11b, 11c or 11d concerned to the respective connection 32 of the respectively assigned duplex filters DF1, DF2, DF3 or DF4 and by virtue of the band-pass filter is then as a reception signal RX via the connection 31′ fed to the matrix connection 29′, switched-through via the reversing matrix MX, and in fact to the radio server-side connection 25′, where the RS reception signal concerned is fed to the respective amplifier-mixer stage B, in order in the amplifier provided there 21′ to be amplified and mixed down in the subsequent mixer 19′.
From this structure it can already be seen that that the RX signal received from each antenna system ANT1, ANT2, ANT3 or ANT4 is fed via the respective duplex filter DF1, DF2, DF3 or DF4 in duplex filter stage D separately through the switching matrix or past this to the respective separately assigned amplifier (LNA amplifier) 21′ with the following stage 19, in order then in the ADV converter of the respective channel in the channel module stage A to be digitized and passed via the main line 7 to the radio server RS.
In order to better understand the multitude of different switching possibilities for the operation of the antenna system described, in the following, using
From
In the mixer-amplifier stage B shown in
For the in-phase control of the individual power amplifiers 21 in channels K1 to K4 from the transmission signal TX by means of a coupler device KE a signal is decoupled, on the basis of which the in-phase control of all power amplifiers 21 in the other and preferably all channel stages is carried out. In the embodiment shown the coupler device KE ultimately comprises four separate couplers, which are assigned to the individual power amplifiers PA. Furthermore from the transmission signal a signal for linearization and phase coupling can be decoupled, which is fed via a control unit 33 for phase calibration as a stage A feedback signal. In addition this decoupling mechanism, for the respective transmission signal, in each of the four transmission paths in the embodiment shown can also be used for linearization of the power amplifier. This decoupling mechanism can be constructed in such a way that the respective transmission signal is decoupled from the respective output of the amplifier 21 or the antenna-side output of the duplex filter 32 and in rapid sequential order is compared with a reference signal for in-phase control of the power amplifiers, and furthermore the same mechanism can be simultaneously used for linearization of the transmission signal. However, the phase correction can be carried out by a coupler KE that works not sequentially but in parallel, for example a Wilkinson coupler. In this case, however, for the various channels separate test signals must be used. In both cases a simplification of the overall structure results, since the four transceiver units in the embodiment shown make shared use of the signal conditioning to a large extent.
In certain cases it may be helpful to carry out the linearization and/or phase calibration in such a way that a signal is decoupled from the respective transmission paths after the duplex filters DF1 to DF4 or from the transmission signal TX, to which end the optional decoupling path 121 is provided for the purpose, which in turn in the embodiment shown leads to the control unit 121.
With the help of
In the control unit KE it can also be seen that here again a microprocessor μC-1 is provided, a mixer stage 141, a low-pass TP and a phase-locked loop, thus a phase correction loop, in order to adjust the phase angle and thus the associated frequency of a changeable oscillator and thus of the mixer 141. With this control unit 121, therefore, ultimately the antenna can be precisely calibrated, since the phase angle is precisely adjusted.
In the process
In the following, using various embodiments, an explanation is now provided of how the structure according to the invention can be used in order to use the antenna device in particular for a mobile telephony system for varying requirements.
In so doing the various scenarios discussed in the following are also listed using the tabular overview attached in the annex, in which various configuration possibilities are described.
In the course of this
This therefore allows a particular large range to be achieved by the transmission signal.
In this, as in the subsequent embodiments, it is assumed that the amplifier 21 in the first channel and in the second channel in each case generates a transmission power of, for example, 25 Watts, whereas the amplifier 21 for the third channel K3 and the fourth channel K4 only has a transmission power of 15 Watt in each case. By interconnecting all transmission signals a GSM transmission signal of 80 Watts thus results and a greater transmission range is achieved. The corresponding data for the channels or slots 1 to 4 are shown in the abovementioned attached tabular overview under configuration A1.
This interconnection of the four transmission signals is possible because the phase angles of the four amplifiers 21 are synchronized. The decoupling of a feedback signal necessary for the linearization of the amplifiers is thereby simultaneously also used for phase correction.
The configuration A1 in question, as also all the other configurations that are described in the following plus other configurations which are not explained using the drawings and which are possible within the context of the invention, are for example shown in the tabular overview attached as an annex, and in fact with all the important individual data for the operation of the respective configuration.
Already from the embodiment according to
In a departure from the embodiment shown a configuration A2 (listed only in the attached table and not in the drawings) could also be created, in which for example the outputs 29a and 29b for the first and second channels and outputs 29c and 29d for the third and fourth channels are interconnected so that via the transmit-receive line 11a the antenna slot or the antenna system ANT1 is fed a GSM standard signal at a first carrier frequency f1 with a strength of for example 50 Watts and the second antenna system ANT3 a GSM signal at a second carrier frequency f2 with a total power of 30 Watts.
With the help of
Whereas in previously known RRHs several carriers are transmitted with different frequencies via the same power amplifier (PA), whereby the requirements on the power amplifier (PA) are considerably increased (for it must operate as a multi-carrier power amplifier), in the context of the present invention the advantage arises that in each case only one GSM carrier has to be amplified by an amplifier, by which means the total effort, in particular the intermodulation requirements, are considerably reduced. Compared with the known combination of several transmission amplifiers via passive combiners (hybrid combiners) the solution according to the invention offers the advantage of a virtually loss-free interconnection, while the combiner solution loses at least 3 dB.
Here also, as in all the examples shown, the signals received RX are fed over the four transmit-receive lines 11a to 11d separately from one another via the duplex filter to the amplifier stages LNA provided for in the individual channels K1 to K4, i.e. the amplifier stages 21′ and mixers 19′, in order then to be fed via the four separate analogue-digital converters and the subsequent common signal transmission line 7 to the remote server.
The fact that the reception signals are always conditioned separately for each channel and then transmitted together via the man line 7, applies for all the other embodiments discussed in the following. However, it is also conceivable that already in this transceiver unit an in-phase summation of the various RX signals is carried out, in order thereby to generated one or more resultant radiation diagrams of the antenna slots and to transmit these summed signals to the RS. Further signal conditionings in the RRH are conceivable.
By way of deviation from the embodiment according to
With the help of
With this variant in the first and second channels K1 and K2 at a common carrier frequency a GSM standard signal is conditioned and transmitted. In the third and fourth channels K3 and K4 on a common carrier frequency a UMTS signal is conditioned and transmitted. In this way with the selection indicated of the amplifier concerned, a transmission signals can be transmitted in a common channel according to the GSM standard at 50 Watts in order to achieve an increased range in this standard and a transmission signal with 30 Watts in a further channel according to the UMTS standard, likewise with an increase in the range compared with an individual channel. Here the UMTS signal is sent according to the W-CDMA method (Wideband Code Division Multiple Access), in which the transmission signal has a marked spread, so that it occupies a larger bandwidth and thus is less susceptible to faults from narrow-band interference pulses. In addition in this way the transmission power per Hertz can be reduced. As a result a greater bandwidth of, for example, 5 MHz results.
With the help of the attached table, by way of example configurations B2, B3 and B4 are also shown, whereby according to configuration B2 for example the first two GSM channels (which each have a 25-Watts amplifier 21) are interconnected, resulting in a single GSM channel with a power of 50 Watts with the achievement of an increased transmission range. The two UMTS channels K3 and K4 are operated separately, whereby in this embodiment they then result in two UMTS carrier frequencies each with 15 Watt power.
In configuration B3, by way of example the two UMTS channels K3 and K4 are interconnected, which thus results in a single UMTS carrier with 30 Watts, whereas the two GSM channels K1 and K2 radiate two separate carriers TX1 and TX2 each with 25 Watts.
In configuration B4, similar to configuration A3, all channels are separately operated so an overlaying and combining of the individual transmission signals is not carried out.
In the following reference is made to
Further possible configurations B6 to B8 using a GSM channel and three UMTS channels can be inferred from the attached table.
According to the embodiment according to
Here also further different configurations are possible, with which, for example, two groups of two or at least one group of two plus two individual channels or one group of three channels can be interconnected with a remaining UMTS channel. By differing selection of the channels in the process different signal powers for the UMTS signal can also be achieved, for, as premised in the embodiment shown, the amplifiers 21 work with different powers. In the process all amplifiers can have different powers, so that two amplifiers do not necessarily have to have a high power of for example 25 Watts and two amplifiers a comparatively lower power of for example 15 Watts.
With the help of
In
In the following further configurations with an expansion in capacity according to the LTE standard are dealt with.
With the help of
With the help of
With this embodiment the LTE standard is the only standard which allows a variable bandwidth definition.
In
In the attached table further configurations C4 to C6 are given by way of example, without ultimately showing all variants.
The structure of the remote radio head RRH described with its large variation range, as basically it can be used, is the result above all of the fact that the amplifier 21 is designed for the amplification of the transmission signal as, however, the amplifier 21′ is for amplification of the reception signal. The amplifiers are preferably designed in such a way that they can, for example, be used in a frequency range of 1,700 MHz to 2,700 MHz. If the amplifiers could be designed with an even larger broadband range, for example from 800 MHz or 900 MHz to 2,700 MHz, then transmission in the lower frequency ranges could also be implemented. In practice, however, a design for the range from 1,700 MHz to 2,700 MHz can be envisaged, whereby in this frequency range the transmissions according to the GSM, UMTS or LTE methods are feasible.
If with regard to the broadband range of the duplex filters DF1 to DF4 used problems were to arise, then—as shown with the help of a variant according to FIG. 15—an improvement can be achieved in that the duplex filter devices DF1 to DF4, here preferably in the form of band-pass filters, are arranged for the individual frequency bands with individual band filters connected in parallel for the transmission signal TX or for the reception signal RX. To this end, according to the embodiment according to
The ideal is a duplex filter with frequency trimming which adjusts or is adjusted to the transmission and reception frequency used in the channel. Because of the high intermodulation requirements essentially only mechanical components whose frequency can be trimmed, such as for example NEMS, piezo elements or motor drives, are considered for this.
The PA power amplifier 21 for the transmission signals and the reception amplifier 21′ (LNA amplifier) for the reception signals are preferably designed with such a broadband range that they cover the entire frequency range necessary.
The digital platform according to channel-module stage A referred to in particular in connection with
Finally, reference is also made to a further modification according to
With this variant also, similar to in
The power amplifiers 21 (PA amplifiers) are constructed separately for the individual frequency bands. The reception amplifiers (LNA amplifiers) 19′ are designed with a broadband range and cover the entire required frequency range.
The digital platform according to the channel module stage A can at the four outputs/inputs of the individual slots of various mobile telephony standards, make available frequencies (and variable bandwidths) in the entire frequency range required, just as in the embodiment according to
Since for the transmission signals TX separate power amplifiers 21 are used for the various frequency bands, according to a further variant the digital platform (channel module stage A) for the transmission path can make available separate outputs for each individual frequency band, which are then transmitted in parallel.
Therefore the most varied of embodiments have been described which allow a highly variable operation of the transceiver unit (RRH). The variability is the result of the different configuration possibilities in the digital platform A, whereby here the most varied of mobile telephony standards, such as GSM, UMTS, LTE and so on, can be achieved, and in fact in any composition. Above all as a result of the switching matrix arranged in the transmission direction prior to the duplex filters DF it is possible to achieve the high variability, since here the most varied composition of the transmission signals is possible where necessary. In the switching matrix the outputs from the transmission amplifier can be switched through directly to the duplex filter or in the case of the bringing together of amplifier outputs normally one or more passive combiners (normally Wilkinson combiners) are interconnected, so that in this way a resultant transmission amplifier with one or more outputs emerges. The combiners, preferably Wilkinson combiners or hybrid combiners, perform the task of decoupling the amplifier outputs and adaptation at the interconnection point.
The overall structure is such that preferably an operation of the transceiver module (RRH) for various standardized mobile telephony frequency ranges is possible, preferably for those whose ratio between top and bottom frequencies is a maximum of 2:1, so that in this way simultaneous operation in up to three mobile telephony frequency ranges is possible, whereby each channel is preferably operated in a maximum of one frequency band only.
Finally, it is also possible to operate the RRH in the various channels in such a way that individual amplifiers of a channel work in non-linearized mode, for example AB- or B-mode. In this way linear and non-linear amplified signals will be combined at the antenna. Thus high levels of efficiency of amplifiers in non-linear mode can be taken advantage of. Such an amplifier will normally be designed to be switchable, so that it can work in a linearized or non-linearized mode.
The linearized or non-linearized mode is achieved by a shifting or switching of the operating point in the end stage.
In summary, therefore, it can be established that in the context of the device according to the invention, it is possible
With the help of the embodiments portrayed it has been shown that in the context of the invention not only a high variability in terms of the device for transmission and reception of signals, in particular for the area of mobile telephony, can be ensured, but that furthermore optimum adaptation or preparatory set-up is possible, in order to operate the entire system in an unknown manner in the broadband range, for example in that:
Finally, in the context of the various embodiments it has also been explained how the device for transmission and reception of the corresponding signals, in particular for the mobile telephony area, allows an in-phase radiation of the various TX signals, in order thereby to generate a resultant radiation diagram, whereby the filter stages on the antenna side can be controlled by channel via the power amplifier assigned or preferably a switching matrix is provided in between these, in order to be able to operate the system as a whole differently. In an equivalent way a radiation forming for the reception case can also be carried out.
On the basis of the device structure illustrated a corresponding method also thereby emerges of how this device is operated, and how therefore in the individual channels the transmission signals can be amplified, coupled in-phase or phase-locked and finally summated in corresponding operating modes, in order, for certain standards, to allow an expansion of capacity or an increased range of the transmission signal. This being the case, in connection with the device illustrated, a corresponding method for operation of such a device is also obvious in its entirety.
