RU2563028C2 - Method and device of generating at least one output signal - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to communication engineering and can be used in wireless communication systems. Described method of generating at least one output signal for a receiving unit (56), which includes receiving at least a first input signal through at least a first antenna (44) and receiving at least a second signal through at least a second antenna, subsequently preprocessing each input signal, combining the preprocessed input signals with each other by calculating and outputting at least one generated output signal to the receiving unit (56) through a connection (54).

EFFECT: high transmission channel throughput.

13 cl, 4 dwg

Description

The present invention relates to a method and apparatus for obtaining at least one output signal for a receiver.

High-quality automotive frequency-modulated broadcasting reception systems use several antennas to improve reception compared to systems that have only one antenna. The advantage of using multiple antennas is the ability to switch between antennas and then transmit to the receiver the input signal of the selected antenna through a high-frequency signal. This process is called diversity diversity switching.

From the publication DE 102006039357 A1 it is known that there is the possibility of switching between the signals of individual physical antennas and the signal obtained by adding at least two real analog signals. To do this, the vehicles usually place antenna elements on the rear window and connect them with short, several centimeters long, wires to the antenna switch. In the antenna switch, only one antenna signal is always selected. After that, the entire reception range of one of the antennas becomes available to the radio due to the high-frequency cable, made, as a rule, in the form of a coaxial cable. In the radio, subsequent signal processing is carried out. At the same time, in the radio receiver, from the entire reception range, the necessary frequency is extracted with the filter, which is converted to an intermediate frequency, filtered again and processed when the user selects the reception frequency by tuning the radio receiver. For the switch to make a decision about which of the available antenna signals should be selected, it needs information about the frequency selected in this range of the radio receiver. For this purpose, an intermediate-frequency signal generated in a radio receiver enters the antenna switch via a high-frequency cable for subsequent processing.

In the publication DE 102006006266 A1, it is described that signals are received from the receiver to the switch via a separate channel, which under special reception conditions prevent switching.

In yet another method, from two signals obtained by amplifying and / or filtering two different linearly independent input signals received by the antennas, one new signal is calculated by means of a complex linear combination.

Further, systems are known for performing phase diversity reception and differing from systems in which diversity diversity switching is used. In phase diversity reception systems, two or more input signals received by the antennas are combined after digital processing, and the complex linear combination coefficients are continuously consistent with the reception conditions.

On the other hand, diversity diversity systems with diversity diversity branches selectively select between multiple input signals, even in cases where individual of these input signals are generated by adding the input signals of two antennas. When switching there is interference. In addition, diversity diversity switching systems including a separate antenna switch receive an intermediate frequency signal from the car radio (headunit) containing the information required for switching.

The method that implements phase diversity reception and is known from DE 102004062000 A1 uses a mixing stage connected to the antennas, in which the input signal of one of the antennas is converted into an input signal of a different frequency range, so that after addition the input signals received from both antennas are transmitted over a high-frequency cable with different mid frequencies. The disadvantage of this method is the need to include in the transmission path of the input signals of the receiving system two additional schemes for combining the input signals. In addition, frequency conversion should be carried out over the entire width of the reception range, as a result of which additional mixers are subjected to dynamic effects throughout this range. Due to the limited dynamic properties of these mixers and the cascading of mixing processes, which helps to increase noise and reduce intermodulation characteristics throughout the signal transmission path, such a system is inferior in performance to a system with a digital directional antenna (DDA - from the English Digital Direction Antenna), having two antenna channels. Another disadvantage of this system is the appearance of a phase error in the mixing processes. This error has to be compensated for using phase diversity reception algorithms, which can also lead to a decrease in output power.

From publication US 2009/0298453 A1, which discloses the closest analogue of the invention, a system for combining several frequency-modulated signals in a receiver is known, the known system comprising two antennas and one analog-to-digital converter (ADC) for each antenna. The transmission paths of the received signals for the ADC are digital and are located inside the signal processor.

Based on the above-described prior art, the present invention provides a method and apparatus described in the independent claims. Particular embodiments of the invention are given in the dependent claims and are presented in the description.

Proposed in the invention a method of obtaining at least one output signal for a receiving unit, includes:

- receiving at least one first input signal by means of at least one first antenna and receiving at least one second input signal by means of at least one second antenna,

- pre-processing of the input signals by digitizing them, performed separately for each input signal,

- combining pre-processed input signals with each other with the generation of at least one output signal,

- issuing at least one generated output signal to the receiving unit by means of a connection,

moreover, the receiving device is supplied with electrical energy by phantom power from the receiving unit through the aforementioned connection.

Proposed in the invention a device for receiving at least one output signal for a receiving unit contains at least two antennas and a receiving device, and the receiving device is configured to:

- receiving from at least one first antenna of at least one first input signal and from at least one second antenna of at least one second input signal,

- pre-processing of the input signals by digitizing them, performed separately for each input signal,

- combining pre-processed input signals with each other with generating at least one output signal,

- issuing to the receiving unit at least one generated output signal by means of a connection,

- receiving electrical energy from the receiving unit by phantom power through the aforementioned connection.

The technical results achieved by the implementation of the invention are to reduce the required hardware by using only one connection, in particular a high-frequency cable, between the receiving device and the receiving unit (radio) to transmit the output signal in one direction and supply power in the other direction, and also the fact that by using only one high-frequency cable it is possible to provide high-speed data transmission, as well as compatibility of the cable bundle with other their receivers.

The invention makes it possible to realize phase diversity by means of only one high-frequency channel, namely, a high-frequency cable, which serves to connect the receiving device to the receiving unit, made, for example, in the form of a radio receiver. Therefore, in a vehicle, you can use a DDA device, designed in the form of a space-oriented digital receiving antenna, or the corresponding system, the cost of which will not be as high as in the case of a system with two high-frequency cables.

In accordance with the invention, the input signals are pre-processed by at least two antennas by digitalization, i.e. digitization. During pre-processing, each input signal can be filtered, amplified and / or digitized. The frequency of the input signal can also be converted. Typically, input signals are combined by computation with at least one computational operation to produce at least one output signal. In this case, during the calculation, multiplication by complex coefficients and addition of at least two independent input inputs, i.e. received signals. The formation of such a linear combination of two input signals received in the same receiving channel and subjected to pre-processing takes place in the antenna system (usually in the receiving device), and not in the radio receiver, as provided for in the systems known from the prior art.

Formed from the input signals, at least one output signal, or an antenna signal, can be transmitted for further processing to a radio receiver (head unit), which acts as a receiving unit by means of a connection made, for example, in the form of a cable. Typically, two or more output signals or antenna signals can be obtained. Thereby, a DDA device can be realized by only one cable, which can be made in the form of a high-frequency cable. Moreover, by using only one high-frequency cable, it is possible to provide high-speed data transfer, as well as compatibility of the cable bundle with other receiving devices.

An antenna system or antenna device with DDA signal processing is called a DDA tuner, or switch. The unit in which such signal processing is performed may also be referred to as a DDA antenna. Moreover, the antenna device includes at least two antennas, a short supply line and a receiving device made in the form of a switch.

In this case, the high-frequency cable in accordance with the invention is used to supply power to the receiving device or DDA tuner, and can also be used for digital control of the receiving device. To supply energy to the high-frequency cable, a constant voltage is supplied, which is then transmitted to the DDA tuner by the so-called phantom power. In one of the possible embodiments for controlling the DDA tuner, it is provided to use different carrier frequencies to output at least one digital output signal of the DDA tuner to the radio receiver or head unit and a digital control signal from the head unit to the DDA tuner, as well as to implement digital DDA antenna control

An embodiment of the invention is possible involving the use of a receiving module with a high degree of integration in the form of a receiving circuit in the receiver, and two parallel signal transmission paths. Due to this, only a single pre-processing of the mixer control signal is required, as well as only one phase-locked loop (PLL). The method can be implemented in relation to direct and / or indirect removal of input signals.

In another embodiment of the invention, the antenna amplifier and the input stage of each input signal transmission path can be combined, or combined, which allows only one automatic gain control (AGC) circuitry, which is usually integrated in the receiver receiving module, to be implemented.

At least one output signal may also be generated by modulating the carrier with pre-processed input signals and / or by combining the pre-processed input signals in one channel.

In addition, amplitude modulation broadcasting implemented within the framework of this method can be implemented by generating a frequency of at least one output signal or a mixed signal based on a fixed local oscillator frequency or a reference frequency, depending on the conditions, by division and / or multiplying the frequency of at least one input signal, typically the frequencies of the input signals. In the case of such at least one output signal, by means of a mixer of one of the signal transmission paths, conversion to the corresponding intermediate frequency and, if necessary, filtering of some part of the frequencies of the broadcasting range with amplitude modulation is carried out. The subsequent process involves not generating a linear combination of input signals from signal transmission paths, usually pre-processed by digitization, but transmitting both digitized signals of intermediate frequency via a connecting cable to the receiving unit and their subsequent processing there. The resulting possibility of simultaneously receiving frequency-modulated and amplitude-modulated input signals allows, for example, administration of a list of radio stations in the background.

An embodiment of the invention is also possible, which involves the use of at least two independent receiving modules until a linear combination is formed, in which a linear combination is not generated from time to time, while one receiving module remains at the input signal frequency and provides an input signal for generating an audio signal while the second module simultaneously searches for the best alternative frequencies.

As a signal, interfaced with a receiving device, made, as a rule, in the form of a DDA tuner, you can also use a signal that is subjected to further processing, for example an audio signal. In this case, the input signal is the source of the audio signal for the car radio, or the head unit of the stereo system.

Since the input signals are digitized, in the method of the invention, the receiving device is different from the receiver located somewhere in the vehicle, receiving input signals from two or more antennas, combining them in an analog form and generating an audio signal.

The described device is intended to perform all the steps of the presented method. Moreover, the individual steps of this method can also be performed by the individual components of the device. Further, the functions of the device or the individual components of the device can be transformed in the process. In addition, it is possible to implement the stages of the method as functions of the individual components of the device or device as a whole.

Other advantages and embodiments of the present invention are presented in the description below, illustrated by the attached drawings.

It should be borne in mind that the distinguishing features mentioned above and described below can be used in the framework of the present invention not only in the presented, but also in other combinations or separately.

The drawings show:

in FIG. 1 is a schematic representation of a first embodiment of a prior art device,

in FIG. 2 is a schematic illustration of a second embodiment of a prior art device,

in FIG. 3 is a schematic illustration of a device according to a first embodiment of the present invention,

in FIG. 4 is a schematic illustration of a device according to a second embodiment of the present invention.

The following is a detailed description of embodiments of the invention shown in the schematic representation in the drawings.

Descriptions of the drawings are given in conjunction with cross-references, and the same components have the same reference symbols.

In FIG. 1 is a schematic representation of a first embodiment of a prior art device 2 comprising an antenna system 4 with two antennas 6, 8 located in a rear window of a vehicle. For each antenna 6, 8, one removal unit 10, 12 of the antenna input signal is provided. These pickup units 10, 12 are connected to the antenna switch 14. The antenna switch 14 is connected to the car radio 20, which can also be called the head unit, through the first channel 16, designed to transmit an analog high-frequency (RF) signal, and the second separate channel 18, intended to transmit an intermediate frequency (IF) signal.

The implementation of the method of diversity reception with switching diversity branches is carried out in this case by establishing communication with two antennas by means of pickup units 10, 12, antenna switch 14 and channels 16, 18 made in the form of high-frequency cables between the antenna switch 14 and the car radio 20. In this case, During the reception process, switching between antennas 6, 8 takes place, and the passage of the IF and RF signals is also possible only on one channel 16, 18. In this case, the appropriate frequencies must be provided in the circuit Different separation filters.

The disadvantage of this method of diversity reception with switching branches of the diversity is that at each point in time you can use the input signal of only one antenna, which limits the receiving ability of device 2. Another disadvantage is that switching between antennas 6, 8 is the cause of interference.

In the known device 24, a schematic representation of which is shown in FIG. 2 as a second example, basically the same components are used as the device 2, but there is no antenna switch 14. Instead, there is provided a DDA car radio 28 connected via the first channel 16 and the first input signal pick-up unit 10 with the first antenna 6 and through the second channel 18 and the second input unit 12 of the input signal with the second antenna 8.

In the method implemented by the second device 24, two receiving systems are used, consisting of antennas 6, 8 and acquisition units 10, 12 of the antenna input signals, in which the new signal is calculated as a complex linear combination. In this case, by appropriate selection of individual complex coefficients, the quality of the resulting signal can be significantly improved in comparison with the individual input signals taken from antennas 6, 8. In this way, among other things, it is possible to almost completely suppress interference arising from the reception of input signals coming into this area from different directions. Moreover, in areas with a low level of reception, it is possible to increase the output power by appropriately adding both input signals. Corresponding devices or systems 24 have been on the market since about 2002 and are commonly referred to as DDA systems, or phase diversity reception systems. In these systems, the two input signals of the antennas 6, 8 enter the receiver, made in the form of a car DDA radio 28 through two separate high-frequency coaxial cables used as channels 16, 18. In the car DDA radio 28, these input signals are amplified, filtered, converted into intermediate frequency signals, digitized and subsequently digitally processed. In this case, three or more input antenna signals can also be processed.

The disadvantage of the DDA device 24 is that it requires two high-frequency cable channels. In contrast, simple car radios with only one antenna or diversity diversity circuit switched system cost only one high-frequency channel between them and the antenna. This disadvantage of the DDA device 24 is reflected in the appreciation of the system used in the vehicle.

An apparatus 40 according to a first embodiment of the present invention, a schematic representation of which is shown in FIG. 3, comprises an antenna system 42 with at least one first antenna 44 and at least one second antenna 46, which are located at some distance from each other. Moreover, each antenna 44, 46 is connected to the pickup unit 48, 50 received by it, i.e. input signals. In turn, the acquisition units 48, 50 are connected to a receiver 52, which may also be referred to as a DDA tuner or a receiver with a digital directional antenna. The receiving device 52 is connected to the receiving unit 56, made in this case in the form of a car radio or head unit, through only one connection 54 made in the form of a cable or a conductive line.

In this device 40, the receiving device 52 receives the first input signal from the first antenna 44 through the first pickup unit 48 and the second input signal from the second antenna 46 through the second pickup unit 50. In this case, the receiving device 52 pre-processes each of the input signals separately . Then, the pre-processed input signals are combined with each other through a computational operation, as a result of which at least one output signal is generated. Therefore, by implementing the phase diversity reception method in the receiver 52, at least one output signal, which can also be called an antenna signal, is obtained from the input signals. Only one connection 54 is required to provide at least one output signal, which can also be called an antenna signal, to a receiving unit 56.

In FIG. 4 is a schematic illustration of a device 60 according to a second embodiment of the present invention. This device 60 contains at least two spatially separated antennas 62, 64 connected to a receiving device 66, made in the form of a DDA tuner. The input signals received by the antennas 62, 64, synchronously arriving at them from the same radio station at the same frequency, are transmitted to the receiving device 66. Inside the receiving device 66, a module 68 is provided for subsequent processing of the input signals. A separate preprocessing circuit 70 is provided for each input signal in this module 68. These circuits 70 pre-process each input signal received by each antenna 62, 64 individually, during which each input signal is usually filtered and / or amplified. In addition, frequency conversion of each of the input signals and / or digitization of these input signals may be provided.

Next, the signal processing in module 68 continues to computational circuit 72, in which a combination of pre-processed input signals with each other is performed. The process of combining input signals occurring in computing circuit 72 typically involves generating a linear combination of input signals that have already been pre-processed. As an alternative or addition to computational circuit 72, division and / or multiplication of pre-processed input signals may be performed. The processing steps performed at receiver 66 also include, but are not limited to, analog-to-digital conversion, calculation of complex DDA coefficients, and addition of the digital signals thus obtained.

The device 60 shown in FIG. 4 also includes a receiving unit 74, which may be in the form of a car radio or head unit and located, for example, in the center console of the vehicle. The receiving device 66 and the receiving unit 74 are connected to each other by means of a connection 76 made in the form of a cable. At least one output signal resulting from the subsequent processing of the pre-processed input signals is transmitted via cable 76 from the receiver 66 to the receiver unit 74. At least one output signal received by the receiver unit 74, typically a digital signal, is subjected to if necessary, additional processing in the circuit 78 located inside the receiving unit 74, and is issued in the form of an audio signal.

Connection 76 provides two-way communication between the receiver 66 and the receiver 74. Through the connection 76, made in the form of a cable, the reception control signals or the tuner can be received from the receiver 74 by the receiver 66. In addition, through the connection 76 is the energy supply of the receiving node 66.

Reception control signals in this embodiment may include tuning information, including information about the selected reception range and alternative frequencies tested, transmitted as part of the RDS strategy (abbreviation of the term Radio Data System is a standard for transmitting information messages on broadcasting channels), which This embodiment is implemented in the controller of the receiving unit 74, made in the form of a head unit. However, it is also possible to implement the RDS strategy in the receiver 66, made in the form of a DDA tuner.

Claims (13)

1. A method of obtaining at least one output signal for a receiving unit (56, 74), including:
- receiving at least one first input signal through at least one first antenna (44, 62) and receiving at least one second input signal through at least one second antenna (46, 64),
- pre-processing of the input signals by digitizing them, performed separately for each input signal,
- combining pre-processed input signals with each other with the generation of at least one output signal,
- issuing at least one generated output signal to the receiving unit (56, 74) through the connection (54, 76),
moreover, the receiving device (52, 66) is supplied with electric energy by phantom power from the receiving unit (56, 74) through the aforementioned connection (54, 76). 2. The method according to p. 1, in which the combination of pre-processed input signals with the generation of at least one output signal is carried out by means of a computational circuit (72). 3. The method according to p. 2, in which the generation of at least one output signal is carried out in a computational circuit (72) by forming a linear combination of pre-processed input signals. 4. The method of claim 1, wherein the at least one output signal is generated based on a fixed local oscillator frequency or a reference frequency by division and multiplication. 5. The method of claim 1, wherein the at least two pre-processed input signals modulate at least two carrier signals from which at least one output signal is generated. 6. The method according to claim 1, wherein the pre-processed input signals are combined in one channel, generating at least one output signal. 7. The method of claim 1, wherein pre-processing the at least one input signal further includes filtering, amplifying, and / or converting the frequency of the at least one input signal. 8. The method according to p. 1, carried out in relation to input signals received in the same receive channel and / or with the same receive frequency. 9. The method according to one of the preceding paragraphs, in which, by connecting (54, 76), the receiving device (52, 66) is controlled by the receiving unit (56, 74). 10. A device for receiving at least one output signal for a receiving unit (56, 74), comprising at least two antennas (44, 46, 62, 64) and a receiving device (52, 66), the receiving device (52, 66) is configured to:
- receiving from at least one first antenna (44, 62) of at least one first input signal and from at least one second antenna (46, 64) of at least one second input signal,
- pre-processing of the input signals by digitizing them, performed separately for each input signal,
- combining pre-processed input signals with each other with generating at least one output signal,
- issuing to the receiving unit (56, 74) at least one generated output signal through the connection (54, 76),
- receiving electrical energy from the receiving unit (56, 74) by phantom power through the aforementioned connection (54, 76). 11. The device according to p. 10, in which the connection (54, 76) is made in the form of a cable, through which the receiving device (52, 66) is connected to the receiving unit (56, 74), made in the form of a radio receiver. 12. The device according to p. 10 or 11, in which the receiving device (52, 66) contains a receiving module with a high degree of integration, made in the form of a receiving circuit, as well as at least two parallel transmission paths of the input signals. 13. The device according to p. 10 or 11, in which the receiving device (52, 66) contains a receiving module configured to search for a second, alternative, frequency for the input signal received at the first frequency.

Images