DE3929596A1 - Controlling demodulators for EM signals - using combination of code stored in transmitted signal and mathematical model stored in microprocessor - Google Patents

Abstract

The programme content detection device is in two stages. One stage (A) comprises an a-d converter (1), a memory (3), a timer circuit (4), a clock generator (5), a band-pass filter (6), a databus (7), and a microprocessor (8). The other part (B) is the classification and control stage. The arrangement examines the signal transmitted, which contains a code, and enters it in a mathematical model of the power spectrum in the frequency domain. A differential power spectrum is then obtained which is converted to digital form. Pref. the mathematical model is held in a microcomputer. USE - Radio and t.v. equipment, esp. video recorder for response to selected programme without being rigidly set to time.

Description

The invention relates to a method according to the preamble of claim 1 and claim 2. Such an inventions So far, manure is not known from publications.

With the introduction of repetitive interruptions of radio and television broadcasts or through a targeted yourself repetitive signal a situation has arisen, the one Hiding freely selectable program parts as interests makes sant appear. Because of the existing devices it only possible the state of the reception or re corder devices via a variable specified by the transmitter control signal. The individual owner of an Em pfangs- or recorder device had either this Control signals, certain working hours of the device or the Use operating heads on the device if it has the Control the state of the device depending on the time and situation wanted.

The invention lies in the knowledge of these facts Task based, using certain, from a Mi Functional elements shown in a crocomputer, the selection certain signals from a steadily flowing signal flow enable. This task is there according to the invention solved by that a device according to the characteristic Features of claim 2 by means of one that characterizes Features of claim 1 containing data processing pro gramms, controls that the generic measures ent be expanded accordingly.

In particular, two specially designed microcompu systems stored in a permanent memory put program controlled that according to the procedure signals received by a receiving part of the different channels after digitization into one Ring buffer in 6 blocks with a frequency band length corresponds to a time interval of 2 seconds to get out of this after the transition to the frequency level from the perform a power spectrum calculation in the first sub-spectrum to lead.

According to the program, this range of services is based on a be voted as the initial frequency value of a signal  Frequency value with significantly above the noise background lying amplitude value searched.

If this amplitude is present, the partial spectrum and the subsequent subspectrums of a more precise Be subjected to evaluation. If this is not the case, it will next sub-spectrum again this amplitude detection un educated and continued successively until an initial fre reference value is present in the sub-spectra.

If this is available, the range of services with a higher accuracy, i.e. the resolution of 2 Hz is calculated and according to the program by moving the y-axis of the power spectrum the positive amount thereof forms.

After that, the local averages of this spectrum put a compensation function that the new zero line of the here forms the so-called differential power spectrum.

This is the difference, performance spectrum minus compensation function calculates which are necessary for the classification Features components included.

After this spectrum became the basis of the actual class sification has been defined, have been used advantageously Design of the invention all positive values on the value One set all others to zero, which results in a new picture of the spectrum of the so-called 01 spectrum arises.

This special spectral representation is the basis of the Classification process used according to the procedure.

For the classification of the signal, the 01 spectrum in passed a further process step in which the pattern of the signal compared to a stored learning pattern and is assigned to a specific signal if necessary. To The classification that has been made will then be saved to it th signal assigned control signal, which a any device, preferably a radio or video device in a defined operating state.

In an advantageous embodiment of the invention, the learning pattern the control unit according to claim 1 and claim 2 itself taught, i.e. the system can be switched in one Working mode: "learning phase" can be switched, which firstly the learning patterns can be individually predefined and systembe  due to the necessary processing time of signals from the system become meaningless since that System always performs the same processes, regardless of whether it is in the Learning mode or operating mode. Permanent storage the learned pattern is guaranteed by a battery. In the following, an embodiment is made with reference to drawings game of the device according to the invention explained.  

The drawing shows in

Fig. 1 in a simplified block diagram, the device according to the Invention with all functional elements.

The real circuit diagram shown in FIG. 1 shows the device according to the invention, which is composed of the receiving part for the electromagnetic signals emitted by a transmitter and the processing stage A. This receiving part 1 is coupled to a functional stage A, which has at least the functional elements: bandpass 6 , analog / digital converter 2 , a memory 1 , part 3 , a timer 1 , part 4 , a clock generator 1 , part 5 , and a data bus 7 to the following functional level B.

In this function level A, reception takes place, the one emitted by a preselectable station electromagnetic signals, the permanent storage of the digitized signal width of the transmitter in marked Sections, preferably in 8 blocks of 2048 in 12 bits solved data blocks in a memory, the memory was constituted in a ring, so that after the 8th block the first block was overwritten again becomes.

Function level B has at least the functional elements microprocessor 2 , part 14 , data bus 2 , part 21 , timer 2 , part 9 , clock generator 2 , part 10 , memory of the power spectrum 2 , part 11 , for the found compensation curve 3 , part 12 , for the 01 spectrum 4 , part 13 found, for the predetermined 01 spectrum 5 , part 25 , a switch 1 , part 22 , the filter 2 , part 15 , a switch 2 , part 16 , a filter 3 , part 17 , a switch 3 , part 18 , a switch 4 , part 19 , a data bus 3 , part 24 , a battery 20 and a permanent memory for the executable program 6 , part 23 and a filter 1 , part 26 .

The microprocessor 2 is conditioned by the program so that it performs a 124 point Fourie transformation from the first data block of the memory 3 , functional level A and the power spectrum as explained in the description of the invention, calculated, which is then programmed via the switch 1 , part 22 the filter 1 , part 26 for testing the initial frequency of the pattern to be passed on.

When filtering, the microprocessor is caused to subject the block from which the 124 point Fourie transformation was carried out to a 512 Point Fourie transformation, to calculate the power spectrum as explained in the description of the invention, and this via the data bus 2 , part 21 in the memory 2 , part 11 for the power spectrum, subjecting the next block to a 124 point Fouri transform if there is no filtering and transforming and analyzing this to the power spectrum. The program also enables the power range to be converted into positive values with a dB scale division of the Y values, to be stored in memory 2 , part 11 and to use the positive power spectrum to set a compensation curve and to store this in memory 3 , part 12 .

Furthermore, this functional level B carries out the subtraction of positive power spectrum minus compensation function in order to form the differential power spectrum already explained in the description, in order to calculate the 01 spectrum, which has also already been described, and to store it in memory 4 , part 13 . In addition, this functional level B compares the 01 spectrum found with an 01 spectrum stored in memory 6 , part 23 , and uses the correlation coefficient calculated by the program to determine which 01 pattern comes closest and matches the irradiated pattern the correlation coefficient with a 10-pattern code and transfers this correlation-code combination to the switch 2 , part 16 to filter 2 , part 15 , filter 2 checking whether the signal pattern emitted by the transmitter matches that in memory 5 , part 25 corresponds to the stored pattern and, if not filtered, causes the microprocessor to analyze the next data block and therefore to start the recognition process again and to pass the code number to filter 3 , part 17 , which controls filter switch 1 , part 22 to the state when filtering "off" sets and when not filtering the control switch 1 to the "on" state, and again after a Z time delay gives a control signal to the microprocessor 2 , on which analyzes the most recent data block in the manner described. The states "off" and "on" correspond to the control signal which sets the device to be controlled in the desired state.

In addition, this function level B consists of the switch 4 to be operated, part 19 of the microprocessor 2 , part 14 causes the filter 1 , part 13 to be reconditioned and a new 01 pattern in the memory 5 , part 14 , for the comparison of store input patterns to be analyzed and assign a key figure to the new permanent pattern to define the status of the device to be controlled. The battery 1 , part 20 ensures that the memory 5 , part 14 and the memory 6 , part 23 , for the program of the microprocessor 2 , part 14 even in the operating state "off" of the control unit, the structures stored in it are not deleted .

Reference symbol list

1 recipient
2 analog / digital converters
3 memories for the digitized data
4 timer 1
5 clock 2
6 bandpass 0-2000 Mz
7 data bus
8 microprocessor 1
9 timer 2
10 clock 2
11 memory 2
12 memory 3
13 memory 4
14 microprocessor 2
15 filter 2
16 switch 2
17 filter 3
18 switch 3
19 switch 4
20 battery
21 Data bus 2
22 switch 1
23 memory 6
24 Data bus 3
25 memory 5
26 filter 1

Claims (10)

1. Method for controlling demodulators of electromagnetic signals, in particular for video and radio devices, on the basis of a fixed structure of the signals, characterized in that the signatures emitted by a transmitter are permanently detected and are supplied to an electrical device which contains a mathematical model which transfers these received electromagnetic signals into the frequency level and creates a power spectrum from them and forms a positive amount by shifting the y-axis in order to place a function A (f) through its local mean values, which then subtracts this from the power spectrum, which leads to a differential power spectrum, which is then transformed by the mathematical model in a next step to a spectrum consisting only of the values zero and one (01 spectrum) and for this a suitable 01 spectrum determined from a stored supply of 01 spectra and dependent g classified as a type of signal based on the match found. 2. Device for controlling demodulators electromagnetic table signals especially for video and radio devices due to a fixed structure of the signals characterized, that they be from functional levels formed by microcomputers stands, each part of the mathematical Mo contain dells and are controlled so that the Ver drive according to claim 1 is performed. 3. Device according to claim 2, characterized,  that a switch that is controlled by the result of a class sification or from a time with a clock to a first electronic function level is coupled. 4. Device according to claim 1 and 3, characterized, that the electronic functional level with a signal a signal pickup is applied from a Mikrocom computer consists of at least the functional elements Bandpass, converter, analog / digital converter, timer, Clock generator, microprocessor, data bus, memory, a switch is built in the output data bus and from one in one Memory stored program, which is the functional level enables data received from the transmitter to be saved in such a way that 6 times can be saved for 2 seconds. 5. Device according to claims 2 to 4, characterized, that a power spectrum from the collected signals of the transmitter emitting electromagnetic signals, preferably in the range 0-1600 Hz, with a resolution of 8 Hz too is calculated, and according to the program, the calculated power spectrum is forwarded to a filter. 6. Devices according to claims 2 to 5, characterized, that the electronic function level according to claim 5 with a functional part for signal reception classification tert, which consists of the electronic functional elements Fil for testing an adjustable minimum frequency, Filters for testing a largest frequency and filters for Creation of an amplitude value greater than a predetermined one Threshold value and a program stored in a memory, which causes the microprocessor from the performance spec  to determine the frequency values and the amplitude values and to open a switch so that these values can be reached by means of of a filter to the conditions in the specified frequency tervall lying and with an amplitude value above the Threshold can be checked and a non-filtering Control switches that the system according to the state Claim 5 offset at the beginning and when filtering the micro processor the performance spectrum with a resolution of 2 Hz and a range of 1-1600 Hz calculated and according to the program the calculated power spectrum via a switch to a forwards the following functional level. 7. Device according to claims 2 to 6, characterized, that the electronic functional level according to claim 4 a Another electronic function level follows, which is based on the elec tronic functional elements microprocessor, data bus, time encoder, clock generator each a storage space for the power spectrum, for the found compensation curve, for a positive logarithmic frequency pattern and an 01 spectrum exists, wherein the functional level by means of a in a memory laid program is capable that in a first electro African functional level calculated according to claim 5 chart in positive values with logarithmic scales division of the Y value and converted by the local Mit a function in order to calculate it from the subtract the range of services and to a 01 spectrum transform that the electronic level also pro stored in a memory controlled by granm. 8. Device according to claim 7, characterized, that the electronic functional level by a functional part for signal classification is extended from the to additional electronic functional elements memory memory cher for known 01 spectra and to complete one  Classification of an opened signal the microprocessor the functional level according to claim 6 by means of an additional controls stored in a program so that the 01 spectrum stored of a signal with, in a memory Memory spectrum stored 01 spectrum is compared and in the case of a preselectable match, the classification as is successfully declared and a switch is activated and if there is no match, the system in moved its state according to the beginning of claim 5 becomes. 9. Device according to claim 8, characterized, that the electronic functional level by a functional part to control a device that is made up of additional electronic functional elements two filters and switch exists and based on the classification result the functional level according to claim 7 of the filter Switches a control signal to a device outside of the tax some can give up. 10. Device according to claim 8, characterized, that the electronic functional level by a functional part for conditioning and permanent storage of the con dated 01 pattern consists of the functional elements ten battery and switch, the switch the Mi Croprocessor of the functional level according to claim 7 by means of a additionally stored in a memory in the Zu stood the filter properties of the filter after on to change saying 5 and the permanently saved 01- Redefine the spectrum, which is then carried out by the battery manent held in the memory according to claim 7 becomes. Furthermore, the battery serves that the Microprocessor controlling program in a separate memory  also received for the operating state "off" of the control unit remains.