DE2113087A1 - Arrangement for the operation of telemetry devices - Google Patents

Description

Siemens Aktiengesellschaft Erlangen, March 16, 1997I

Henkestrasse 127

VPA 71/5029 kue-ki

Arrangement for the operation of telemetry devices

The invention relates to an arrangement for the operation of telemetry devices, in which by staggered intervals a single selective receiver to the different frequencies of a plurality of telemetry transmitters the individual received transmitter signals occur as time-staggered signal pulses at the receiver output and pass through there Sampling can be separated again according to the vote.

With such arrangements one is in the interest of an interference-free transmission and an optimal utilization of the available Frequency channels strive to keep the bandwidth of the receiver as low as possible and with correspondingly steep edges Filter arrangements the selection to frequency adjacent tone To drive channels as high as possible. Such narrow band and steep-edged filters respond to an approximately rectangular one Einojig's impulse, as it is due to the time

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staggered coordination of the selective recipient in each case ~ there, with a pronounced swing-in and swing-out process. this means that a signal (decay signal) is still emitted at the output of the filter when the signal pulse at the input the filter has already subsided. With simultaneous start of voting and sampling at the output of the receiver this signal would fall into the subsequent channel and thus superimposed on it as interference (so-called crosstalk) be. · ·

^ The object of the invention is to provide an arrangement of the aforementioned Specify the type in which such a disruption practically does not occur.

The object is achieved according to the invention in that each scanning by approximately the decay time of a previous one Signal pulse corresponding time delayed to .the beginning of the respective associated vote takes place.

The solution according to the invention ensures that a signal pulse is only fed to the corresponding output channel when the oscillation of the preceding signal pulse has already subsided. An interference of this w Ausschwingung to the next channel can therefore no longer occur.

In arrangements according to the invention in which the duration of a vote or a corresponding sampling by the Duration of a tuning or sampling pulse is specified, the respective sampling pulse is compared to the associated tuning pulse preferably by half the pulse duration of the tuning pulse delayed. Practice has shown that the decay time of a signal pulse is practically always shorter

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than half the duration of a voting pulse. With such arrangements the duration of the sampling pulse should also correspond to half the duration of the associated tuning pulse, i.e. the Voting pulse and its associated sampling pulse should each end at the same time. As a result, the individual tuning pulses can follow one another practically without delay and thus the available frequency channels are optimal be exploited.

In arrangements in which the staggered coordination of the receiver with the individual transmission frequencies by alternating Switching on mixer oscillators of the appropriate frequency to a receiver mixer stage is a simple one Synchronization of the individual impulses within the scope of the task achieved in that the connection pulses (tuning pulses) and the scanning pulses from a common Clock generator are generated.

An exemplary embodiment is shown below with reference to the drawing of the invention described and its mode of operation explained.

In FIG. 1, which shows the basic circuit diagram of the invention, 1, 2 and 3 denote three telemetry transmitters which have their transmitting antennas 4, 5 and 6 on different frequencies measurement data, such as body action voltages or other physiological Values of individual test subjects, or the like. send out.

The individual signals from transmitters 1 to 3 are transmitted by the receiving antenna 7 of a receiver 8 added. The signals are recorded by coordinating the Receiver 8 on the individual transmission frequencies.

The receiver 8 consists essentially of one of the antenna downstream high-frequency preamplifier 9, one M ± sch-

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stage 10, an intermediate frequency amplifier 11, a demodulation stage 12 and mixer oscillators 13, 14, 15 with frequencies corresponding to the transmission frequencies, which can be individually connected to the mixer 10 via switches 16, 17 and 18. The receiver 8 also contains a clock generator 19 which _{supplies sequences U 1} Ct), U ₅ Ct) and U ₅ (t) according to FIG. 2 of switch-on pulses for the switches 16, 17 and 18 at three outputs 20, 21 and 22.

The pulses of the pulse trains U ₁ Ct), U, (t) and U ^ (t) cause the switches 16 to 18 to be switched on alternately one after the other, i.e. the mixer oscillators 13 to 15 are switched on alternately one after the other to the mixer stage 10 . Because of this staggered connection of the oscillators 13 ″ to 15, the received transmitter signals occur at the output of the receiver 8 as signal pulses staggered in time.

The separation of the signal pulses at the output of the receiver 8, ie the correct feeding of the respective pulses associated with a transmitter signal to the corresponding output channels 23> 24 and 25 for the signals of the transmitters 1, 2 and 3, is done using switches 26, 27 and 28, which alternately turn on the individual channels 23 up to the receiver output in accordance with the switches 16, 17 and 18 for the * mixer oscillators 13, 14 and 15. The respective switching cycle of the switches 26 to 28 is determined by pulse sequences Up (t), U, (t) and UgCt) generated at three further outputs 30 and 31 of the clock generator 19 according to FIG. _{The pulses U 2} , U. and Ug occurring at the respective outputs 29, 30 and 31 have half the pulse duration of the pulses U-, U ~ and Uf- occurring at the corresponding outputs 20, 21 and 22, with the pulses U ₁ and U ₂ , U, and U. as well as U _R and Ug each end at the same point in time, ie are delayed by half their pulse duration _{compared to the beginning of the corresponding pulses U 1} , U ~, U _5.

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The circuit elements 32, 33, 34 in the output channels 23, 24, 25 represent low-pass filters for the individual transmitter signals.

In Pig. 3, a signal pulse U _s (t) is recorded, as it is generated due to the connection of a mixer oscillator (eg 13) to the mixer stage 10 at its output. The associated pulse at the output of the receiver 8 is denoted by U. (t). It can be seen that the pulse U ^ (t) has considerable swing-in and swing-out processes, which are generated in particular in the intermediate amplifier 11 due to the extremely selective filter.

Each oscillation of such a pulse U. (t) is superimposed the next following impulse. If now each switching pulse for the switches 26 to 28 would be simultaneous with the corresponding one Switching pulse for the switches 16 to 18 are generated, the oscillation of a pulse U. (t) in the The channel of the next impulse can also be transmitted and thus become noticeable as interference (crosstalk).

The inventive control of switches 16 to 18 and 26 to 28 on the basis of pulse sequences according to Pig. 2 prevents one such disturbance because each switching pulse for a switch 26 to 28 compared to the corresponding switching pulse for the switch 16 to 18 is delayed in the manner described above and thus superimposed oscillations of the previous one Impulse cannot take effect.

The invention can be used not only for arrangements of the described Use kind. It can also be used in time-division multiplex systems in which sampling is staggered in time of the individual transmitter signals these via a common transmission path to a single selective receiver

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transmitted and separated there again by appropriate scanning will. Both a transmitter-side and a receiver-side clock generator would then have to be provided, with the corresponding synchronization would take place via synchronization pulses.

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Claims (3)

Claims • π J arrangement for the operation of telemetry devices, in which the individual received transmitter signals occur as time-staggered signal pulses at the receiver output and are separated again there by sampling according to the coordination, by staggered adjustment of a single selective receiver to the different frequencies of a plurality of telemetry transmitters characterized in that each sampling is delayed by a period corresponding approximately to the decay period g of a preceding signal pulse (U.) to the beginning of the respective associated tuning. 2. Arrangement according to claim 1, in which the duration of a vote or a corresponding sampling by the duration a tuning or sampling pulse is set, characterized in that the respective Sampling pulse (Up, U., U ^) compared to your associated tuning pulse (U-, U ~, Up-) preferably by half the pulse duration of the Tuning pulse is delayed. 3. Arrangement according to claim 2, characterized in that the duration of the sampling pulse (Up, U., Ug) is half the duration of the associated tuning pulse (U. ,, U ^, Uf-) corresponds. 4 · Arrangement according to claim 2 to 3, in which the temporal Staggered tuning of the receiver to the individual transmission frequencies by alternately switching on mixed oscillato ren corresponding frequency to a receiver mixer stage, characterized in that the connection pulses (tuning pulses) and the scanning pulses can be generated by a common clock generator (19). 209839/0977 Lee r side