CA1312130C - Identification friend from foe device - Google Patents
Identification friend from foe deviceInfo
- Publication number
- CA1312130C CA1312130C CA000541900A CA541900A CA1312130C CA 1312130 C CA1312130 C CA 1312130C CA 000541900 A CA000541900 A CA 000541900A CA 541900 A CA541900 A CA 541900A CA 1312130 C CA1312130 C CA 1312130C
- Authority
- CA
- Canada
- Prior art keywords
- radio
- signals
- light
- iff
- transceiver
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/74—Systems using reradiation of electromagnetic waves other than radio waves, e.g. IFF, i.e. identification of friend or foe
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/74—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems
- G01S13/76—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems wherein pulse-type signals are transmitted
- G01S13/78—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems wherein pulse-type signals are transmitted discriminating between different kinds of targets, e.g. IFF-radar, i.e. identification of friend or foe
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/86—Combinations of radar systems with non-radar systems, e.g. sonar, direction finder
- G01S13/865—Combination of radar systems with lidar systems
Landscapes
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Physics & Mathematics (AREA)
- Computer Networks & Wireless Communication (AREA)
- General Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Radar Systems Or Details Thereof (AREA)
- Optical Radar Systems And Details Thereof (AREA)
- Optical Communication System (AREA)
- Traffic Control Systems (AREA)
- Toys (AREA)
Abstract
Abstract Identification Friend from Foe Device An identification friend from foe (IFF) device is de-scribed containing a radio transceiver (F) which, in addition to being designed for communication purposes, is equipped for transmitting, receiving, and evaluating IFF signals. The IFF device further includes a laser transmitter (LS) and an optical receiver (LE) which are coupled to the radio transceiver (F) via a con-troller (G). For identification, unmodulated direction-selective light signals and modulated nondirectional radio signals are used.
D.Roth 3
D.Roth 3
Description
13~2~
Identification Frie~d from Foe Device The present invention relates to an identification friend from foe (IFF) device. Such devices are kno~n.
DE-AS 20 05 ~57, for example, discloses an IFF system which operates on the radar (particularly secondary radar) prin-ciple.
German Patent 29 39 959 discloses an IFF system which operates with coded light signals.
Such systems require costly and complicated equipment.
It is therefore the object of the present invention to provide a low-cost IFF system.
According to a broad aspect of the invention there is provided identification of friend from foe (IFF) apparatus comprising a light transmitter, a light receiver, a radio trans-ceiver for transmitting and receiving radio signals including communication signals and IFF signals, said transceiver including means for evaluating validity of received IFF signals, and a controller which, in response to detection by said light receiver of reflected light from a target illuminated by said light trans-mitter, causes said radio transceiver to transmit an interrogationsignal and then switches the transceiver to receive radio signals for a predetermined period of time.
According to another broad aspect of the invention there is provided identification of friend from foe (IFF) apparatus comprising a light transmitter, a light receiverj a radio trans-ceiver for transmitting and receiving radio signals including communication signals and IFF signals, said transceiver including ~ -- 1 --~ ~?
62046-1~6 means for evaluating validity of received IFF signals, and a con-troller which, in response to detection of light by said light receiver, switches the transceiver to receive radio signals for a predetermined period of time and, upon reception of an interroga-tion signal, switches the transceiver to transmit a reply signal.
The invention has the advantage that, thanks to the multiple utilization of electronic and optical equipment present in a weapon system, not only a considerable cost reduction but also space savings and logistic advantages are achieved.
An embodiment of the invention will now be explained with r _ "'.
~3~ 2~ ~3 reference to the accompanying drawing, which is a schematic circuit diagram of the novel IFF device.
The IFF device contains a radio unit F with a transmitting section S, a receiving section E, an encoder C, and a decoder D. It further includes a light transmitter LS, wh;ch may be a laser range finder forming part of a weapon system, a light receiver LE, e.g., a laser warning reseiver, a controller G, and d;splays A1 - A5, wh;ch may be structurally united with the controller G. The latter contains a control circuit, of which only the components necessary to understand the principle of operation, namely AND gates U and an inverter stage for driving the displays A1 and A2, and three delaY elements T, are shown in Fig. 1. Connected to the controLler G
is a trigger I.
The radio transmission of interrogation and reply sig-nals must meet certain requirements with respect to communication security, deception resistance, and jam res;stance. A suitable transmission technique is the frequency-hopping technique, for example.
The identification decision is derived by transmitting electronic interrogation siqnals which are aroduced in the encoder C during the range measurement process. These interrogation signals, which must be agreed anew every day, for example, are triggered via the trigger I. Simultaneously with the triggering of these in-terrogation signals, the display "identification in progress" appears on the disolay unit A5.
D.Roth 5 3 ~
As soon as the transmission of the interrogation signal has been completed, the control circuit of the con-troller G of the interro~ating station switches the radio unit from transmission to reception and now waits for the agreed reply signal to follow the interrogat;on signal transmitted by radio in the frequency-hopping mode shortly after the laser pulse.
When the light receiver LE of the responding station has signalled the reception of a laser pulse from any particular direction (optically omnidirectional antenna ), the display laser reception appears on the display unit A4. At the same time, when a laser pulse is received by the light receiver, the receiver E of the radio unit F of the responding station is set to a mode in which the interrogation signals can be received and evaluated.
If the result of the evaluation performed in the decoder D with the code valid during the respective period is positive, i.e~, if agreed interrogation signals have been detected, the responding station s radio unit will be switched from reception to transmission in the shortest possible time. The elicited reply signals are generated electronically by the encoder C of the radio unit,and transmitted to the interrogating station in the frequency-hopping mode, too. Upon com~letion of the transmission of reply signals, the laser reception warning signal is cancelled.
The reply signals expected in response to the interro-gation signals now arrive at the interrogating station in the receiver of the radio unit. As the receiver is already , D.Roth 3 .
. .
, , . , j . ~ - ~ i prepared for reception of these signals, the latter can be evalua-ted with a minimum delay. If the result of the evaluation of t'ne information conveyed by the reply signals is positive, it must be assumed, in view of the fact that the reply signals transmitted by an ECCM (electronic counter-countermeasures) technique are secure against deception, that the interrogated station has sent out the reply and can thus be classified as a friend. In this case, the display "friend" appears on the display unit A3 of the interrogat-ing station. ~hen the "friend" display is cancelled, the "identi-fication in progress" display disappears. The device is thenready to carry out a new identification.
As described above, after transmission of the interroga-tion signals, the radio unit of the interrogator switches from the transmit condition to the receive condition. To permit reception of a possible reply from the interrogated object, the receiver of the interrogator attempts to detect and evaluate agreed reply signals. If this attempt is unsuccessful after a predetermined period of time, the receiver initia-tes the display "foe" on the display unit A2. Since the target range of the object identified as a foe is simultaneously provided by the laser range finder, such a target can be combated immediately.
If a friendly weapon system equipped with an IFF device according to the invention is illuminated by the laser source of a hostile weapon system, the sequence of operations is as follows.
r . ~
~ 2~ ~
The laser warning receiver LE detects the illumination with laser light and causes the display "laser reception"
to appear on the d;splay unit A4. It is in a position to indicate the direction from which the laser light was received. If laser light is received only in the laser warning receiver LE, it is not generally possible to reliably and unambiguously identify the transmitter.
Therefore, upon receiving laser light, the laser warning receiver will immediately activate the receiver of the radlo unit, so that any interrogation sianal can be received and evaluated. If a friendly object is illuminat-ed by the laser range finder of a hostile object, no interrogation signal will be present.
This result is available after the lapse of a prede-termined time interval folLowing the detection of the reception of laser light by the laser warning receiver.
Based on the absence of an interrogation signaL it can only be stated that the illumination with laser light came from a still unidentified object (A1). With the aid of the directional information provided by the laser warning receiver, the target can be detected without a time-consuming search process. To make sure that the ob-ject is really a hostile object, an identification process as described above can now be initiated.
The principle of the proposed IFF system must permit un-ambiguous identification decisions even when several ident;fying objects and several objects to be identified are operating within a limited geographical area. The identifying objects are friendly objects. The objects to be identified can be either friendly objects or hostile objects.
D.Roth 3 , . .. ~.
To unambiguously distinguish friend from foe, electronic interrogation signals are sent out by the interrogator of the novel dev;ce shortly after the laser pulse. These electronic interrogation signals are transmitted by radio in such a way as to be resistant to jamming and secure against deception. However, since they are trans-mitted by the interrogator via omnidirectional antennas, they can be received by any receiving station located within the coverage. Through the directional selectivity of the laser beam in the direction of interrogation, however, spatial selectivity is achieved which covers only one object to be identified. In the interrogator, therefore, the laser range finder and the radio unit are coupled by the controller G to compensate for the lack of spatial select;vity of the radio antenna used.
In the responding station, coupling is provided oetween the laser warning receiver and the radio unit. This makes it possible upon reception of laser light to put the radio unit, irrespective of its current operating con-dition, in a condition in which it can rece;ve and evaluate any interrogation signal in the intended manner. Thus, because of the directional selectivity of the laser beam, only the object illuminated by it will respond provided it is a friend.
Because of the use of the existing antenna, the station illuminated by the laser beam radiates the reply signals in all horizontal directions, too. Nevertheless, thanks to the transmission technique used, the reply can only be received and evaluated by the interrogating station which initiated the identification process. All other D.Roth 3 1 .3 ~
objects within the coverage of the radio unit, which re-ceive the reply as well, are not prepared for the re-ception of the reply signals, i.e., are not in the mode intended therefor. They are "deaf" to these reply signals.
Thus, even inthe presence of several identifying objects and several objects to be identified, selective in-terrogation of an object is still possible, and the reply of the interrogated object can only be evaluated by the interrogating station which initiated the identification process.
The situation just described assumes that the identifi-cation processes carr;ed out by the individual in-terrogating stations are separated in time. As the number of identifying interrogators and respond1ng objects increases, however~ the identification processes of ;ndividual interrogators may overlap in time, i.e., during the identification process, an identifying object may be interrogated by another identifying object, or an object to be identified may be illuminated with laser light from a hostile weapon system. Such situations must not be critical for a friendly weapon system. The above-described basic concept does not yet include per-mitting an identifying object or an object to be iden-tified (friendly weapon systems) to be additionally interrogated by another object during an initiated and partially executed identification process. As a result, the reception of a laser pulse is registered and indicated, but any interrogation signal transmitted simultaneously with the laser pulse cannot be received - by the receiver of the radio unit.
D.Roth 3 : ~ " ~ ': : ' :
.
~3~ ~3~
To solve this problem, an additional radio unit i5 re-quired in each IFF device. It permits the interrogation signals arrivin~ from another object during an iden-tification process to be rece;ved and evaluated without the current identification sequence having to be in-terrupted either in the identifying object or in the object to be identified. The advantages of this method are that the reliability of the identification decision is not affected, and that an optimum reaction time can be achieved. The price to be paid for this is an additional radio unit.
With the expanded basic concept, the execution of an identification process cannot become a risk for the identifying station.
. . :~ . ., . : ;
Identification Frie~d from Foe Device The present invention relates to an identification friend from foe (IFF) device. Such devices are kno~n.
DE-AS 20 05 ~57, for example, discloses an IFF system which operates on the radar (particularly secondary radar) prin-ciple.
German Patent 29 39 959 discloses an IFF system which operates with coded light signals.
Such systems require costly and complicated equipment.
It is therefore the object of the present invention to provide a low-cost IFF system.
According to a broad aspect of the invention there is provided identification of friend from foe (IFF) apparatus comprising a light transmitter, a light receiver, a radio trans-ceiver for transmitting and receiving radio signals including communication signals and IFF signals, said transceiver including means for evaluating validity of received IFF signals, and a controller which, in response to detection by said light receiver of reflected light from a target illuminated by said light trans-mitter, causes said radio transceiver to transmit an interrogationsignal and then switches the transceiver to receive radio signals for a predetermined period of time.
According to another broad aspect of the invention there is provided identification of friend from foe (IFF) apparatus comprising a light transmitter, a light receiverj a radio trans-ceiver for transmitting and receiving radio signals including communication signals and IFF signals, said transceiver including ~ -- 1 --~ ~?
62046-1~6 means for evaluating validity of received IFF signals, and a con-troller which, in response to detection of light by said light receiver, switches the transceiver to receive radio signals for a predetermined period of time and, upon reception of an interroga-tion signal, switches the transceiver to transmit a reply signal.
The invention has the advantage that, thanks to the multiple utilization of electronic and optical equipment present in a weapon system, not only a considerable cost reduction but also space savings and logistic advantages are achieved.
An embodiment of the invention will now be explained with r _ "'.
~3~ 2~ ~3 reference to the accompanying drawing, which is a schematic circuit diagram of the novel IFF device.
The IFF device contains a radio unit F with a transmitting section S, a receiving section E, an encoder C, and a decoder D. It further includes a light transmitter LS, wh;ch may be a laser range finder forming part of a weapon system, a light receiver LE, e.g., a laser warning reseiver, a controller G, and d;splays A1 - A5, wh;ch may be structurally united with the controller G. The latter contains a control circuit, of which only the components necessary to understand the principle of operation, namely AND gates U and an inverter stage for driving the displays A1 and A2, and three delaY elements T, are shown in Fig. 1. Connected to the controLler G
is a trigger I.
The radio transmission of interrogation and reply sig-nals must meet certain requirements with respect to communication security, deception resistance, and jam res;stance. A suitable transmission technique is the frequency-hopping technique, for example.
The identification decision is derived by transmitting electronic interrogation siqnals which are aroduced in the encoder C during the range measurement process. These interrogation signals, which must be agreed anew every day, for example, are triggered via the trigger I. Simultaneously with the triggering of these in-terrogation signals, the display "identification in progress" appears on the disolay unit A5.
D.Roth 5 3 ~
As soon as the transmission of the interrogation signal has been completed, the control circuit of the con-troller G of the interro~ating station switches the radio unit from transmission to reception and now waits for the agreed reply signal to follow the interrogat;on signal transmitted by radio in the frequency-hopping mode shortly after the laser pulse.
When the light receiver LE of the responding station has signalled the reception of a laser pulse from any particular direction (optically omnidirectional antenna ), the display laser reception appears on the display unit A4. At the same time, when a laser pulse is received by the light receiver, the receiver E of the radio unit F of the responding station is set to a mode in which the interrogation signals can be received and evaluated.
If the result of the evaluation performed in the decoder D with the code valid during the respective period is positive, i.e~, if agreed interrogation signals have been detected, the responding station s radio unit will be switched from reception to transmission in the shortest possible time. The elicited reply signals are generated electronically by the encoder C of the radio unit,and transmitted to the interrogating station in the frequency-hopping mode, too. Upon com~letion of the transmission of reply signals, the laser reception warning signal is cancelled.
The reply signals expected in response to the interro-gation signals now arrive at the interrogating station in the receiver of the radio unit. As the receiver is already , D.Roth 3 .
. .
, , . , j . ~ - ~ i prepared for reception of these signals, the latter can be evalua-ted with a minimum delay. If the result of the evaluation of t'ne information conveyed by the reply signals is positive, it must be assumed, in view of the fact that the reply signals transmitted by an ECCM (electronic counter-countermeasures) technique are secure against deception, that the interrogated station has sent out the reply and can thus be classified as a friend. In this case, the display "friend" appears on the display unit A3 of the interrogat-ing station. ~hen the "friend" display is cancelled, the "identi-fication in progress" display disappears. The device is thenready to carry out a new identification.
As described above, after transmission of the interroga-tion signals, the radio unit of the interrogator switches from the transmit condition to the receive condition. To permit reception of a possible reply from the interrogated object, the receiver of the interrogator attempts to detect and evaluate agreed reply signals. If this attempt is unsuccessful after a predetermined period of time, the receiver initia-tes the display "foe" on the display unit A2. Since the target range of the object identified as a foe is simultaneously provided by the laser range finder, such a target can be combated immediately.
If a friendly weapon system equipped with an IFF device according to the invention is illuminated by the laser source of a hostile weapon system, the sequence of operations is as follows.
r . ~
~ 2~ ~
The laser warning receiver LE detects the illumination with laser light and causes the display "laser reception"
to appear on the d;splay unit A4. It is in a position to indicate the direction from which the laser light was received. If laser light is received only in the laser warning receiver LE, it is not generally possible to reliably and unambiguously identify the transmitter.
Therefore, upon receiving laser light, the laser warning receiver will immediately activate the receiver of the radlo unit, so that any interrogation sianal can be received and evaluated. If a friendly object is illuminat-ed by the laser range finder of a hostile object, no interrogation signal will be present.
This result is available after the lapse of a prede-termined time interval folLowing the detection of the reception of laser light by the laser warning receiver.
Based on the absence of an interrogation signaL it can only be stated that the illumination with laser light came from a still unidentified object (A1). With the aid of the directional information provided by the laser warning receiver, the target can be detected without a time-consuming search process. To make sure that the ob-ject is really a hostile object, an identification process as described above can now be initiated.
The principle of the proposed IFF system must permit un-ambiguous identification decisions even when several ident;fying objects and several objects to be identified are operating within a limited geographical area. The identifying objects are friendly objects. The objects to be identified can be either friendly objects or hostile objects.
D.Roth 3 , . .. ~.
To unambiguously distinguish friend from foe, electronic interrogation signals are sent out by the interrogator of the novel dev;ce shortly after the laser pulse. These electronic interrogation signals are transmitted by radio in such a way as to be resistant to jamming and secure against deception. However, since they are trans-mitted by the interrogator via omnidirectional antennas, they can be received by any receiving station located within the coverage. Through the directional selectivity of the laser beam in the direction of interrogation, however, spatial selectivity is achieved which covers only one object to be identified. In the interrogator, therefore, the laser range finder and the radio unit are coupled by the controller G to compensate for the lack of spatial select;vity of the radio antenna used.
In the responding station, coupling is provided oetween the laser warning receiver and the radio unit. This makes it possible upon reception of laser light to put the radio unit, irrespective of its current operating con-dition, in a condition in which it can rece;ve and evaluate any interrogation signal in the intended manner. Thus, because of the directional selectivity of the laser beam, only the object illuminated by it will respond provided it is a friend.
Because of the use of the existing antenna, the station illuminated by the laser beam radiates the reply signals in all horizontal directions, too. Nevertheless, thanks to the transmission technique used, the reply can only be received and evaluated by the interrogating station which initiated the identification process. All other D.Roth 3 1 .3 ~
objects within the coverage of the radio unit, which re-ceive the reply as well, are not prepared for the re-ception of the reply signals, i.e., are not in the mode intended therefor. They are "deaf" to these reply signals.
Thus, even inthe presence of several identifying objects and several objects to be identified, selective in-terrogation of an object is still possible, and the reply of the interrogated object can only be evaluated by the interrogating station which initiated the identification process.
The situation just described assumes that the identifi-cation processes carr;ed out by the individual in-terrogating stations are separated in time. As the number of identifying interrogators and respond1ng objects increases, however~ the identification processes of ;ndividual interrogators may overlap in time, i.e., during the identification process, an identifying object may be interrogated by another identifying object, or an object to be identified may be illuminated with laser light from a hostile weapon system. Such situations must not be critical for a friendly weapon system. The above-described basic concept does not yet include per-mitting an identifying object or an object to be iden-tified (friendly weapon systems) to be additionally interrogated by another object during an initiated and partially executed identification process. As a result, the reception of a laser pulse is registered and indicated, but any interrogation signal transmitted simultaneously with the laser pulse cannot be received - by the receiver of the radio unit.
D.Roth 3 : ~ " ~ ': : ' :
.
~3~ ~3~
To solve this problem, an additional radio unit i5 re-quired in each IFF device. It permits the interrogation signals arrivin~ from another object during an iden-tification process to be rece;ved and evaluated without the current identification sequence having to be in-terrupted either in the identifying object or in the object to be identified. The advantages of this method are that the reliability of the identification decision is not affected, and that an optimum reaction time can be achieved. The price to be paid for this is an additional radio unit.
With the expanded basic concept, the execution of an identification process cannot become a risk for the identifying station.
. . :~ . ., . : ;
Claims (7)
1. Identification of friend from foe (IFF) apparatus comprising a light transmitter, a light receiver, a radio trans-ceiver for transmitting and receiving radio signals including communication signals and IFF signals, said transceiver including means for evaluating validity of received IFF signals, and a controller which, in response to detection by said light receiver of reflected light from a target illuminated by said light trans-mitter, causes said radio transceiver to transmit an interrogation signal and then switches the transceiver to receive radio signals for a predetermined period of time.
2. Identification of friend from foe (IFF) apparatus comprising a light transmitter, a light receiver, a radio trans-ceiver for transmitting and receiving radio signals including communication signals and IFF signals, said transceiver including means for evaluating validity of received IFF signals, and a controller which, in response to detection of light by said light receiver, switches the transceiver to receive radio signals for a predetermined period of time and, upon reception of an interroga-tion signal, switches the transceiver to transmit a reply signal.
3. An apparatus as claimed in claim 1 or 2, characterized in that the light receiver indicates by means of a display that a light signal was received, and includes a display for the direc-tion from which the light was received.
4. An apparatus as claimed in claim 2, characterized in that only after receiving a particular radio signal within a first period of time does it send out a radio reply signal within a subsequent second period of time.
5. An apparatus as claimed in claim 3, characterized in that, after sending out the radio reply signal, it switches the radio transceiver to reception for a third period of time, and that it makes the decision "friend" only if a particular radio signal is received within this third period of time, and otherwise makes the decision "foe".
6. An apparatus as claimed in claim 1, 2 or 5, character-ized in that the radio transceiver is a VHF transceiver.
7. An apparatus as claimed in claim 1, 2 or 5, character-ized in that at least the transmission of the radio interrogation and reply signals is effected using an ECCM (electronic counter-countermeasures) technique.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP3624143.1 | 1986-07-17 | ||
| DE19863624143 DE3624143A1 (en) | 1986-07-17 | 1986-07-17 | DEVICE FOR FRIEND-ENEMY IDENTIFICATION |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1312130C true CA1312130C (en) | 1992-12-29 |
Family
ID=6305375
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000541900A Expired - Lifetime CA1312130C (en) | 1986-07-17 | 1987-07-13 | Identification friend from foe device |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP0254197B1 (en) |
| CA (1) | CA1312130C (en) |
| DE (2) | DE3624143A1 (en) |
| DK (1) | DK370587A (en) |
| ES (1) | ES2039381T3 (en) |
| GR (1) | GR3007111T3 (en) |
| NO (1) | NO170043C (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19523399C2 (en) * | 1995-06-28 | 2001-04-26 | Mauser Werke Oberndorf Waffensysteme Gmbh | Handgun |
| US5966226A (en) * | 1996-10-11 | 1999-10-12 | Oerlikon-Contraves Ag | Combat communication system |
| US6235249B1 (en) | 1997-04-01 | 2001-05-22 | Engelhard Corporation | Rotary oxidizer systems for control of restaurant emissions |
| CH694668A5 (en) | 2000-05-12 | 2005-05-31 | Ruag Electronics | Identification and simulation system and method for simulating a shot. |
| KR102134178B1 (en) | 2012-08-09 | 2020-07-16 | 이스라엘 에어로스페이스 인더스트리즈 리미티드 | Friend or foe identification system and method |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE520931A (en) * | 1952-06-25 | |||
| DE2215463B2 (en) * | 1972-03-29 | 1975-07-10 | Precitronic Gesellschaft Fuer Feinmechanik Und Electronic Mbh, 2000 Hamburg | Friend-or-foe identifier on weapon - uses laser interrogator and receiver for response from responder at target, in parallel line of sight |
| DE2251295A1 (en) * | 1972-10-19 | 1974-05-02 | Eltro Gmbh | PROCEDURES FOR FRIEND / FEE IDENTIFICATION |
| NZ206185A (en) * | 1982-11-09 | 1987-01-23 | Australian Meat & Live Stock | Radio transmitter transmits coded signal when triggered by light beam |
| FR2574948B1 (en) * | 1984-12-14 | 1987-01-16 | Thomson Csf | FRIEND-FRIENDLY QUERY METHOD AND SYSTEM USING THE SAME |
-
1986
- 1986-07-17 DE DE19863624143 patent/DE3624143A1/en not_active Withdrawn
-
1987
- 1987-06-29 NO NO872711A patent/NO170043C/en unknown
- 1987-07-13 CA CA000541900A patent/CA1312130C/en not_active Expired - Lifetime
- 1987-07-15 ES ES198787110208T patent/ES2039381T3/en not_active Expired - Lifetime
- 1987-07-15 DE DE8787110208T patent/DE3783964D1/en not_active Expired - Fee Related
- 1987-07-15 EP EP87110208A patent/EP0254197B1/en not_active Expired - Lifetime
- 1987-07-16 DK DK370587A patent/DK370587A/en not_active Application Discontinuation
-
1993
- 1993-02-19 GR GR930400346T patent/GR3007111T3/el unknown
Also Published As
| Publication number | Publication date |
|---|---|
| DK370587D0 (en) | 1987-07-16 |
| NO872711L (en) | 1988-01-18 |
| EP0254197A1 (en) | 1988-01-27 |
| NO872711D0 (en) | 1987-06-29 |
| ES2039381T3 (en) | 1993-10-01 |
| GR3007111T3 (en) | 1993-07-30 |
| NO170043C (en) | 1992-09-02 |
| NO170043B (en) | 1992-05-25 |
| DE3624143A1 (en) | 1988-01-21 |
| DK370587A (en) | 1988-01-18 |
| DE3783964D1 (en) | 1993-03-18 |
| EP0254197B1 (en) | 1993-02-03 |
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