CA2175085A1 - Dual-mode wireless unit with two spread-spectrum frequency bands - Google Patents
Dual-mode wireless unit with two spread-spectrum frequency bandsInfo
- Publication number
- CA2175085A1 CA2175085A1 CA002175085A CA2175085A CA2175085A1 CA 2175085 A1 CA2175085 A1 CA 2175085A1 CA 002175085 A CA002175085 A CA 002175085A CA 2175085 A CA2175085 A CA 2175085A CA 2175085 A1 CA2175085 A1 CA 2175085A1
- Authority
- CA
- Canada
- Prior art keywords
- frequency
- output
- synthesizer
- range
- signal
- 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.)
- Abandoned
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J13/00—Code division multiplex systems
- H04J13/10—Code generation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J13/00—Code division multiplex systems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/005—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/005—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges
- H04B1/0053—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges with common antenna for more than one band
- H04B1/0057—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges with common antenna for more than one band using diplexing or multiplexing filters for selecting the desired band
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
- H04B1/40—Circuits
- H04B1/403—Circuits using the same oscillator for generating both the transmitter frequency and the receiver local oscillator frequency
- H04B1/406—Circuits using the same oscillator for generating both the transmitter frequency and the receiver local oscillator frequency with more than one transmission mode, e.g. analog and digital modes
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/24—Radio transmission systems, i.e. using radiation field for communication between two or more posts
- H04B7/26—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
- H04B7/2628—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA]
- H04B7/2634—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA] for channel frequency control
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/10—Frequency-modulated carrier systems, i.e. using frequency-shift keying
- H04L27/12—Modulator circuits; Transmitter circuits
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
- H04W88/02—Terminal devices
- H04W88/06—Terminal devices adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Quality & Reliability (AREA)
- Transmitters (AREA)
- Transceivers (AREA)
- Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
Abstract
The invention provides a dual-band spread-spectrum modulator (101, 103, 105) which uses a single, relatively narrow, synthesizer to serve two operating frequency bands (102, 104). In the lower frequency band, the synthesizer may operate in a high-side injection mode, while in the higher frequency range the synthesizer may operate in a low-side injection mode. In a preferred embodiment, the lower frequency range may comprise about 1850 to 1990 megahertz, while the higher frequency range may comprise about 2400 to 2483.5 megahertz.
Description
Wo 95112925 217 5 ~ ~ ~ PCTIUS94/1246.1 DESCRIPTIQN ~ :
Dual-Mode Wireless Unit With Two S~read-SPectrum Freauençy Bands Backqround of the Invention 1. Pield of the Inventiçn This invention relates to a dual moae wireless unit which uses two spread-spectrum communication bands.
5 2. Descri~tion of Related Art In spread-spectrum modulation in a wireless telephone system, operation in more than one frequency band can be difficult, due to the wide separation between frequency bands. For example, operation in the 900 megahertz and lO laO0 megahertz bands could require a synthesizer capable of covering approximately l, 000 megahertz in frequency spectrum. However, in hand-held equipment such as tele-phones, it is undesirable to use more than one synthesiz-er, or even more than one oscillator, due to increased 15 cost, weight, and related considerations.
Accordingly, it would be advantageous to provide a spread-spectrum system in which a single, relatively narrow, synthesi2er would serve more than one operating f requency band .
20 Summarv of the Invention The invention provides a dual-band spread-spectrum modulator which uses a single, relatively narrow, synthe-sizer to serYe two operating frequency bands. In the lower frequency band, the synthesizer may operate in a 25 high-side injection mode, while in the higher frequency range, the synthesizer may operate in a low-side injection mode. In a preferred embodiment, the lower frequency range may comprise about 1850 to l990 megahertz, while the higher frequency range may comprise about 2400 to 24a3 . 5 3 0 megahertz .
Wo 95/l2925 ~ O C~ PCTIUS94/12464 Brief Descril~tion of the Drawinqs Figure 1 shows a dual-mode spread-spectrum modulator with two frequency bands. s Figure 2 shows a pLU_~' hle frequency generator.
Descri~tion of the Preferred Embodiment Figure 1 shows a dual-mode spread-spectrum modulator with two frequency bands.
A first frequency source 101 may generate a first frequency fl 102, while a second frequency source 103 may generate a second frequency f2 104. The first frequency fl 102 and the second frequency f2 104 may be coupled to a multiplier 105, which may generate a bimodal signal 106 with a frequency distribution over two fres~uency ranges f~
107 and fH 108. In a preferred embodiment, the lower of the two frequencies fL 107 (f~ = fl - f2) may range from about 1850 to l990 megahertz, while the higher of the two frequencies fH 108 ~fH = fl + f2) may range from about 2400 to 2483.5 megahertz. When one of the two frequencies f 1 and f 2, e . g ., f 2 is cho9en between the two ranges, e.g., about 2200 megahertz, the other frequency, e.g., fl may be chosen between about 300 and 440 megahertz.
The bimodal signal 106 may be coupled to a binary encoder 109, for Pn~ofl;ng a data stream 110. The data stream 110, comprising a sequence of data bits 111, may be coupled to the binary encoder 109, which may generate a first fres~uency, e.g., f~ 107, when a data bit 111 in the data stream 110 is a "0" bit, and may generate a second frequency, e.g., fH 108, when a data bit 111 in the data stream 110 is a " 1 " bit .
The present invention also provides for monitoring a frequency in each band (or transmitting to a frequency in each band) at once, because both (fl + f2) and (fl - f2) can be stepped down to the same i ntP ~ ~ te frequency with a single local oscillator. When the ; nt~-rlnP.l; ~te fres~uency is 260 MHz and the local oscillator is set to 2180 MHz, the present invention allows operation at both , . _ _ _ _ _ _ . , .. .. . . _ _ _ _ _ _ _ _ . _ _ _ _ _ _ Wo 95112925 2 ~ 7 ~ PCT/[~S94~1~4~;1 1920 MHz and 2440 M~Iz. When the local oscillator is eet lo MHz greater, the present invention then allows opera-tion at both 1930 MHz and 2450 MHz, i.e., two frequencies each lD MHz greater. Thus for paired frequencies, the 5 present invention allows reception or transmission on either frequency (or both) in the pair.
Figure 2 shows a ~I.,YL hle frequency generator.
A reference frequency signal 201 may be coupled to a multiplier 2D2. The multiplier 2D2 may generate a signal 10 f (s) 203, which may be coupled to a voltage-controlled oscillator (VCO) 204. The VCO 204 may be coupled to an output node 205, which provides an output frequency signal 206, and may also be coupled in a feedback configuration to the multiplier 202 by way of a ~luyl hle divide-by-N
counter 207. The ~L~JyL hle divide-by-N counter 208 may be programmed by a set of control lines 209.
Al t ernat i~re Emho~; m~nt q While preferred embodiments are disclosed herein, many variations are possible which remain within the concept 20 and scope of the invention, and these variations would become clear to one of ordinary skill in the art after perusal of the specification, drawings and claims herein.
For example, information which is encoded for trans-mission is referred to herein as ~data", but it would be 25 clear to those of ordinary skill in the art, after perusal of this application, that these data could comprise data, voice (encoded digitally or otherwise) error-correcting codes, control information, or other signals, and that this would be within the scope and spirit of the inven-30 tion.
Dual-Mode Wireless Unit With Two S~read-SPectrum Freauençy Bands Backqround of the Invention 1. Pield of the Inventiçn This invention relates to a dual moae wireless unit which uses two spread-spectrum communication bands.
5 2. Descri~tion of Related Art In spread-spectrum modulation in a wireless telephone system, operation in more than one frequency band can be difficult, due to the wide separation between frequency bands. For example, operation in the 900 megahertz and lO laO0 megahertz bands could require a synthesizer capable of covering approximately l, 000 megahertz in frequency spectrum. However, in hand-held equipment such as tele-phones, it is undesirable to use more than one synthesiz-er, or even more than one oscillator, due to increased 15 cost, weight, and related considerations.
Accordingly, it would be advantageous to provide a spread-spectrum system in which a single, relatively narrow, synthesi2er would serve more than one operating f requency band .
20 Summarv of the Invention The invention provides a dual-band spread-spectrum modulator which uses a single, relatively narrow, synthe-sizer to serYe two operating frequency bands. In the lower frequency band, the synthesizer may operate in a 25 high-side injection mode, while in the higher frequency range, the synthesizer may operate in a low-side injection mode. In a preferred embodiment, the lower frequency range may comprise about 1850 to l990 megahertz, while the higher frequency range may comprise about 2400 to 24a3 . 5 3 0 megahertz .
Wo 95/l2925 ~ O C~ PCTIUS94/12464 Brief Descril~tion of the Drawinqs Figure 1 shows a dual-mode spread-spectrum modulator with two frequency bands. s Figure 2 shows a pLU_~' hle frequency generator.
Descri~tion of the Preferred Embodiment Figure 1 shows a dual-mode spread-spectrum modulator with two frequency bands.
A first frequency source 101 may generate a first frequency fl 102, while a second frequency source 103 may generate a second frequency f2 104. The first frequency fl 102 and the second frequency f2 104 may be coupled to a multiplier 105, which may generate a bimodal signal 106 with a frequency distribution over two fres~uency ranges f~
107 and fH 108. In a preferred embodiment, the lower of the two frequencies fL 107 (f~ = fl - f2) may range from about 1850 to l990 megahertz, while the higher of the two frequencies fH 108 ~fH = fl + f2) may range from about 2400 to 2483.5 megahertz. When one of the two frequencies f 1 and f 2, e . g ., f 2 is cho9en between the two ranges, e.g., about 2200 megahertz, the other frequency, e.g., fl may be chosen between about 300 and 440 megahertz.
The bimodal signal 106 may be coupled to a binary encoder 109, for Pn~ofl;ng a data stream 110. The data stream 110, comprising a sequence of data bits 111, may be coupled to the binary encoder 109, which may generate a first fres~uency, e.g., f~ 107, when a data bit 111 in the data stream 110 is a "0" bit, and may generate a second frequency, e.g., fH 108, when a data bit 111 in the data stream 110 is a " 1 " bit .
The present invention also provides for monitoring a frequency in each band (or transmitting to a frequency in each band) at once, because both (fl + f2) and (fl - f2) can be stepped down to the same i ntP ~ ~ te frequency with a single local oscillator. When the ; nt~-rlnP.l; ~te fres~uency is 260 MHz and the local oscillator is set to 2180 MHz, the present invention allows operation at both , . _ _ _ _ _ _ . , .. .. . . _ _ _ _ _ _ _ _ . _ _ _ _ _ _ Wo 95112925 2 ~ 7 ~ PCT/[~S94~1~4~;1 1920 MHz and 2440 M~Iz. When the local oscillator is eet lo MHz greater, the present invention then allows opera-tion at both 1930 MHz and 2450 MHz, i.e., two frequencies each lD MHz greater. Thus for paired frequencies, the 5 present invention allows reception or transmission on either frequency (or both) in the pair.
Figure 2 shows a ~I.,YL hle frequency generator.
A reference frequency signal 201 may be coupled to a multiplier 2D2. The multiplier 2D2 may generate a signal 10 f (s) 203, which may be coupled to a voltage-controlled oscillator (VCO) 204. The VCO 204 may be coupled to an output node 205, which provides an output frequency signal 206, and may also be coupled in a feedback configuration to the multiplier 202 by way of a ~luyl hle divide-by-N
counter 207. The ~L~JyL hle divide-by-N counter 208 may be programmed by a set of control lines 209.
Al t ernat i~re Emho~; m~nt q While preferred embodiments are disclosed herein, many variations are possible which remain within the concept 20 and scope of the invention, and these variations would become clear to one of ordinary skill in the art after perusal of the specification, drawings and claims herein.
For example, information which is encoded for trans-mission is referred to herein as ~data", but it would be 25 clear to those of ordinary skill in the art, after perusal of this application, that these data could comprise data, voice (encoded digitally or otherwise) error-correcting codes, control information, or other signals, and that this would be within the scope and spirit of the inven-30 tion.
Claims (18)
1. A multi-band spread-spectrum communication apparatus comprising a multi-band spread-spectrum modulator comprising:
a dual-band frequency source comprising only one frequency synthesizer, said frequency synthesizer generates a first frequency, said frequency synthesizer having a synthesizer frequency output range, said first frequency falling within said synthesizer frequency output range, a frequency source which generates a second frequency, a multiplier having inputs coupled to said frequency synthesizer and said frequency source, said multiplier having a first and a second output frequency ranges, said first output frequency range defined by a sum of said first frequency and said second frequency, said second output frequency range defined by a difference between said second frequency and said first frequency;
said synthesizer frequency output range is narrower than the range from the lowest frequency of said first or second output frequency range to the highest frequency of said first or second output frequency range; and a binary encoder coupled to said dual-band frequency source.
a dual-band frequency source comprising only one frequency synthesizer, said frequency synthesizer generates a first frequency, said frequency synthesizer having a synthesizer frequency output range, said first frequency falling within said synthesizer frequency output range, a frequency source which generates a second frequency, a multiplier having inputs coupled to said frequency synthesizer and said frequency source, said multiplier having a first and a second output frequency ranges, said first output frequency range defined by a sum of said first frequency and said second frequency, said second output frequency range defined by a difference between said second frequency and said first frequency;
said synthesizer frequency output range is narrower than the range from the lowest frequency of said first or second output frequency range to the highest frequency of said first or second output frequency range; and a binary encoder coupled to said dual-band frequency source.
2. The apparatus of claim 1 wherein said binary encoder comprises a spread-spectrum encoder.
3. The apparatus of claim 1 wherein said first output frequency range spans from 2400 megahertz to 2483.5 megahertz.
4. The apparatus of claim 1 wherein said second output frequency range spans from 1850 megahertz to 1990 megahertz.
5. The apparatus of claim 1 wherein said frequency synthesizer comprises:
a reference frequency signal source;
a programmable divide-by-N counter;
a multiplier having inputs coupled to said programmable divide-by-N counter and said reference frequency signal source; and a voltage-controlled oscillator having an input coupled to said multiplier, said voltage-controlled oscillator having an output coupled to said programmable divide-by-N counter.
a reference frequency signal source;
a programmable divide-by-N counter;
a multiplier having inputs coupled to said programmable divide-by-N counter and said reference frequency signal source; and a voltage-controlled oscillator having an input coupled to said multiplier, said voltage-controlled oscillator having an output coupled to said programmable divide-by-N counter.
6. The apparatus of claim 1 wherein a signal having a frequency in both of said first and second output frequency ranges are transmitted at once.
7. The apparatus of claim 1 further comprising a receiver.
8. The apparatus of claim 7 wherein said receiver comprises a single local oscillator.
9. The apparatus of claim 7 wherein said receiver monitors a frequency in both of said first and second output frequency ranges at once.
10. A method of multi-band spread-spectrum communication comprising the steps of:
generating a first frequency with only one frequency synthesizer;
generating a second frequency;
multiplying said first frequency and said second frequency to generate a signal having a first and a second output frequency ranges, said first output frequency range defined by a sum of said first frequency and said second frequency, said second output frequency range defined by a difference between said second frequency and said first frequency, wherein said frequency synthesizer has a synthesizer frequency output range which is narrower than the range from the lowest frequency of said first or second output frequency range to the highest frequency of said first or second output frequency range; and encoding said signal.
generating a first frequency with only one frequency synthesizer;
generating a second frequency;
multiplying said first frequency and said second frequency to generate a signal having a first and a second output frequency ranges, said first output frequency range defined by a sum of said first frequency and said second frequency, said second output frequency range defined by a difference between said second frequency and said first frequency, wherein said frequency synthesizer has a synthesizer frequency output range which is narrower than the range from the lowest frequency of said first or second output frequency range to the highest frequency of said first or second output frequency range; and encoding said signal.
11. The method of claim 10 wherein said encoding step comprises spread-spectrum encoding.
12. The method of claim 10 wherein said first output frequency range spans from 2400 megahertz to 2483.5 megahertz.
13. The method of claim 10 wherein said second output frequency range spans from 1850 megahertz to 1990 megahertz.
14. The method of claim 10 wherein said step of generating a first frequency comprises the steps of:
generating a reference frequency signal;
generating a signal from a programmable divide-by-N
counter which is coupled to a voltage-controlled oscillator;
multiplying said reference signal and said signal from said programmable divide-by-N counter to generate a multiplied signal; and coupling said multiplied signal to said voltage-controlled oscillator to generate said first frequency.
generating a reference frequency signal;
generating a signal from a programmable divide-by-N
counter which is coupled to a voltage-controlled oscillator;
multiplying said reference signal and said signal from said programmable divide-by-N counter to generate a multiplied signal; and coupling said multiplied signal to said voltage-controlled oscillator to generate said first frequency.
15. The method of claim 10 wherein a signal having a frequency in both of said first and second output frequency ranges are transmitted at once.
16. The method of claim 10 further comprising the step of receiving spread-spectrum signals.
17. The method of 16 wherein said receiving step monitors a frequency in both of said first and second output frequency ranges at once.
18. A spread-spectrum transmitter comprising:
a dual-band frequency source comprising only one frequency synthesizer, said frequency synthesizer generating a first frequency, a frequency source having as an output a second frequency, a multiplier having inputs coupled to said frequency synthesizer and said frequency source, said multiplier having a first and a second output frequency ranges, said first output frequency range defined by a sum of said first frequency and said second frequency, said second output frequency range defined by a difference between said second frequency and said first frequency; and a binary encoder coupled to said dual-band frequency source.
a dual-band frequency source comprising only one frequency synthesizer, said frequency synthesizer generating a first frequency, a frequency source having as an output a second frequency, a multiplier having inputs coupled to said frequency synthesizer and said frequency source, said multiplier having a first and a second output frequency ranges, said first output frequency range defined by a sum of said first frequency and said second frequency, said second output frequency range defined by a difference between said second frequency and said first frequency; and a binary encoder coupled to said dual-band frequency source.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US14649293A | 1993-11-01 | 1993-11-01 | |
| US08/146,492 | 1993-11-01 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2175085A1 true CA2175085A1 (en) | 1995-05-11 |
Family
ID=22517619
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002175085A Abandoned CA2175085A1 (en) | 1993-11-01 | 1994-10-31 | Dual-mode wireless unit with two spread-spectrum frequency bands |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0727112A4 (en) |
| JP (1) | JP3692140B2 (en) |
| KR (1) | KR960706234A (en) |
| CA (1) | CA2175085A1 (en) |
| IL (1) | IL111471A (en) |
| WO (1) | WO1995012925A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IL114924A (en) * | 1994-08-18 | 2000-02-17 | Omnipoint Corp | Multi-land multi-mode communication system |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5537002A (en) * | 1978-08-24 | 1980-03-14 | Fujitsu Ltd | Fs modulation system |
| US4435821A (en) * | 1981-03-24 | 1984-03-06 | Nippon Electric Co., Ltd. | Receiver in a frequency hopping communication system |
| DE3627045A1 (en) * | 1986-08-09 | 1988-05-11 | Quante Fernmeldetechnik Gmbh | Alarm system |
| US4979170A (en) * | 1988-01-19 | 1990-12-18 | Qualcomm, Inc. | Alternating sequential half duplex communication system |
| US5079768A (en) * | 1990-03-23 | 1992-01-07 | Metricom, Inc. | Method for frequency sharing in frequency hopping communications network |
| AU642571B2 (en) * | 1991-01-21 | 1993-10-21 | Sony Corporation | Spread spectrum signal receiving apparatus |
| CA2102914A1 (en) * | 1991-05-13 | 1992-11-26 | Robert C. Dixon | Dual mode transmitter and receiver |
-
1994
- 1994-10-31 KR KR1019960702229A patent/KR960706234A/en not_active Application Discontinuation
- 1994-10-31 EP EP95908412A patent/EP0727112A4/en not_active Withdrawn
- 1994-10-31 CA CA002175085A patent/CA2175085A1/en not_active Abandoned
- 1994-10-31 WO PCT/US1994/012464 patent/WO1995012925A1/en not_active Application Discontinuation
- 1994-10-31 IL IL111471A patent/IL111471A/en not_active IP Right Cessation
- 1994-10-31 JP JP51332595A patent/JP3692140B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| EP0727112A4 (en) | 1998-01-21 |
| JPH09504669A (en) | 1997-05-06 |
| IL111471A (en) | 1998-06-15 |
| IL111471A0 (en) | 1994-12-29 |
| KR960706234A (en) | 1996-11-08 |
| EP0727112A1 (en) | 1996-08-21 |
| WO1995012925A1 (en) | 1995-05-11 |
| JP3692140B2 (en) | 2005-09-07 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued | ||
| FZDE | Discontinued |
Effective date: 20011031 |