High-frequency generator
The high-frequency generator addresses the issue of large size and high power consumption in conventional systems by employing a tunable laser and optical components to split and delay light waves, enabling efficient high-frequency signal generation.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- NIPPON TELEGRAPH & TELEPHONE CORP
- Filing Date
- 2023-03-30
- Publication Date
- 2026-05-20
AI Technical Summary
Conventional high-frequency signal generation technologies require multiple laser devices and optical components, leading to increased equipment size and power consumption.
A high-frequency generator utilizing a tunable laser, optical splitter, optical delayer, optical multiplexer, and photomixer to generate high-frequency electrical signals with reduced equipment size and power consumption by splitting and delaying light waves at set time intervals.
Generates high-frequency electrical signals efficiently while minimizing equipment size and power consumption through the use of a tunable laser and optical components.
Smart Images
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Abstract
Description
Technical Field
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[0005]
[0001] The present invention relates to a high-frequency generator. <0000 [Patent Document 2] Japanese Patent Publication No. 2009-004858 [Overview of the project] [Problems that the invention aims to solve]
[0006] The technology described in Patent Document 1 performs photomixing using two laser beams. The laser beams are generated by a laser device. Since one light wave is emitted from one laser device, conventionally, two laser devices are used in photomixing that uses two light waves. The technology described in Patent Document 2 shows an example in which two light waves are extracted from an optical frequency comb generated from one laser using a wavelength-selective filter.
[0007] However, the technology described in Patent Document 1 required two laser devices, resulting in a larger equipment size and a doubling of power consumption. On the other hand, the technology described in Patent Document 2 required an optical modulator and an optical filter in addition to the laser device, also resulting in a larger equipment size and higher power consumption. Thus, conventional technologies have the problem of large equipment size and high power consumption when generating high-frequency electrical signals using photomixers.
[0008] This invention was made to solve the above-mentioned problems, and aims to enable the generation of high-frequency electrical signals using a photomixer while suppressing increases in equipment size and power consumption. [Means for solving the problem]
[0009] The high-frequency generator according to the present invention comprises a signal generator that outputs a first voltage and a second voltage different from the first voltage at set time intervals; a tunable laser that emits a first light wave and a second light wave having a different wavelength from the first light wave based on the first and second voltages output from the signal generator; an optical splitter that splits the light wave output from the tunable laser; an optical delayer that delays one of the light waves split by the optical splitter by time; an optical multiplexer that combines the other light wave split by the optical splitter and the light wave delayed by the optical delayer; and a photomixer that converts the combined light from the optical multiplexer into electromagnetic waves. [Effects of the Invention]
[0010] As described above, according to the present invention, the first and second light waves emitted from a tunable laser at set time intervals are split by an optical splitter, and after a set time delay is applied to one of the branch paths, they are combined. This makes it possible to generate high-frequency electrical signals using a photomixer while suppressing increases in equipment size and power consumption. [Brief explanation of the drawing]
[0011] [Figure 1] Figure 1 is a configuration diagram showing the configuration of a high-frequency generator according to an embodiment of the present invention. [Figure 2] Figure 2 is an explanatory diagram illustrating the operation of a high-frequency generator according to an embodiment of the present invention. [Modes for carrying out the invention]
[0012] Hereinafter, a high-frequency generator according to an embodiment of the present invention will be described with reference to Figure 1. This high-frequency generator comprises a signal generator 101, a tunable laser 102, an optical splitter 103, an optical delayer 104, an optical multiplexer 105, and a photomixer 106.
[0013] The signal generator 101 outputs a first voltage and a second voltage different from the first voltage at set time intervals. The signal generator 101 can be composed of, for example, a pulse pattern generator, a power amplifier, and a bias tee.
[0014] The tunable laser 102 emits a first light wave and a second light wave with a different wavelength from the first light wave, based on the first and second voltages output from the signal generator 101. The tunable laser 102 can be, for example, a reflection-type transversal filter (RTF) laser. RTF lasers have the characteristic of being able to switch wavelengths at high speed because their wavelength can be controlled by voltage.
[0015] For example, in the signal generator 101, a predetermined bit pattern (repeating pattern) of 600 Mbit / s is generated by a pulse pattern generator, this bit pattern is amplified by a power amplifier, a bias voltage (negative DC bias) is added by a bias tee, and then applied to the tunable laser 102 (RTF laser). Different voltages (first voltage, second voltage) are output when the bit is "1" and when the bit is "0". By applying these voltages based on bit patterns, the tunable laser 102 can generate (emit) a first light wave with an optical frequency f1 = 193.96 THz when the bit is "1", and generate a second light wave with an optical frequency f2 = 193.70 THz when the bit is "0".
[0016] The optical splitter 103 splits the light wave output from the tunable laser 102. The optical splitter 103 splits the input light wave into a first optical path 121 and a second optical path 122. The optical splitter 103 splits the first and second light waves output from the tunable laser 102 at set time intervals.
[0017] The optical delay device 104 delays one of the optical waves branched by the optical splitter 103 for the time described above. The delay time is the time interval between the output of the first voltage and the output of the second voltage. For example, the optical delay device 104 is installed in the second optical path 122 and delays the optical waves branched into the second optical path 122 for the time described above. The optical delay device 104 delays one of the first optical waves and one of the second optical waves branched by the optical splitter 103 for the time described above.
[0018] For example, the first optical path 121 and the second optical path 122 can be made of optical fibers, and by making the length of the optical fiber of the second optical path 122 longer than that of the optical fiber of the first optical path 121, the extended portion can be used as an optical delay device 104. For example, if T is the time interval between the first and second light waves alternately emitted from the tunable laser 102 by applying the first and second voltages of the bit pattern described above, c is the speed of light, and n is the effective refractive index of the optical fiber, then the optical fiber of the second optical path 122 can be made longer by ΔL to satisfy "ΔL = cT / n". The light wave traveling through the second optical path 122, which has been extended by ΔL, is delayed by time T.
[0019] The optical multiplexer 105 combines the other optical wave branched by the optical splitter 103 with the first optical wave delayed by the optical delayer 104. The optical multiplexer 105 combines the other half of the second optical wave branched by the optical splitter 103 with one half of the first optical wave delayed by the optical delayer 104, and combines the other half of the first optical wave branched by the optical splitter 103 with one half of the second optical wave delayed by the optical delayer 104. Combined waves The resulting light wave travels through the third optical path 123 and is input to the photomixer 106. The photomixer 106 converts the combined light, which has been combined by the optical multiplexer 105, into photoelectric waves to generate electromagnetic waves.
[0020] As described above, the first and second optical waves emitted from the tunable laser 102 to which the first and second voltages are applied at set time intervals, and then branched into the first optical path 121 by the optical splitter 103, pass through the first optical path 121 at set time intervals and are input to the optical multiplexer 105, as shown by the solid line in Figure 2(a).
[0021] For example, during the time from time t0 to time t1 after a set time, the first optical path 121 is passed through by the first light wave, and during the time from time t1 to time t2 after a set time, the second light wave is passed through. Also, during the time from time t2 to time t3 after a set time, the first light wave is passed through the first optical path 121, and during the time from time t3 to time t4 after a set time, the second light wave is passed through. Further, during the time from time t4 to time t5 after a set time, the first light wave is passed through the first optical path 121.
[0022] On the other hand, the first light wave and the second light wave branched to the second optical path 122 by the optical splitter 103 are delayed by the optical delay device 104, and thus, as shown by the dotted line in (b) of FIG. 2, they travel through the second optical path 122 at a set time interval and are input to the optical multiplexer 105.
[0023] For example, during the time from time t1 to time t2 after a set time, the first light wave is passed through the second optical path 122, and during the time from time t2 to time t3 after a set time, the second light wave is passed through. Also, during the time from time t3 to time t4 after a set time, the first light wave is passed through the second optical path 122, and during the time from time t4 to time t5 after a set time, the second light wave is passed through.
[0024] As described above, the first light wave and the second light wave that have passed through the first optical path 121 and the second optical path and are multiplexed by the optical multiplexer 105 travel through the third optical path 123 at a set time interval and are input to the photomixer 106, as shown in (c) of FIG. 2.
[0025] For example, the third optical path 123 passes through the first light wave, shown by the solid line, between time t1, which is a set time after time t0. Also, the third optical path 123 passes through the combined wave of the second light wave, shown by the solid line, and the first light wave, shown by the dotted line, between time t2, which is a set time after time t2, and the combined wave of the first light wave, shown by the solid line, and the second light wave, shown by the dotted line, between time t3, which is a set time after time t4, and the combined wave of the first light wave, shown by the solid line, and the second light wave, shown by the dotted line, between time t4, which is a set time after time t5,
[0026] As described above, in the optical multiplexer 105, the first light wave and the second light wave are combined and output at set time intervals. As a result, the photomixer 106 receives the combined signal of the first light wave and the second light wave at set time intervals. For example, if the tunable laser 102 alternately emits a first light wave of 193.0 THz and a second light wave of 193.3 THz every 100 ps of set time, and the delay amount of the optical delayer 104 is 100 ps, then the optical frequency difference is always 0.3 T Two Hz light waves are introduced into the photomixer 106, and a constant 300 GHz high-frequency signal is generated.
[0027] As described above, according to the present invention, the first and second light waves emitted from a tunable laser at set time intervals are split by an optical splitter, and after a set time delay is applied to one of the branch paths, they are combined. This makes it possible to generate high-frequency electrical signals using a photomixer while suppressing increases in equipment size and power consumption.
[0028] It should be noted that the present invention is not limited to the embodiments described above, and it is clear that many modifications and combinations can be implemented within the technical concept of the present invention by those with ordinary skill in the art. [Explanation of Symbols]
[0029] 101...Signal generator, 102...Tunable laser, 103...Optical splitter, 104...Optical delayer, 105...Optical multiplexer, 106...Photomixer, 121...First optical path, 122...Second optical path, 123...Third optical path.
Claims
1. A signal generator that outputs a first voltage and a second voltage different from the first voltage at set time intervals, A tunable laser that emits a first light wave and a second light wave having a different wavelength from the first light wave based on the first voltage and the second voltage output from the signal generator, An optical splitter that splits the light wave output from the aforementioned tunable laser, An optical delay device that delays one of the light waves branched by the optical splitter by the aforementioned optical splitter for the aforementioned time, An optical multiplexer that combines the other optical wave branched by the optical splitter and the other optical wave delayed by the optical delayer, A photomixer generates electromagnetic waves by converting the combined light from the aforementioned photomultiplexer into photoelectric energy. A high-frequency generator equipped with the following features.
2. In the high-frequency generator according to claim 1, The optical splitter splits the first and second light waves output from the tunable laser, The optical delay device delays one of the first optical waves and one of the second optical waves, which have been branched by the optical splitter, by the aforementioned time. The optical multiplexer combines the other half of the second optical wave branched by the optical splitter with one half of the first optical wave delayed by the optical delayer, and combines the other half of the first optical wave branched by the optical splitter with one half of the second optical wave delayed by the optical delayer. High-frequency generator.