IEC TR 63675-1:2026

IEC TR 63675-1 ®
Edition 1.0 2026-02
TECHNICAL
REPORT
Transmitting and receiving equipment for radiocommunication - Transciever
technologies and their performance standards -
Part 1: Low phase-noise oscillator technologies using photonics techniques

ICS 33.060.20  ISBN 978-2-8327-1044-9

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CONTENTS
FOREWORD . 2
INTRODUCTION . 4
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and abbreviated terms . 5
3.1 Terms and definitions . 5
3.2 Abbreviated terms. 5
4 General description of phase noise and its requirements . 6
4.1 Causes of phase noise properties in an oscillator . 6
4.2 Phase noise in radiocommunication services . 7
4.3 Requirement of phase noise parameters in advanced radiocommunication
services . 8
5 Principle of oscillators using photonics technologies . 9
5.1 Optoelectronic oscillator . 10
5.1.1 Principle and configuration . 10
5.1.2 Example results of the OEO . 10
5.2 Micro-ring resonator for optical frequency comb generation. 12
5.2.1 Principle and configuration . 12
5.2.2 Example results of the micro-ring comb generator . 13
Bibliography . 15

Figure 1 – Schematic illustration of the power spectrum of the SSB phase noise of the
oscillator. 6
Figure 2 – Symbol expression in IQ phasor plane and constellation diagrams of QPSK
(4-ary QAM), 16-ary QAM, and 64-ary QAM . 7
Figure 3 – Amplitude and phase noise deviations of the symbol in IQ plane . 8
Figure 4 – Schematic of the envelop of the modulated signal and the oscillator carrier
signal in the single carrier modulation case and the OFDM case . 8
Figure 5 – Typical block diagram of radiocommunication transceiver . 9
Figure 6 – Schematic block diagram of optoelectronic oscillator . 10
Figure 7 – Block diagram of injection-locked 94-GHz OEO system . 11
Figure 8 – SSB phase noise spectra of injected signal and resultant OEO signal at
94,5 GHz [6] . 11
Figure 9 – SSB phase noise at 10 kHz of the generated signal at different values of
oscillation power to injection power ratio . 12
Figure 10 – Schematic illustration of optical spectrum of optical frequency comb . 13
Figure 11 – Schematic drawing of experimental setup for Kerr micro-ring resonator
soliton OFC . 13
Figure 12 – Basic performance of 560 GHz spacing Kerr micro-ring-resonator
soliton OFC . 13
Figure 13 – Schematic drawing of experimental setup for generation of THz wave . 14
Figure 14 – SSB phase noise PSD of f generated by photomixing of the stabilized
THz
OFC [8] . 14

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Transmitting and receiving equipment for radiocommunication -
Transceiver technologies and their performance standards -
Part 1: Low phase-noise oscillator technologies
using photonics techniques
FOREWORD
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shall not be held responsible for identifying any or all such patent rights.
IEC TR 63675-1 has been prepared by IEC technical committee 103: Transmitting and receiving
equipment for radiocommunication. It is a Technical Report.
The text of this Technical Report is based on the following documents:
Draft Report on voting
103/285/DTR 103/288/RVDTR
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this Technical Report is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts of the IEC 63675 series, published under the general title Transmitting and
receiving equipment for radiocommunication - Transceiver technologies and their performance
standards, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
INTRODUCTION
A frequency-stabilized oscillator is an indispensable device in radiocommunication due to the
radio regulations and reduction of the computing resources for frequency offset compensation
in the demodulation process. In principle, the combination of crystal oscillators and multipliers
has been used for the generation of the microwave signal in conventional microwave bands, as
well as lower millimetre-wave frequency bands less than 40 GHz. Raising the carrier frequency
of radiocommunication is necessary to increase the wireless transmission capacity. In this
scenario, the multiplication factor also increases and finally, the phase noise of the signal is
degraded. An intrinsic phase noise degradation by the multiplication is expressed by 20 log m,
where m is a multiplication factor. For the realization of the advanced modulation formats such
as an orthogonal frequency division multiplexing with a multilevel modulation, a low-phase noise
oscillator is necessary.
An optoelectronic oscillation technique is a promising solution for achieving both high oscillation
frequency and low phase noise, as the optical transmission technique, thanks to the broadband
nature of optical signals, makes it possible to obtain a long cavity with a high quality factor. In
this document, the principle of the optoelectronic oscillation and an example of the usage for
the radiocommunications are shown as a guideline to the experts and engineers, who design
and develop the radiocommunication transceivers in high frequency millimetre-wave systems
and terahertz-wave systems.
1 Scope
Millimetre wave and terahertz wave radio communication services require low phase noise
oscillators in order to comply with radio regulations and reduce the computing resources
required for demodulation processes. This document provides the principle and application of
the optoelectronic oscillation technologies using the photonics technique as a guideline for the
design of the radiocommunication transceivers.
2 Normative references
There are no normative references in this document.
3 Terms, definitions and abbreviated terms
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
3.1 Terms and definitions
3.1.1
optoelectronic oscillator
oscillator that provides an electronic signal using circuits composed of an optical cavity and
electrical inputs, outputs, and converters
3.1.2
Kerr effect
electro-optic effect in which an applied electric field makes an optically isotropic substance
birefringent, the difference of refractive indexes being proportional to the square of the
magnitude of the electric field strength
3.2 Abbreviated terms
BPF band-pass filter
EDFA erbium-doped fibre amplifier
FM frequency modulation
FSR free Spectral Range
LD laser diode
LTE long-term evolution
MZM Mach-Zehnder-interferometer-type optical modulator
OEO optoelectronic oscillator
OFDM orthogonal frequency division multiplexing
OFDMA orthogonal frequency division multiple access
PD photodiode
PRBS pseudo random bit stream
PM phase modulation
QAM quadrature amplitude modulation
QPSK quadrature phase-shift keying
SSB single side band
UTC-PD uni-traveling carrier photodiode
4 General description of phase noise and its requirements
4.1 Causes of phase noise properties in an oscillator
Phase noise of an oscillator is a key parameter to generate high-precision signals in advanced
radiocommunication services such as high-capacity wireless communications and high-
precision radars.
4 3 2
The phase noise generally consists of five parts: 1/f , 1/f , 1/f , 1/f, and frequency-independent
components shown in Figure 1. 1/f component is caused by the random walk frequency-
modulated (FM) noise: mechanical vibration, environmental temperature, etc. This effect will
) is mainly generated by the design
randomly shift the carrier frequency. Flicker FM noise (1/f
of the active oscillator components including the selection of the components and organization
of the order of the components. The
...