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β: This English translation is in beta — the Traditional-Chinese original is the authoritative version.

Paper Summary Table

The source folder contains 5 PDFs. This page lays them out in a single table, then organizes their division of labor from a teaching viewpoint: which paper is the ISF core, which extends to rings, which covers injection, which is actually off-topic, and which equations are the same thing written differently, plus which notation differs and needs to be unified.

Honesty note (up front): of these 5, 4 are Hajimiri-series oscillator phase-noise/ injection papers, and 1 (Hajimiri_ISCS_98.pdf = [P5]) is actually a cross-coupled sense-amplifier paper, unrelated to ISF — this site treats it only as a footnote. Also, the frequently co-mentioned PPV / adjoint / PSS / PNoise / Floquet topics have no dedicated paper among these 5 PDFs — they belong to external literature and are honestly flagged below.

One-page summary table

Data comes from extracted/paper_metadata.json. Citation strings follow the site convention verbatim (see references).

PaperYearMain ContributionKey EquationsKey FiguresWhat We Use It For
[P1] Hajimiri & Lee, A General Theory of Phase Noise in Electrical Oscillators, IEEE JSSC 33(2):179–194 (general.pdf, paper_001)1998Establishes the LTV / ISF theory of oscillator noise: introduces Γ(ω0τ)\Gamma(\omega_0\tau) and the qmaxq_{max} normalization, derives closed forms for 1/f21/f^2 and 1/f31/f^3 plus design rules (large qmaxq_{max}, small Γrms\Gamma_{rms}, waveform symmetry to suppress c0c_0).Eq.(1) output decomposition; (9) ΔV=Δq/C\Delta V=\Delta q/C; (10)(11) ISF impulse response and convolution; (12) Fourier series; (19)(20) summation and Parseval; (21) the signature 1/f21/f^2 formula; (22)(23)(24) flicker 1/f31/f^3 and cornerFig. 4 (peak vs ZC injection), Fig. 6 (Δϕ\Delta\phiΔq\Delta q linearity), Fig. 7 (LC/ring ISF shapes), Fig. 8 (nω0n\omega_0→carrier downconversion), Fig. 11/12 (1/f3,1/f21/f^3,1/f^2,floor panorama and corner)The ISF core foundation — the theory source of chapters 02/03 and most labs.
[P2] Hajimiri, Limotyrakis & Lee, Jitter and Phase Noise in Ring Oscillators, IEEE JSSC 34(6):790–804 (jitter_ring.pdf, paper_002)1999Applies the ISF to ring oscillators: closed forms for jitter/phase noise, the ΓrmsN3/2\Gamma_{rms}\propto N^{-3/2} scaling, "ring phase noise nearly independent of stage count NN at fixed power and frequency", and how rise/fall symmetry suppresses 1/f1/f upconversion.(8) accumulated jitter σΔt=κΔt\sigma_{\Delta t}=\kappa\sqrt{\Delta t}; (11)(12) κ2Γrms2/qmax2in2/Δf\kappa^2\propto\Gamma_{rms}^2/q_{max}^2\cdot\overline{i_n^2}/\Delta f; (15) f0=1/(2NτD)f_0=1/(2N\tau_D); (16) Γrms=2π2/(3η3)1/N1.5N3/2\Gamma_{rms}=\sqrt{2\pi^2/(3\eta^3)}\cdot1/N^{1.5}\propto N^{-3/2}; text result L1/f283ηVDDVcharkTP(ω0/Δω)2\mathcal{L}\vert _{1/f^2}\approx\frac{8}{3\eta}\,\frac{V_{DD}}{V_{char}}\,\frac{kT}{P}(\omega_0/\Delta\omega)^2 (η\eta is the stage-delay proportionality constant of Eq.14, 1\approx 1; γ\gamma enters only through Vchar=ΔV/γV_{char}=\Delta V/\gamma)Fig. 5 (ring single-stage ISF), Fig. 8 (Γrms\Gamma_{rms} vs NN; solid line is 4/N1.54/N^{1.5}@η=0.75\eta=0.75), Fig. 17 (phase noise vs symmetry control voltage, minimum at the symmetric point)The ring-oscillator extension — chapter 06 lc_vs_ring, symmetry, and lab_03.
[P3] B. Hong & A. Hajimiri, Injection Locking and Pulling…Part I: Time-Synchronous Modeling and Injection Waveform Design, IEEE JSSC 54(8):2109–2121 (BHongGenTheor-I_JSSC2019_Postprint.pdf, paper_003)2019Builds a time-synchronous injection locking/pulling model on the ISF, generalizing Adler 1946 to arbitrary oscillators and arbitrary injection waveforms: a single first-order (generalized Adler) equation predicts lock range, locked phase, and mode stability.classic Adler ϕ˙=ωLsinϕ+Δωinj\dot\phi=-\omega_L\sin\phi+\Delta\omega_{inj}; generalized Adler (time-averaged) θ˙=ω0ωinj1qmaxΓ(ωinjt+θ)iinj\dot\theta=\omega_0-\omega_{inj}-\frac{1}{q_{max}}\langle\Gamma(\omega_{inj}t+\theta)\,i_{inj}\rangle = Eq.(30) (this site's Γ\Gamma uses the sign convention opposite to [P3], hence the - before the averaged term; numerically equivalent, the original PDF Eq.(30) has ++); sinusoidal lock range ωL=12IinjΓ~1\omega_L=\tfrac{1}{2}I_{inj}\vert\tilde\Gamma_1\vert = Eq.(35), p.2114 (verified)Fig. 1–3 (time-synchronous injection model and ISF formulation)Advanced injection-locking deep dive (chapter 05, elective); demonstrates the same Γ\Gamma extending beyond phase noise.
[P4] B. Hong & A. Hajimiri, …Part II: Amplitude Modulation in LC Oscillators, Transient Behavior, and Frequency Division, IEEE JSSC 54(8):2122–2139 (BHongGenTheor-II_JSSC2019_Postprint.pdf, paper_004)2019Introduces the APF (amplitude perturbation function) — the amplitude analogue of the ISF (units A1\mathrm{A^{-1}}): handles amplitude modulation under injection, transient locking, and injection-locked frequency division. In an ideal LC the ISF and APF are orthogonal.APF definition Δ(ϕ):=0D(τ,ϕ)dτ\Delta(\phi):=\int_0^\infty D(\tau,\phi)\,d\tau (units A1\mathrm{A^{-1}}) = Eq.(19), p.2126 (decomposition D=Λ~(ϕ)d(τ,ϕ)D=\tilde\Lambda(\phi)\,d(\tau,\phi) = Eq.(18); ideal-LC orthogonality = Eq.(26), p.2128, verified)Fig. 5, p.2126 (effect of instantaneous charge injection on the oscillator: ISF / excess phase / amplitude decay / APF; ISF and APF orthogonal in an ideal LC)APF / advanced deep dive (chapter 05, elective); chapter 02's phase_vs_amplitude_noise borrows it to explain "why amplitude noise decays".
[P5] A. Hajimiri & R. Heald, Design Issues in Cross-Coupled Inverter Sense Amplifier, Proc. IEEE ISCAS 1998 (Hajimiri_ISCS_98.pdf, paper_005)1998Analytic design of the cross-coupled-inverter sense amplifier (regeneration speed, mismatch offset, FOM). Completely unrelated to ISF/phase noise; included only because it was in the source folder with the same author.None (off-topic, equations not transcribed) TODO: equations not transcribed because off-topicNoneFootnote — honestly explains the mislabeling; the only conceptual link is the cross-coupled-pair regeneration/positive-feedback mechanism shared with latches/LC oscillation.

⚠️ = manual_verification_needed = true, exact constants/forms still need comparison against the original PDFs. See claims_cross_reference and equation_index for details.


Teaching viewpoint: who teaches what

Which paper is the ISF core foundation

[P1] is the foundation of the whole site. Every LTV/ISF concept — Γ(ω0τ)\Gamma(\omega_0\tau), the qmaxq_{max} normalization, the convolutional phase response, Fourier downconversion, the 1/f21/f^2/1/f31/f^3 closed forms — all comes from here. Chapters 02 (foundations) and 03 (isf core theory) map almost section-by-section to [P1] Secs. III–IV, and lab_01/02/04/05/06/07 all reproduce figures and equations from [P1].

Which paper extends to rings

[P2] grounds [P1]'s general theory in the ring oscillator: the same Γrms2/qmax2\Gamma_{rms}^2/q_{max}^2 logic yields accumulated jitter (claim C6), ΓrmsN3/2\Gamma_{rms}\propto N^{-3/2} (claim C8), and "ring phase noise nearly independent of NN at fixed power/frequency" (claim C7). Chapter 06's lc_vs_ring, symmetry and lab_03 use it.

Which paper covers adjoint / PPV / PSS / PNoise / simulation

Honestly: none of these 5 papers is dedicated to PPV/adjoint/PSS/PNoise.

  • PPV (perturbation projection vector) / adjoint method / Floquet theory is the rigorous mathematical foundation behind the ISF, but it comes from the broader literature (e.g. Demir–Mehrotra–Roychowdhury 2000, Kaertner), not among the 5 downloaded PDFs. This site treats them as standard external literature, explicitly flagged in effective_isf (claim C13).
  • PSS (periodic steady-state) / PNoise are numerical methods in commercial simulators (e.g. SpectreRF) for extracting ISF/ phase noise, and likewise are not the subject of any of these 5 papers; this site cites them only conceptually and does not claim they come from the downloaded PDFs.
  • The closest thing to "simulation" is actually [P1]'s own limitation that "real circuits require transient impulse response or adjoint/PSS methods to extract the ISF" — i.e., simulation extraction is mentioned, but has no dedicated paper. All labs on this site are teaching toy models (not transistor-level), reproducing the concepts in Python, not a real PSS/PNoise flow.

Which paper corrects / critiques / extends prior work

[P1] supersedes Leeson's empirical formula. Leeson 1966's L\mathcal{L} expression (with 2FkT/Ps2FkT/P_s, (ω0/2QΔω)2(\omega_0/2Q\Delta\omega)^2, 1+ω1/f3/Δω1+\omega_{1/f^3}/|\Delta\omega|) is an empirical fit: it can draw the 1/f31/f^3, 1/f21/f^2, floor regions, but FF (noise factor) and the 1/f31/f^3 corner are after-the-fact fitting parameters, not computed from first principles. [P1]'s contribution is precisely to compute these three regions from first principles with the ISF, and to point out that the 1/f31/f^3 corner is not the device's 1/f1/f corner, but ω1/f(c0/c1)2\omega_{1/f}(c_0/c_1)^2 ([P1] Eq.(24), claim C5) — a key correction to the Leeson empirical model. The Leeson formula itself is not one of the 5 downloaded PDFs; this site uses it only for comparison (see equation_index row 19, flagged reference ⚠️).

In addition, [P3] extends/generalizes Adler 1946's injection-locking equation, and [P4] supplies the amplitude dimension (APF) missing from [P1]/[P3]. Neither Adler's nor Leeson's original paper is among these 5 PDFs.

Which equations are the same thing written differently across papers

Concept[P1] formOther papers' formUnifying note
phase sensitivityΓ(ω0τ)\Gamma(\omega_0\tau) (ISF)[P2] keeps Γ\Gamma; [P3] writes Γ(θ+ϕ)\Gamma(\theta+\phi) inside the injection inner productthe same Γ\Gamma; [P3] just uses it as the injection weighting kernel
phase evolutionϕ(t)=1qmaxΓindτ\phi(t)=\frac{1}{q_{max}}\int\Gamma i_n\,d\tau (Eq.11, noise view)[P3] ϕ˙=Δω1qmaxΓiinj\dot\phi=\Delta\omega-\frac{1}{q_{max}}\langle\Gamma i_{inj}\rangle (injection view)the same LTV phase equation, one driven by random noise, one by deterministic injection
1/f21/f^2 phase noiseEq.(21) Γrms2/qmax2\propto\Gamma_{rms}^2/q_{max}^2[P2] κ2Γrms2/qmax2\kappa^2\propto\Gamma_{rms}^2/q_{max}^2 (jitter version)the same Γrms2/qmax2\Gamma_{rms}^2/q_{max}^2 ratio; phase noise and accumulated jitter are the same physics (claims C3=C6 share the source)
the two directions of sensitivityphase version Γ\Gamma only[P4] adds the amplitude version, APF Λ\LambdaΓ\Gamma (tangential/phase) and Λ\Lambda (radial/amplitude) are two orthogonal projections on the limit cycle

Which notation differs and needs unifying

Different papers use different symbols for the same quantity; this site always follows notation:

  • Offset frequency: [P1] mostly uses Δω\Delta\omega (rad/s), datasheets/SerDes use Δf\Delta f (Hz); this site uses both, Δω=2πΔf\Delta\omega=2\pi\Delta f.
  • The ISF's DC: note that c0c_0 is a Fourier coefficient, while the ISF's DC value is c0/2c_0/2 (Eq.(12)) — very easy to get wrong when computing the 1/f31/f^3 corner (Eq.(24)); this site repeats the reminder.
  • Amplitude sensitivity: [P4]'s APF is written Λ(ϕ)\Lambda(\phi) with units A1\mathrm{A^{-1}}; it has different dimensions from the dimensionless ISF Γ\Gamma and must not be mixed up.
  • PPV/adjoint/Floquet: this site does not use their dedicated notation (e.g. Demir's v1T(t)v_1^T(t)) in the main track, mentioning them only as external literature in effective_isf.

For the full symbol comparison (including a "per-paper notation / remarks" column) see the "per-paper notation comparison" section of notation.

Key takeaways

  • [P1] = ISF core; [P2] = ring extension; [P3]/[P4] = injection locking / APF advanced; [P5] = sense amplifier, unrelated to ISF (honestly flagged).
  • None of the papers is a dedicated PPV/adjoint/PSS/PNoise paper; those belong to external literature (e.g. Demir 2000).
  • [P1] supersedes the Leeson empirical formula from first principles, and corrects "1/f31/f^3 corner ≠ device 1/f1/f corner".
  • Across papers, Γ\Gamma, the phase equation, and Γrms2/qmax2\Gamma_{rms}^2/q_{max}^2 are often the same thing seen from different angles; notation is always unified per notation.

Further reading