US007532676B2

(12) Ulllted States Patent (10) Patent N0.: US 7,532,676 B2 Fonseka et al. (45) Date of Patent: May 12, 2009

(54) SINGLE SIDEBAND AND QUADRATURE 2008/0072126 A1 * 3/2008 Norris et al. .............. .. 714/792

MULTIPLEXED CONTINUOUS PHASE MODULATION OTHER PUBLICATIONS

Kahn and Thomas, “Bandwidth Properties and Optimum Demodu (75) Inventors; J ()hn P, Fonseka, Plano, TX (US); Eric lation of Single Sideband FM,” IEEE Transactions on Communica

Morgan Bowling’ San Jose (CR) tions Technology, vol. COM-14, No. 2, Apr. 1966, pp. 113-117. Chadwick, “Binary Single-Sideband Phase-Modulated Systems,”

(73) Assigneez Trellis Phase Communications, LP, IEEE Transactions on Information Theory, Jan. 1972, pp. 214-215. Marshall TX (Us) Anderson et al., “A BandWldth-Ef?clent Class of Signal Space

’ Codes,” IEEE Transactions on Information Theory, vol. IT-24, No. 6, . _ . . . . Nov. 1978, pp. 703-712.

( * ) Nonce' SubJeCt. to any (gsglalmeé’. the germdofthls PiZZi et al., “Convolutional Coding Combined With Continuous Patent 15 exten e or a Juste un er 35 Phase Modulation,” IEEE Transactions on Communications, vol. U-S-C- 154(1)) by 540 days- COM-33, N0. 1,1311. 1985, pp. 20-29.

(21) A 1 N 11/253 730 Rimoldi, “A Decomposition Approach to CPM,” IEEE Transactions PP - OJ 9 on Information Theory, vol. 34, No. 2, Mar. 1988, pp. 260-270.

(22) Filed: 0a. 20, 2005 (Continued)

_ _ _ Primary ExamineriKhai Tran

(65) Pnor Pubhcatlon Data (74) Attorney, Agent, or FirmiEric M. DoWling US 2007/0092018 A1 Apr. 26, 2007

(57) ABSTRACT 51 Int. Cl.

( ) H04L 23/02 (200601) A class of bandwidth reduction techniques are used develop a H04L 27/28 (200601) broad class of modulation types collectively called S'SB-FM.

(52) us. Cl. ..................................... .. 375/265; 375/260 These slgnals Fan be use? ‘0 Comm,“ Commumcanon 5Y5‘ . . . tems that prov1de bandW1dth-normal1Zed performance ga1ns

(58) Field of Classi?cation Search ............... .. 375/256, . of 10 dB or more When compared to popular pr1or art modu

375/259, 272, 298, 320, 322, 329, 346, 265, . . . . . 375/260 370/208 4 01 476 lat1on methods. An aspect of the 1nvent1on 1nvolves mapping

See a lication ?le for Com lete gearch hist’o ’ trell1s paths 1n a complex slgnal space onto correspondlng pp p ry' real-valued trellis signals With desirable spectral properties.

(56) References Cited The invention can be used map continuous phase modulated

U.S. PATENT DOCUMENTS (CPM) signals onto simpler amplitude-modulated trellis sig nals having double the channel capacity of prior art CPM signals. Multi-amplitude signaling and frequency division

4,835,791 A 5/1989 Daoud _ _ _

5,852,476 A 12/1998 Limberg multlplexlng may also be lncorporated to further accommo 6,667,760 B1 12/2003 Limberg date more information per symbol. 6,947,509 B1 9/2005 Wong

2002/0094043 A1* 7/2002 Chu et al. ................. .. 375/346 22 Claims, 26 Drawing Sheets

600 605 610

I / / 630 j x I k BASEBAND ‘( )‘ COMPLEX a REAL "11(1)

—> TRELLIS TRANSFORM > MODULATION

V S t 645/ Q) POST-P (—)> A

615 620 \670 650 j j 642

x f _ Jk BASEBAND 2( ) COMPLEX _) REAL m,(t 7') —> TRELLIS TRANSFORM V

MODULATION

640

US 7,532,676 B2 Page 2

OTHER PUBLICATIONS

Fonseka et al., “Combined Coded Multi-h CPFSK Signaling,” IEEE Transactions on Communications, vol. 38, No. 10, Oct. 1990, pp. 1708-1715. Abriskamar et a1 ., “Suboptimum Detection of Trellis Coded CPM for Transmission on Bandwidth- and Power-Limited Channels,” IEEE Transactions on Communications, vol. 39, No. 7, Jul. 1991, pp. 1065-1074. Sasase et al., “Multi-h Phase-Coded Modulation,” IEEE Communi cations Magazine, Dec. 1991, pp. 46-56. HohuboWicZ et al.,, “Good Multi-T Phase Codes Under Bandwidth and Complexity Constraints,” IEEE Transactions on Information Theory, vol. 40, No. 5, Sep. 1994, pp. 1699-1702. Fonseka et al., “Nonlinear Continuous Phase Frequency Shift Key ing,” IEEE Transactions on Communications, vol. 39, No. 10, Oct. 1991, pp. 1473-1481. Sundberg, “Continuous Phase Modulation,” IEEE Communications Magazine, Apr. 1986, pp. 25-37. Premji et al., “A Practical Receiver Structure for Multi-h CPM Sig nals,” IEEE Transactions on Communications, vol. 35, No. 9, Sep. 1987, pp. 901-908. Nyirenda and Korn “Acutocorrelation Function and Power Spectral Density of Complex Phase Modulated Signals Derived from Full Response CPM,” IEEE Transactions on Communications, vol. 38, No. 10, Oct. 1990, pp. 1649-1652.

Ginesi et al., “Symbol and Superbaud Timing Recovery in Multi-H Continuous Phase Modulation,” IEEE Transactions on Communica tions, vol. 47, No. 5, May 1999, pp. 664-667. Mujtaba, “A Novel Scheme for Transmitting QPSK as a Single Sideband Signal,” IEEE, 1998, pp. 592-597. Campenalla et al., “Optimum Bandwidth-Distance Performance in Partial Response CPM Systems,” IEEE Transactions on Communi cations, vol. 44, No. 2, Feb. 1996, pp. 148-151. Aulin et al., “Continuous Phase ModulationiPart I: Full Response Signaling,” IEEE Transactions on Communications, vol. COM-29, No. 3, Mar. 1981, pp. 196-209. Aulin et al., “Continuous Phase ModulationiPart II: Partial Response Signaling,” IEEE Transactions on Communications, vol. COM-29, No. 3, Mar. 1981, pp. 210-225. Tassduq et al., “OFDM-CPM Signals for Wireless Communica tions,” Canadian Journal ofElect. Comput. Eng, vol. 28, No. 1, Jan. 2003, pp. 19-25. Tassduq et al., “Performance of Optimum and Suboptimum OFDM CPM Receivers over Multipath Fading Channels,” Wireless Commu nications and Mobile Computing, vol. 5, 2005, pp. 365-374. Tassduq et al., “PAPR Reduction of OFDM signals using Multiamplitude CPM,” Electronic Letters, Aug 2002, pp. 915-917. Tassduq et al., “OFDM-CPM Signals,” Electronic Letters, Jan. 2002, vol. 38, No. 2, pp. 80-81.

* cited by examiner

US. Patent May 12, 2009 Sheet 1 0f 26 US 7,532,676 B2

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US. Patent May 12, 2009 Sheet 2 0f 26 US 7,532,676 B2

AQLVWEAQLE IMO-00mm $ 24.55

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2 Emma: mwN_._<:ow A?

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US. Patent May 12, 2009 Sheet 3 0f 26 US 7,532,676 B2

US. Patent May 12, 2009 Sheet 4 0f 26 US 7,532,676 B2

US. Patent May 12, 2009 Sheet 5 0f 26 US 7,532,676 B2

500 COMPUTE /595

CORRELATIONs ‘PM/C)

510 I \ COMPUTE BRANCH

METRICS Bulk)

I \ FOR EACH STATE,

DETERMINE SURVIVING PATH

I 520 FOR EACH STATE, \- DISCARD LOWER

PROBABILTY PATHS

525 I \ UPDATE PATH DATA

STRUCTURES

530 I \ UPDATE PATH

METRICS

515

535 \ I MAKE DELAYED DECISIONS

FIG. 5

US. Patent May 12, 2009 Sheet 8 0f 26 US 7,532,676 B2

800

y {Ti} 2

NONLINEAR D. 1 c P a). OPTIMIZATION 4, —— 0 e

_{"’_‘}, ALGORITHM T 5 Q0 OTHER

PARAMETERS / / ——>I

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TRELLIS ENCODER 805 PATH CONSTRAINTS --—-_—+

US. Patent May 12, 2009 Sheet 9 0f 26 US 7,532,676 B2

1 vvvvvv mm )

\(‘f wxmzox m1 (t) + r m2(t)

FIG. 9

US. Patent May 12, 2009 Sheet 10 0f 26 US 7,532,676 B2

1 l I ‘F l I

<1 stating in ending

dun'ng 1 - _

0.5 - -

C 0 ,_ _.

cm

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US. Patent May 12, 2009 Sheet 11 0f 26 US 7,532,676 B2

b. m1 (t) + m2(t-T/2)

why‘ A

1'1 FIG. 11

US. Patent May 12, 2009 Sheet 12 0f 26 US 7,532,676 B2

signal constellation of c0s(a|p1(t)-pii4)+ c0s(a|p2(t)-pi!4-T!2) 2 1 I l I l I

= = 5'13’ <1 stating ‘ 1:? ending

9 O during .a.

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US. Patent May 12, 2009 Sheet 15 0f 26 US 7,532,676 B2

on: I]

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US. Patent May 12, 2009 Sheet 16 6f 26 US 7,532,676 B2

GENERATE 905 COMPLEX-VALUED / CONSTELLATION

900 V

91O¥ MAP TO REAL CONSTELLATION

I 915 OBTAIN STATE V SEPARATION IN

RV-TRELLIS

I ADD REDUNDANT

ggg/ CONSTELLATION POINTS TO RV-TRELLIS

I 925 DESIGN STATE \ TRANSITIONS TO

KEEP MINIMUM DISTANCE HIGH

930 l \ USE ALL POINTS IN

RV-TRELLIS CONSISTENTLY

I 935 x MAP RV-TRELLIS TO

A SIGNALING SCHEME

FIG. 16

U S. Patent May 12, 2009 Sheet 17 0f 26 US 7,532,676 B2

2.5

FIG. 17