1. The Zigbee Standard (Local copy)
2. Zigbee PHY specs(postscript file)

A. A. Abidi, "RF CMOS comes of age," IEEE Journal of Solid-State Circuits, vol. 39, pp. 549 - 561, April 2004. This paper discusses the development of integrated CMOS radios over the last decade. More than as a technical reference, it is a good overview and contains a list of key references for different stages of the radio.

1. A Classic Tutorial Paper on MSK:IEEE Communication Magazine Paper

1. A Wide-band CMOS LNA Exploiting Thermal Noise Canceling:IEEE JSSC Paper

1. Lee and Messerchmitt, Digital Communication, Chapters 16 and 17

1. H. Darabi, S. Khorram, B. Ibrahim, M. Rofougaran, and A. Rofougaran, "An IF FSK demodulator for bluetooth in 0.35 µm CMOS," 2001 IEEE Custom Integrated Circuits Conference, May 2001.
2. J. Park, E. Joe, M-J. Choe, and B-S. Song, “A 5-MHz IF Digital FM Demodulator,” IEEE J. of Solid-State Circuits, vol. 34, no.1, pp. 3-11, 1999.
3. Tai-Cheng Lee; Chin-Chi Chen, "A mixed-signal GFSK demodulator for Bluetooth" IEEE Transactions on Circuits and Systems II: Express Briefs, Volume 53, Issue 3, March 2006 Page(s):197 - 201.
4. Dehaese, N.; Bourdel, S.; Barthelemy, H.; Bas, G., "Simple demodulator for 802.15.4 low-cost receivers" Radio and Wireless Symposium, 2006 IEEE 17-19 Jan. 2006 Page(s):315 - 318
5. Kwon, H.M.; Kwang Bok Lee, "A novel digital FM receiver for mobile and personal communications", IEEE Transactions on Communications, Volume 44, Issue 11, Nov. 1996 Page(s):1466 - 1476

1. Low power amplifier Y. H. Chee, J. Rabaey, A.M. Niknejad, "A class A/B low power amplifier for wireless sensor networks", Proceedings of the 2004 International Symposium on Circuits and Systems, 2004. ISCAS '04, Volume 4, 23-26 May 2004 Page(s):IV - 409-12 Vol.4

1. Class E Amplifier Nathan O. Sokal and Alan D. Sokal, "Class E - A New Class of High-Efficiency Tuned Single-Ended Switching Power Amplifiers", IEEE Journal of Solid-State Circuits, VOL. SC-10, No. 3, June 1975
2. Extension of Sokal's work Frederick H. Raab, "Idealized Operation of the Class E Tuned Power Amplifier", IEEE Transactions on Circuits and Systems, VOL. CAS-24, No. 12, December 1977
3. Generalised Design Equations for Class-E amplifiers with finite DC feed inductance Mustafa Acar, Anne Johan Annema and Bram Nauta, "Generalized Design Equations for Class-E Power Amplifiers with Finite DC Feed Inductance", 36th European Microwave Conference, 2006
4. A 5-part series on RF Power amplifiers and Transmitter Technologies, by various authors, published in High Frequency Electronics Frederick H. Raab, Peter Asbeck, Steve Cripps, Peter B. Kenington, Zoya B. Popovic, Nick Pothecary, John F. Sevic, and Nathan O. Sokal, "RF and Microwave Power Amplifier and Transmitter Technologies", May 2003 - January 2004
5. A condensed version of the above 5-part series Frederick H. Raab, Peter Asbeck, Steve Cripps, Peter B. Kenington, Zoya B. Popovic, Nick Pothecary, John F. Sevic, and Nathan O. Sokal, "Power Amplifiers and Transmitters for RF and Microwave", Invited Paper, IEEE Transactions on Microwave Theory and Techniques, VOL. 50, No. 3, March 2002

1. The Bible Keith R. Carver and James W. Mink, "Microstrip Antenna Technology", IEEE Transactions on Antennas and Propagation, vol 29, issue 1, Jan 1981, p 2-24
2. Bandwidth improvement using impedance-matching http://ieeexplore.ieee.org/iel4/8/1669/00043553.pdf?tp=&arnumber=43553&isnumber=1669
3. Gap-coupled compact antenna http://ieeexplore.ieee.org/iel5/11208/36089/01711430.pdf?tp=&arnumber=1711430&isnumber=36089
4. Double U-slot antenna H.M. Chen and Y.F. Lin, "Experimental and simulation studies of the probe-fed double U-slot rectangular microstrip antenna", Microwave Conference, 2001. APMC 2001. 2001 Asia-Pacific, vol 2, Dec 2001, p 914-917
5. Jia-Yi Sze and Kin-Lu Wong, "Slotted rectangular microstrip antenna for bandwidth enhancement", IEEE Transactions on Antennas and Propagation, vol 48, issue 8, Aug 2000, p 1149-1152
6. Slotted antenna for bandwidth improvement Jia-Yi Sze and Kin-Lu Wong, "Broadband rectangular microstrip antenna with pair of toothbrush-shaped slots", Electronics Letters, vol 34, issue 23, Nov. 1998, p 2186-2187
7. E-shape antenna suited for thick air substrates F. Yang, Xue-Xia Zhang, Ye Xiaoning and Y. Rahmat-Samii, "Wide-band E-shaped patch antennas for wireless communications", IEEE Transactions on Antennas and Propagation, vol 49, issue 7, July 2001, p 1094-1100

1. Ilku Nam et al., "A 2.4-GHz Low-Power Low-IF Receiver and Direct-Conversion Transmitter in 0.18-um CMOS for IEEE 802.15.4 WPAN Applications" IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 55, NO. 4, APRIL 2007
2. Nam-Jin Oh et al., "Derivation of specs for a 2.4-GHz radio transceiver using IEEE 802.15.4," Circuits and Devices Magazine, IEEE, Volume: 21, Issue: 6, Jan.-Feb. 2006.
3. KLUGE et al., "A FULLY INTEGRATED 2.4-GHz IEEE 802.15.4-COMPLIANT TRANSCEIVER FOR ZigBee APPLICATIONS", IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 41, NO. 12, DECEMBER 2006. (ISSCC paper, ISSCC slides)
4. Cook B. W. et al., {{:mtech2006:04014606.pdf|“An Ultra-Low Power 2.4GHz RF Transceiver for Wireless Sensor Networks in 0.13/spl mu/m CMOS with 400mV Supply and an Integrated