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Low Complexity Farrow Differential Channelizer Algorithm

Temidayo Otunniyi, Adedotun O. Owojori, Erastus O. Ogunti, Akinlolu A. Ponnle Published in Algorithms

Communications on Applied Electronics
Year of Publication: 2015
© 2015 by CAE Journal

Temidayo Otunniyi, Adedotun O.owojori, Erastus O Ogunti and Akinlolu A Ponnle. Article: Low Complexity Farrow Differential Channelizer Algorithm. Communications on Applied Electronics 1(6):36-42, April 2015. Published by Foundation of Computer Science, New York, USA. BibTeX

	author = {Temidayo Otunniyi and Adedotun O.owojori and Erastus O. Ogunti and Akinlolu A. Ponnle},
	title = {Article: Low Complexity Farrow Differential Channelizer Algorithm},
	journal = {Communications on Applied Electronics},
	year = {2015},
	volume = {1},
	number = {6},
	pages = {36-42},
	month = {April},
	note = {Published by Foundation of Computer Science, New York, USA}


Reduction in hardware complexities is vital in communication. The major contribution to hardware complexity in many technologies is the multiplier utilized. This work present a proposed algorithm based on Farrow differential polynomial interpolation. This interpolator filter is a time varying poly-phase filter that uses fractional delay to reduce the integer sampling rates to fractional rates. It is a novel polynomial interpolator with less multiplier usage and inherent linear phase low pass filter. The digitized intermediate frequency (IF) by ADC is derived from mixing the signal RF with a local oscillator signal of a given fixed/variable frequency. Digitization using an analog to digital converter (ADC) capable of running at a sampling time of greater or twice the IF with maximum dynamic range of 100 MHz [This is contrary to the direct down conversion of multiband RF to band pass signals where under sampling is used. The algorithm was designed using Altera Digital Signal Processing tool box in MATLAB/ Simulink environment. When implemented it leads to reduction in the computational complexity, power consumption and silicon area. It also showed that a power gain of -15 dBm was observed as output for the GSM channel when compared with the existing modified farrow algorithms which have power gain of -9. 4dBm and farrow polynomial algorithms with power gain of 10. 59dBm. The decimation factor of 260 for a frequency range of 270. 70 kHz was used. Thus a remarkable lower power gain, lower complexity and lower power consumption in mobile system was obtained when compared to farrow polynomial algorithm and modified farrow algorithm.


  1. Rouphael, T. J. (2009). RF and Digital Signal Processing for software Defined Radio. Pp 371-375. Elsevier Inc.
  2. Farrow, C. W. (1988), A Continously Variable Digital Delay Element. 2641-2645. IEEE International Symposium.
  3. Laasko, T. , Valimaki, V. , Karjalainen, M. and Laine, U. (1996). Splitting the Unit Delay. IEEE Signal Processing Magazine. Vol. 13. Pp: 30-60.
  4. Valimaki,V, A new filter implementation strategy for Lagrange interpolation,"Proc. IEEE Int. Symp. Circuits and Systems, pp. 361–364,
  5. Hermanowicz, E. (2004), On designing a wideband fractional delay filter using the Farrow approach," in Proc. EUSIPCO'2004, Austria, Sep. 6–10, pp. 961–964.
  6. Farrow,C. W . (1988), A continuously variable digital delay element," in Proc. IEEE ISCAS'88, Espoo, Finland, 1988, pp. 2641–2645.
  7. Blok, M. (2005), Farrow structure implementation of fractional delay filter optimal in Chebyshev Sense, in Proc. SPIE, vol. 6159, Wilga, Poland, p. 61594.
  8. Harris, F. J. (1997) , Performance and design of Farrow filter used for arbitrary resampling, in Proc. DSP'97, vol. 2, Santorini, Greece, 1997, pp. 595– 599.
  9. Hentschel, T. , Henker M. , and Fettweis G. (1999), The Digital Front- End of Software Radio Terminals, IEEE Personal Communications, pp 6-12.
  10. Ching-Hsiang, T. and Sun-Chung, C. (2006), Direct Down Conversion of Multiband RF Signals using Band Pass
  11. Johansson, . H and Lowenborg, P. (2003), On the design of adjustable fractional delay fir filters. Circuits and Systems II: Analog and Digital Signal Processing, IEEE Transactions on, 50(4):164– 169.
  12. H°akan Johansson. (2011), Farrow-structure-based reconfigurable bandpass linear-phase fir filters for integer sampling rate conversion. Circuits and Systems II: Express Briefs, IEEE Transactions on, 58(1):46–50
  13. Eberspacher,J. ,Vogel, H. ,, Bettstette, C. and Hartman,C. (2009) "GSM-Architecture, Protocols,Services". 3rd Edition. John Willey and Sons. Germany.


Farrow Differential algorithm, Channelization, Multirate Digital Filter Bank, Software Defined Radio, Digital Down Conversion