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    antenna size frequency

    Can any body help to know the relation between antenna size and frequency?

    appreciate if can support by equations.

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    antenna size wavelength

    Refer to any antenna book which contains materials about microstrip antenna.



    •   Alt12th April 2009, 15:05

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    antenna size and frequency

    Hello engmnour,
    In general antenna size decreases with increase in frequency. For accurate dimensions refer to the text books.

    Regards



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    antenna size vs frequency

    antenna length and frequences are Inversely proportional



    •   Alt15th April 2009, 08:29

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    relation between antenna length and wavelength

    Accoring to b.p. lathi's MODERN DIGITAL AND ANALOGUE COMMUNICATION SYSTEMS, third edition

    page number 11
    line number 3-4

    "for efficient radiation of electromagnetic energy the radiating antenna should be of the order of one-tneth or more the wavelength of signal radiated"

    and according to frequecny- wavelength relationship...
    we know

    Frequency * wavelength = speed of light

    frequency = (speed of light)/ (wavelength)

    so as u increase ur frequency, ur wavelength decreases causing the product of both equals to speed of light (constant). and as wavelength decreases, its corresponding size of antenna also decreases, ultimately the result comes out to be,
    INCREASE IN FREQUENCY CAUSES SIZE OF ANTENNA TO DECREASE.

    hope u can understand
    regards
    mosfets.bjt


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    antenna size and wavelength

    as frequency increases size of the antenna decreases...generally size= λ/10 where λ is the wavelength



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    Re: what is relation between antenna size and frequency?

    Hello Mr. mosfets.bjt,

    How are you, Hope you are doing great. well your answer really attracted me as i was looking for an answer that " Why cant we use 0.3m dish for 11 GHz frequency? " Your definition and equation gave the exact answer i was looking for, but i am now little confused that why cant we use above 0.6m dish for 38 GHz frequency and above.. i mean as you said, ""for efficient radiation of electromagnetic energy the radiating antenna should be of the order of one-tneth or more the wavelength of signal radiated" and in case of 38 GHz if we use 1.2m antenna, it would likely be more than multiple 10 times of the radiated signal, then why cant we??????


    Best regards,
    Masood.



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    Re: what is relation between antenna size and frequency?

    hello friend;
    as other friends told u if the frequncy increases the wave lengh decreases. and since your antena must at least be 1/10 of the wave lengh, antena size get smaller.but still u can use longer antenas than needed and have good quality.that is why we make the antena longer to get better quality of voice in AM radio.( it is carried by lower frenquncy carriers than FM) .even once I used the door way instead of antena and the radio had a great quality!:D



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    Re: antenna size and wavelength

    Quote Originally Posted by rfndmw
    as frequency increases size of the antenna decreases...generally size= λ/10 where λ is the wavelength
    But what about circular microstrip patch antenna? How to decide it's dimentions? I am interested in ground plane size.



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