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Re: any rf expert here
If the receiver front end is designed to receive 2.4 GHz, the the transmitter carrier frequency better be 2.4GHz. Whether you get to 2.4GHz via an IF or direct modulation is a design trade off. Having an IF requires more parts, e.g., mixer, filters, etc., but the LO...
Re: filter [hlp]
That's 103% BW BPF. You may have to pay a lot of money for this design if you need any level or rejection from this filter? You might consider a highpass-lowpass combo, perhaps inserting an op-amp in between if necessary.
Hilbert transform can be used to generate digital IQ modulation, and if used in combination with DDS and a high speed DAC, one can generate an IF directly out of the DAC without a mixer. Digital IQ provides minimal I-Q imbalance and DC offset, thus minimizes image level and LO leakage at IF...
look up table gmsk
You are mostly correct. There are different ways to generate a GMSK waveform and an LUT is certainly one of them. The main idea is to filter the bits with a gaussian filter, and spread the phase transition of that filtered bit over the 1/(B*T) symbols (Gaussian filter...
gmsk mod
The DAC on the modulator side brings the digital information into analog domain for transmission, and the ADC on the demodulator side brings the analog signal into digital domain for decoding. The modulation and demodulation process is a whole lot more complicated then just these two...
Re: any rf expert here
Not sure there is any way around reading up on the subject; perhaps you would consider dropping one of the other classes? Good luck!
Re: Matching LNA-mixer
lambda=c/f only applies in free space, e.g. waveguide circuits. When the signal propagation is done over a substrate (or PWB), the guided wave length, λg is used in stead. For example, in microstrip configuration, λg=c/f/sqrt(ε_eff)
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