about FSK data question....

super

Dear all :
              In fsk close loop direct Frequency modulation ,
          1.  data rate is higher than loop BW  or lower than loop BW ?
          2.  And what's the relation between data rate and Loop BW ?

4 g$ p' k& `7 ?           Because modulation from VCO , it's a high pass function for VCO vs PLL.
           If modulation frequency > BW , it will be supress by VCO vs PLL transfer function.
* d4 o" t( W6 k8 M! j) C6 l           It will be trace and fix it.  So modulation function is fail.
             Is this concept is right ?
- N' a* @3 c6 W* |( r3 [: {3 p$ [: G                  
                    Thanks .

simenkid

1.data rate可以高於loop bandwidth, 也不可以.端看用什麼architecture
, Y" z$ k6 g" @- O& m2.假使單純在multi-modulus或是由reference端做調制, data-rate高於loop bandwidth則勢必產生失真
4 l( a. f5 J2 S: Y. `
$ z9 F4 x8 Z+ ?: D0 m* D# Z. u直接由PLL Synthesizer調制提升FSK, FM, GMSK等固定波包調制之data rate
可選擇如pre-emphasis或two-point modulation(同時兼顧inband與outband,理論上無頻寬限制)的方式