---

Data transmission rate and frequency

---

• Data (transmission) rate
  • Fact:

    Computer communication often use digital signalling (I.e., computers transmit a series of pulses that represent bits)

    ---

  • Definition: data rate

    data rate (or data transmission rate) = number of bits transmitted in one second Unit is: bits/sec

    Example:

  ---

  ---

  ---

  ---

  ---

  ---

• Data rate and frequency
  • Observable fact:

    Faster data rate will result in a signal with a higher frequency

    Example:

    The frequency of the second signal is higher (more cycles per second)

  ---

  ---

  ---

  ---

• Relationship between bandwidth and data transmission rate

  • Clearly:

    A higher data (transmission) rate wil result in a signal with higher frequencies

    ---

    ---

  • Limitation:

    When the frequency of the transmitted signal is too high: The signal become unrecognizable due to attentuation !!!