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Encode 10110001110 with unipolar, polar, bipolar codes

Short answer

Unipolar NRZ: + 0 + + 0 0 0 + + + 0. NRZ-L: + – + + – – – + + + –. NRZ-I (from –V): + + – + + + + – + – –. RZ: +0 –0 +0 +0 –0 –0 –0 +0 +0 +0 -0. Manchester: ↑ ↓ ↑ ↑ ↓ ↓ ↓ ↑ ↑ ↑ ↓. AMI: + 0 – + 0 0 0 – + – 0.

Encode the following bit stream using unipolar (NRZ), polar (NRZ-L, NRZ-I, RZ, Manchester), bipolar (AMI) 10110001110.

Conventions used:

  • Unipolar NRZ: 1 = +V, 0 = 0 V.
  • NRZ-L: 1 = +V, 0 = −V (level depends on the bit value).
  • NRZ-I: a 1 causes a transition at the start of the bit, a 0 keeps the previous level (starting level assumed −V).
  • RZ: 1 = +V for the first half then 0; 0 = −V for the first half then 0 (returns to zero in every bit).
  • Manchester: mid-bit transition; 1 = low-to-high, 0 = high-to-low.
  • Bipolar AMI: 0 = zero; 1s alternate +V and −V, first 1 is +V.
unipolar
   1   0   1   1   0   0   0   1   1   1   0   
+V ────┐   ┌───────┐           ┌───────────┐   
0      └───┘       └───────────┘           └───
-V                                             

NRZ-L
   1   0   1   1   0   0   0   1   1   1   0   
+V ────┐   ┌───────┐           ┌───────────┐   
0      │   │       │           │           │   
-V     └───┘       └───────────┘           └───

NRZ-I
   1   0   1   1   0   0   0   1   1   1   0   
+V ────────┐   ┌───────────────┐   ┌───┐       
0          │   │               │   │   │       
-V         └───┘               └───┘   └───────

RZ
   1   0   1   1   0   0   0   1   1   1   0   
+V ──┐     ┌─┐ ┌─┐             ┌─┐ ┌─┐ ┌─┐     
0    └─┐ ┌─┘ └─┘ └─┐ ┌─┐ ┌─┐ ┌─┘ └─┘ └─┘ └─┐ ┌─
-V     └─┘         └─┘ └─┘ └─┘             └─┘ 

Manchester
   1   0   1   1   0   0   0   1   1   1   0   
+V   ┌───┐   ┌─┐ ┌───┐ ┌─┐ ┌─┐   ┌─┐ ┌─┐ ┌───┐ 
0    │   │   │ │ │   │ │ │ │ │   │ │ │ │ │   │ 
-V ──┘   └───┘ └─┘   └─┘ └─┘ └───┘ └─┘ └─┘   └─

AMI
   1   0   1   1   0   0   0   1   1   1   0   
+V ────┐       ┌───┐               ┌───┐       
0      └───┐   │   └───────────┐   │   │   ┌───
-V         └───┘               └───┘   └───┘   

Level sequences (per bit):

  • Unipolar NRZ: +, 0, +, +, 0, 0, 0, +, +, +, 0
  • NRZ-L: +, −, +, +, −, −, −, +, +, +, −
  • NRZ-I: + (toggled from −), +, −, +, +, +, +, −, +, −, −
  • RZ: +0, −0, +0, +0, −0, −0, −0, +0, +0, +0, −0
  • Manchester: ↑, ↓, ↑, ↑, ↓, ↓, ↓, ↑, ↑, ↑, ↓
  • AMI: +, 0, −, +, 0, 0, 0, −, +, −, 0

The long run of three 0s (bits 5 to 7) gives a flat line in unipolar, NRZ-L (at −V), NRZ-I and AMI, which is a synchronization problem. RZ and Manchester still have transitions in every bit.

✓ Answer checked by Claude Sonnet 5.5

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