Methods and apparatus for common scrambling for rank adaptation
Aspects of the present disclosure include methods, apparatuses, and computer readable media for identifying an initial rank, modulating information into a first plurality of layers associated with the initial rank, scrambling the first plurality of layers by a first common scrambler to generate a first plurality of scrambled layers, transmitting, to the receiver, the first plurality of scrambled layers, receiving an indication of failed demodulation of a portion of the first plurality of scrambled layers, modulating at least a portion of the information into a second plurality of layers, wherein the second plurality of layers includes a same number of layers as the first plurality of layers, scrambling the second plurality of layers by a second common scrambler to generate a second plurality of scrambled layers, and transmitting, to the receiver, the second plurality of scrambled layers.
1 . A method of wireless communication by a transmitter in a network, comprising:
identifying an initial rank;
modulating information into a first plurality of layers associated with the initial rank;
scrambling the first plurality of layers by a first common scrambler to generate a first plurality of scrambled layers;
transmitting, to a receiver, the first plurality of scrambled layers;
receiving an indication of failed demodulation of a portion of the first plurality of scrambled layers;
modulating at least a portion of the information into a second plurality of layers, wherein the second plurality of layers includes a same number of layers as the first plurality of layers;
scrambling the second plurality of layers by a second common scrambler to generate a second plurality of scrambled layers; and
transmitting, to the receiver, the second plurality of scrambled layers.
2 . The method of claim 1 , wherein:
the first common scrambler is different from the second common scrambler.
3 . The method of claim 1 , wherein:
scrambling the first plurality of layers further comprises scrambling the first plurality of layers by a first plurality of scramblers to generate the first plurality of scrambled layers, wherein the first plurality of scramblers are different per layer; and
scrambling the second plurality of layers further comprises scrambling the second plurality of layers by a second plurality of scramblers to generate the second plurality of scrambled layers, wherein the second plurality of scramblers are different per layer.
4 . The method of claim 3 , wherein:
the first plurality of scramblers and the second plurality of scramblers are identical.
5 . The method of claim 1 , wherein:
at least one of the first common scrambler or the second common scrambler are cell specific or user specific.
6 . The method of claim 1 , wherein:
at least a portion of the first plurality of layers overlaps with at least a portion of the second plurality of layers.
7 . A transmitter, comprising:
a memory comprising instructions;
a transceiver; and
one or more processors operatively coupled with the memory and the transceiver, the one or more processors configured to execute instructions in the memory to:
identify an initial rank;
modulate information into a first plurality of layers associated with the initial rank;
scramble the first plurality of layers by a first common scrambler to generate a first plurality of scrambled layers;
transmit, to a receiver, the first plurality of scrambled layers;
receive an indication of failed demodulation of a portion of the first plurality of scrambled layers;
modulate at least a portion of the information into a second plurality of layers, wherein the second plurality of layers includes a same number of layers as the first plurality of layers;
scramble the second plurality of layers by a second common scrambler to generate a second plurality of scrambled layers; and
transmit, to the receiver, the second plurality of scrambled layers.
8 . The transmitter of claim 7 , wherein:
the first common scrambler is different from the second common scrambler.
9 . The transmitter of claim 7 , wherein:
scrambling the first plurality of layers further comprises scrambling the first plurality of layers by a first plurality of scramblers to generate the first plurality of scrambled layers, wherein the first plurality of scramblers are different per layer; and
scrambling the second plurality of layers further comprises scrambling the second plurality of layers by a second plurality of scramblers to generate the second plurality of scrambled layers, wherein the second plurality of scramblers are different per layer.
10 . The transmitter of claim 9 , wherein:
the first plurality of scramblers and the second plurality of scramblers are identical.
11 . The transmitter of claim 7 , wherein:
at least one of the first common scrambler or the second common scrambler are cell specific or user specific.
12 . The transmitter of claim 7 , wherein:
at least a portion of the first plurality of layers overlaps with at least a portion of the second plurality of layers.
13 . A non-transitory computer readable medium having instructions stored therein that, when executed by one or more processors of a transmitter, cause the one or more processors to:
identify an initial rank;
modulate information into a first plurality of layers associated with the initial rank;
scramble the first plurality of layers by a first common scrambler to generate a first plurality of scrambled layers;
transmit, to a receiver, the first plurality of scrambled layers;
receive an indication of failed demodulation of a portion of the first plurality of scrambled layers;
modulate at least a portion of the information into a second plurality of layers, wherein the second plurality of layers includes a same number of layers as the first plurality of layers;
scramble the second plurality of layers by a second common scrambler to generate a second plurality of scrambled layers; and
transmit, to the receiver, the second plurality of scrambled layers.
14 . The non-transitory computer readable medium of claim 13 , wherein:
the first common scrambler is different from the second common scrambler.
15 . The non-transitory computer readable medium of claim 13 , wherein:
scrambling the first plurality of layers further comprises scrambling the first plurality of layers by a first plurality of scramblers to generate the first plurality of scrambled layers, wherein the first plurality of scramblers are different per layer; and
scrambling the second plurality of layers further comprises scrambling the second plurality of layers by a second plurality of scramblers to generate the second plurality of scrambled layers, wherein the second plurality of scramblers are different per layer.
16 . The non-transitory computer readable medium of claim 15 , wherein:
the first plurality of scramblers and the second plurality of scramblers are identical.
17 . The non-transitory computer readable medium of claim 13 , wherein:
at least one of the first common scrambler or the second common scrambler are cell specific or user specific.
18 . The non-transitory computer readable medium of claim 13 , wherein:
at least a portion of the first plurality of layers overlaps with at least a portion of the second plurality of layers.
19 . A transmitter, comprising:
means for identifying an initial rank;
means for modulating information into a first plurality of layers associated with the initial rank;
means for scrambling the first plurality of layers by a first common scrambler to generate a first plurality of scrambled layers;
means for transmitting, to a receiver, the first plurality of scrambled layers;
means for receiving an indication of failed demodulation of a portion of the first plurality of scrambled layers;
means for modulating at least a portion of the information into a second plurality of layers, wherein the second plurality of layers includes a same number of layers as the first plurality of layers;
means for scrambling the second plurality of layers by a second common scrambler to generate a second plurality of scrambled layers; and
means for transmitting, to the receiver, the second plurality of scrambled layers.
20 . The transmitter of claim 19 , wherein:
the first common scrambler is different from the second common scrambler.
21 . The transmitter of claim 19 , wherein:
the means for scrambling the first plurality of layers further comprises scrambling the first plurality of layers by a first plurality of scramblers to generate the first plurality of scrambled layers, wherein the first plurality of scramblers are different per layer; and
the means for scrambling the second plurality of layers further comprises scrambling the second plurality of layers by a second plurality of scramblers to generate the second plurality of scrambled layers, wherein the second plurality of scramblers are different per layer.
22 . The transmitter of claim 21 , wherein:
the first plurality of scramblers and the second plurality of scramblers are identical.
23 . The transmitter of claim 19 , wherein:
at least one of the first common scrambler or the second common scrambler are cell specific or user specific.
24 . The transmitter of claim 19 , wherein:
at least a portion of the first plurality of layers overlaps with at least a portion of the second plurality of layers.