IEEE Circuits and Systems Magazine - Q3 2019 - 30

Table I.
Performance of proposed MCS.
M

Rc

C woCR

C wCR

EVM

EVM wIPT

BER woCR

BER wCR

BER woCRwIPT

BER wCRwIPT

BPSK

0.50

57.6 kbit/s

28.8 kbit/s

1.96%

1.82%

0

0

0

0

QPSK

0.50

115 kbit/s

57.6 kbit/s

2.27%

2.14%

0

0

0

0

QPSK

0.75

115 kbit/s

86.4 kbit/s

2.12%

2.18%

0

0

0

0

16-QAM

0.50

230 kbit/s

115 kbit/s

2.15%

2.12%

0

0

0

0

16-QAM

0.75

230 kbit/s

173 kbit/s

1.86%

2.06%

0

0

0

0

64-QAM

0.67

346 kbit/s

259 kbit/s

1.86%

2.08%

0

0

0

0

64-QAM

0.75

346 kbit/s

259 kbit/s

2.01%

1.81%

0

0

0

0

64-QAM

0.83

346 kbit/s

288 kbit/s

2.13%

1.90%

0

0

0

0

256-QAM

0.75

461 kbit/s

346 kbit/s

1.74%

1.70%

2.00 $ 10-06

0

2.10 $ 10-05

0

1.73%

-05

0

-06

0

-03

0

-03

3.34 $ 10-03

256-QAM
1024-QAM
1024-QAM

0.83
0.75
0.83

461 kbit/s
576 kbit/s
576 kbit/s

384 kbit/s
432 kbit/s
480 kbit/s

1.91%
1.76%

1.68%

1.80%

1.79%

input voltage and power as well as the output power for
the single IPT system and with connected communication electronic comprising an active data transmission.
These results show, that there is nearly no change in
the efficiency but a small increase of the in- and output

28
Voltage (V), Power (W)

Voltage (V), Power (W)

28
26
24
22
20
18
16
14

0

0.5

1 1.5
t (µs)
(a)

Input Voltage

2

26
24
22
20
18
16
14

0

Input Power

0.5

1 1.5
t (µs)
(b)

2

Output Power

Figure 14. Measurement of the power transfer (a) without
and (b) with communication.

Table II.
Comparison of the IPT system with and without
connected communication circuit.
Uin

Pin

Uout

Pout

26.0 V 22.5 W 24.7 V 20.4 W 90.4%

Sim. all

26.0 V 23.0 W 24.9 V 20.7 W 90.2%

Meas. only IPT 25.9 V 23.4 W 24.4 V 20.1 W 86.0%

30

25.9 V 23.7 W 24.7 V 20.4 W 86.1%

IEEE CIRCUITS AND SYSTEMS MAGAZINE

1.78 $ 10

-03

2.45 $ 10

-03

1.73 $ 10

6.98 $ 10
-05

3.49 $ 10

-03

1.72 $ 10
2.71 $ 10

power. For comparability of the measurement the communication system is powered separately and not included in the efficiency. All values are shown in Table II.
On the other side, the communication performance
should not be distorted by IPT. Due to the frequency
multiplexing approach, simultaneous IPT only marginally increases the noise floor of the received data signal.
This is underlined by the measured SNR at the receiver.
Without IPT it is 32.4 dB and is reduced to 30.63 dB for
simultaneous transmission of 20 W. As some spurious
signals are convolved into the transmission band, the
SNR is further decreased and results in a spurious free
dynamic range (SFDR) of 25.11 dB (compare to Fig. 13).
As described in section IV the frequency selective
attenuation of the channel changes when the IPT is active. Fig. 15 depicts the normalized frequency spectrum
of the received baseband signal. It can be seen that with
active IPT, the slope of the attenuation increases. Thus,
OFDM with its robustness against the fading channel is
the perfect transmission mode.
This is verified by Table  I. Both, EVM and BER
with or without active IPT do not distinctly deviate.
For maximized through put the transmission rate can
be even further increased to 461 kbit/s with a BER of
smaller than 10 -5. It is therefore proven that the transmission performance is very tolerant against external
or internal interference.

h

Sim. only IPT

Meas. all

2.99 $ 10

B. Comparison to the State of the Art
For a comparison of this system to the state of the art
Table III lists all relevant system parameters, the power
delivery, the carrier frequency of the power and data
communication as well as the data rate. It can be seen
THIRD QUARTER 2019
IEEE Circuits and Systems Magazine - Q3 2019

Table of Contents for the Digital Edition of IEEE Circuits and Systems Magazine - Q3 2019
