**2. Multiband impulse radio**

The idea of the MIR-UWB architecture is based on [45, 46]. The architecture proposed there comprises a transmitter using multiple bands and impulse radio within the bands to transmit data and a receiver, which detects only the energy of the transmitted impulses. The combination of energy detection receiver and multiband enables a flexible high data rate system with low power consumption.

Bandplan

BP1 |·|<sup>2</sup> *Ti*

BP2 |·|<sup>2</sup> *Ti*

BP*<sup>N</sup>* |·|<sup>2</sup> *Ti*

Synchronisation

accompanied by a very simple receiver design [36, 38, 54]. The performance measure is based on the average symbol error probability (SEP) or bit error probability (BEP) and will

In the additive white gaussian noise (AWGN) channel the received signal *R* is the sum of the transmitted signal *s* and white Gaussian noise *W* with the power spectral density of *N*0/2:

The transmitted signal *s* is a weighted pulse *p*. The amplitude of the pulse is *am*. Thus, the

<sup>2</sup>(*t*) d*t* = *a*<sup>2</sup>

where *si* := *s*(*i*/(2*B*)) and *pi* := *p*(*i*/(2*B*)) and *B* denoting the bandwidth. The received energy can be approximated by a finite sum of 2*D* = 2*TiB* samples [56]. The event {*A* = *am*} with the range A = {*a*0, ... , *aM*−1} describes a transmitted symbol with the amplitude *am*. Without loss of generality the integration starts at *t*<sup>0</sup> = 0. In order to measure the energy, the detector squares the received signal *R*(*t*) and integrates the result over the time interval *Ti*.

> *Ti* 0

*m*

 *t*0+*Ti t*0

<sup>0</sup> ADC

MIRA – Physical Layer Optimisation for the Multiband Impulse Radio UWB Architecture 3

<sup>0</sup> ADC

Multiplexer

<sup>0</sup> ADC

Channelestimation

*R*(*t*) = *s*(*t*) + *W*(*t*) = *am p*(*t*) + *W*(*t*). (1)

*p*2(*t*) d*t*

*R*2(*t*) d*t*. (2)

binary data

LNA

**Figure 2.** MIR-UWB receiver

**3.1. Demodulation**

be derived in the following section.

energy of a transmitted signal is:

*ES* =

= 2*D* ∑ *i*=1

 *t*0+*Ti t*0

*s*

*si* = *a*<sup>2</sup> *m* 2*D* ∑ *i*=1 *pi*,

The received energy, normalized by the power spectral density *N*0/2, is:

*<sup>Y</sup>* <sup>=</sup> <sup>2</sup> *N*0
