  Generators of spacetime translations and Lorentz group transformations form
the Lie algebra of the Poincar\'e group and give rise to the Casimir invariants
for a specification of elementary particle characteristics. Moreover quantum
operators of coordinate and momentum components of a particle in Minkowski
spacetime together with Lorentz group generators belong to the known
noncommutative algebra. This algebra can be generalized under some constraints,
in particular, the Lorentz invariance condition. The generalized algebra
depends on the new fundamental constants with dimensions of length (L), mass
(M) and action (H). Quantum fields, which can be constructed with the help of
representations of this algebra, are referred to as HLM generalized quantum
fields and the associated particles as HLM quantum particles. Relations between
spacetime observables of a HLM quantum particle depend on the new constants and
lead to complication of the Poincar\'e invariant equations for canonical
fields. The modification of a quantum measurement procedure is needed in order
to take into account inherent features of HLM quantum particles.
